ATcT [1 , 2 ] enthalpies of formation based on version 1.202 of the Thermochemical Network [3 ]
Below is a list of 0 K and 298.15 K enthalpies of formation
for all 3384 species included in version 1.202 (as of 09/01/2024). This version of ATcT results[3 ] was generated by additional expansion of version 1.176 in order to include species related to the thermochemistry of glycine[4 ].
The elements in their standard states are listed first; the listing order of the other species follows the actual order from the ATcT solution file,
which roughly reflects the number of thermochemically-relevant determinations that include the species in question (highest first).
The intent is to convey a very approximate indication of the robustness of the listed values, which is generally higher toward the top of the list
and lower toward the bottom.
For species other than elements in their standard states, the Species Name acts as a link to the page
itemizing the most important contributors to the provenance of its ATcT enthalpy of formation, other highly correlated chemical species, and high-leverage reactions in the Thermochemical Network.
(Please note that, as opposed to traditional sequential thermochemistry where the provenance of a given enthalpy of formation is typically a single measurement,
the provenances of ATcT enthalpies of formation, which are obtained by analysing and solving a large Thermochemical Network, are normally quite distributed.)
Reaction Search
The stoichiometry represents fractions as decimals, e.g. 0.5 O2, 1 H2, 1 H2O would represent 1/2 O2 + H2 → H2O
Species Name
Preferred Formula
Image
Δf H°(0 K)
Δf H°(298.15 K)
Uncertainty
Units
Relative Molecular Mass
ATcT ID
Dihydrogen H2 (g) 0 0 exact 2.01588 ± 0.00014 1333-74-0*0 Helium He (g) 0 0 exact 4.0026020 ± 0.0000020 7440-59-7*0 Carbon C (graphite) 0 0 exact 12.01070 ± 0.00080 7440-44-0*500 Dinitrogen N2 (g) 0 0 exact 28.01348 ± 0.00014 7727-37-9*0 Dioxygen O2 (g) 0 0 exact 31.99880 ± 0.00060 7782-44-7*0 Difluorine F2 (g) 0 0 exact 37.9968064 ± 0.0000010 7782-41-4*0 Neon Ne (g) 0 0 exact 20.17970 ± 0.00060 7440-01-9*0 Silicon Si (cr,l) 0 0 exact 28.08550 ± 0.00030 7440-21-3*500 Sulfur S (cr,l) 0 0 exact 32.0660 ± 0.0060 7704-34-9*500 Dichlorine Cl2 (g) 0 0 exact 70.9054 ± 0.0018 7782-50-5*0 Argon Ar (g) 0 0 exact 39.94800 ± 0.00100 7440-37-1*0 Dibromine Br2 (cr,l) 0 0 exact 159.8080 ± 0.0020 7726-95-6*500 Krypton Kr (g) 0 0 exact 83.8000 ± 0.1000 7439-90-9*0 Diiodine I2 (cr,l) 0 0 exact 253.808940 ± 0.000060 7553-56-2*500 Xenon Xe (g) 0 0 exact 131.2900 ± 0.0200 7440-63-3*0 Platinum Pt (cr,l) 0 0 exact 195.0780 ± 0.0020 7440-06-4*500 Radon Rn (g) 0 0 exact 222.0000 ± 0.1000 10043-92-2*0 Deuterium molecule D2 (g) 0 0 exact 4.02820355600 ± 0.00000000080 7782-39-0*0 Hydrogen atom H (g) 216.034 217.998 ± 0.000 kJ/mol 1.007940 ± 0.000070 12385-13-6*0 Carbon C (g) 711.393 716.878 ± 0.040 kJ/mol 12.01070 ± 0.00080 7440-44-0*0 Oxygen atom O (g) 246.844 249.229 ± 0.0021 kJ/mol 15.99940 ± 0.00030 17778-80-2*0 Methane CH4 (g) -66.540 -74.510 ± 0.043 kJ/mol 16.04246 ± 0.00085 74-82-8*0 Water H2O (cr,l) -286.273 -285.801 ± 0.022 kJ/mol 18.01528 ± 0.00033 7732-18-5*500 Nitrogen atom N (g) 470.582 472.445 ± 0.022 kJ/mol 14.006740 ± 0.000070 17778-88-0*0 Carbon dioxide CO2 (g) -393.111 -393.477 ± 0.015 kJ/mol 44.00950 ± 0.00100 124-38-9*0 Hydron H+ (g) 1528.084 1530.047 ± 0.000 kJ/mol 1.007391 ± 0.000070 12408-02-5*0 Water H2O (g) -238.903 -241.806 ± 0.022 kJ/mol 18.01528 ± 0.00033 7732-18-5*0 Ethane CH3CH3 (g) -68.39 -84.01 ± 0.12 kJ/mol 30.0690 ± 0.0017 74-84-0*0 Chlorine atom Cl (g) 119.621 121.302 ± 0.0011 kJ/mol 35.45270 ± 0.00090 22537-15-1*0 Fluorine atom F (g) 77.254 79.360 ± 0.017 kJ/mol 18.99840320 ± 0.00000050 14762-94-8*0 Ethylene CH2CH2 (g) 60.91 52.40 ± 0.11 kJ/mol 28.0532 ± 0.0016 74-85-1*0 Propane CH3CH2CH3 (g) -82.71 -104.99 ± 0.15 kJ/mol 44.0956 ± 0.0025 74-98-6*0 Methyl CH3 (g) 149.883 146.482 ± 0.049 kJ/mol 15.03452 ± 0.00083 2229-07-4*0 Methanol CH3OH (g) -189.96 -200.84 ± 0.14 kJ/mol 32.04186 ± 0.00090 67-56-1*0 Ammonia NH3 (g) -38.563 -45.556 ± 0.029 kJ/mol 17.03056 ± 0.00022 7664-41-7*0 Bromine atom Br (g) 117.925 111.863 ± 0.055 kJ/mol 79.90400 ± 0.00100 10097-32-2*0 Hydroxyl OH (g) 37.278 37.517 ± 0.022 kJ/mol 17.00734 ± 0.00031 3352-57-6*0 Formaldehyde CH2O (g) -105.380 -109.220 ± 0.094 kJ/mol 30.02598 ± 0.00087 50-00-0*0 Acetylene HCCH (g) 228.89 228.34 ± 0.12 kJ/mol 26.0373 ± 0.0016 74-86-2*0 Ethanol CH3CH2OH (g) -217.17 -234.89 ± 0.19 kJ/mol 46.0684 ± 0.0017 64-17-5*0 Carbon monoxide CO (g) -113.799 -110.518 ± 0.026 kJ/mol 28.01010 ± 0.00085 630-08-0*0 Hydrogen chloride HCl (g) -91.988 -92.172 ± 0.0062 kJ/mol 36.46064 ± 0.00090 7647-01-0*0 Benzene C6H6 (g) 100.70 83.19 ± 0.21 kJ/mol 78.1118 ± 0.0048 71-43-2*0 Iodine I (g) 107.157 106.757 ± 0.0021 kJ/mol 126.904470 ± 0.000030 14362-44-8*0 Propene CH3CHCH2 (g) 34.92 20.08 ± 0.18 kJ/mol 42.0797 ± 0.0024 115-07-1*0 Hydrogen fluoride HF (g) -272.679 -272.726 ± 0.018 kJ/mol 20.006343 ± 0.000070 7664-39-3*0 Ethyl CH3CH2 (g) 131.52 120.77 ± 0.20 kJ/mol 29.0611 ± 0.0016 2025-56-1*0 Hydrogen cyanide HCN (g) 129.688 129.303 ± 0.087 kJ/mol 27.02538 ± 0.00081 74-90-8*0 Hydrogen bromide HBr (g) -27.51 -35.36 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*0 Nitric oxide NO (g) 90.622 91.126 ± 0.064 kJ/mol 30.00614 ± 0.00031 10102-43-9*0 Methylamine CH3NH2 (g) -6.45 -21.16 ± 0.22 kJ/mol 31.05714 ± 0.00088 74-89-5*0 Acetaldehyde CH3CHO (g) -154.86 -165.39 ± 0.22 kJ/mol 44.0526 ± 0.0017 75-07-0*0 Propyne CH3CCH (g) 192.73 185.58 ± 0.20 kJ/mol 40.0639 ± 0.0024 74-99-7*0 Chloromethane CH3Cl (g) -74.65 -82.58 ± 0.17 kJ/mol 50.4872 ± 0.0012 74-87-3*0 Acetone CH3C(O)CH3 (g) -199.92 -216.87 ± 0.26 kJ/mol 58.0791 ± 0.0025 67-64-1*0 Silicon Si (g) 450.34 454.68 ± 0.56 kJ/mol 28.08550 ± 0.00030 7440-21-3*0 Dioxidanyl HOO (g) 15.07 12.16 ± 0.14 kJ/mol 33.00674 ± 0.00060 3170-83-0*0 Hydrogen iodide HI (g) 28.646 26.471 ± 0.036 kJ/mol 127.912410 ± 0.000076 10034-85-2*0 Hydroxyde [OH]- (g) -139.064 -139.030 ± 0.022 kJ/mol 17.00789 ± 0.00031 14280-30-9*0 Allene CH2CCH2 (g) 197.50 190.04 ± 0.22 kJ/mol 40.0639 ± 0.0024 463-49-0*0 Nitrogen dioxide ONO (g) 36.861 34.054 ± 0.064 kJ/mol 46.00554 ± 0.00060 10102-44-0*0 Vinyl CH2CH (g) 301.26 297.22 ± 0.27 kJ/mol 27.0452 ± 0.0016 2669-89-8*0 Methylene CH2 (g, triplet) 391.076 391.622 ± 0.094 kJ/mol 14.02658 ± 0.00081 2465-56-7*1 Hydrogen peroxide HOOH (g) -129.418 -135.404 ± 0.058 kJ/mol 34.01468 ± 0.00062 7722-84-1*0 Fluoromethane CH3F (g) -227.44 -235.47 ± 0.24 kJ/mol 34.03292 ± 0.00083 593-53-3*0 n-Butane CH3CH2CH2CH3 (g) -98.22 -125.53 ± 0.19 kJ/mol 58.1222 ± 0.0033 106-97-8*0 Toluene C6H5CH3 (g) 73.37 50.08 ± 0.31 kJ/mol 92.1384 ± 0.0056 108-88-3*0 Silane SiH4 (g) 42.66 33.04 ± 0.63 kJ/mol 32.11726 ± 0.00041 7803-62-5*0 Methylene CH2 (g, singlet) 428.74 429.15 ± 0.11 kJ/mol 14.02658 ± 0.00081 2465-56-7*2 Ozone OOO (g) 144.407 141.744 ± 0.039 kJ/mol 47.99820 ± 0.00090 10028-15-6*0 1,3-Butadiene CH2CHCHCH2 (g) 125.64 111.17 ± 0.29 kJ/mol 54.0904 ± 0.0032 106-99-0*0 Acetic acid CH3C(O)OH (g, syn) -418.43 -432.59 ± 0.32 kJ/mol 60.0520 ± 0.0017 64-19-7*1 Fluoride F- (g) -250.911 -249.126 ± 0.017 kJ/mol 18.99895178 ± 0.00000050 16984-48-8*0 Ammonium hydroxide NH4OH (aq, 1000 H2O) -366.37 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*839 Ketene CH2CO (g) -45.33 -48.39 ± 0.11 kJ/mol 42.0367 ± 0.0016 463-51-4*0 Nitrilomethyl CN (g) 436.73 440.02 ± 0.14 kJ/mol 26.01744 ± 0.00080 2074-87-5*0 Bromomethane CH3Br (g) -20.45 -35.85 ± 0.19 kJ/mol 94.9385 ± 0.0013 74-83-9*0 Methoxy CH3O (g) 28.98 21.61 ± 0.26 kJ/mol 31.03392 ± 0.00088 2143-68-2*0 Formic acid HC(O)OH (g, syn) -370.98 -378.30 ± 0.20 kJ/mol 46.0254 ± 0.0010 64-18-6*1 Ethylamine CH3CH2NH2 (g) -28.02 -49.79 ± 0.42 kJ/mol 45.0837 ± 0.0017 75-04-7*0 Phenyl C6H5 (g) 352.64 339.28 ± 0.60 kJ/mol 77.1039 ± 0.0048 2396-01-2*0 Hydrogen chloride HCl (aq, 100 H2O) -165.756 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*828 Acetonitrile CH3CN (g) 81.15 74.08 ± 0.23 kJ/mol 41.0520 ± 0.0016 75-05-8*0 Hydroxymethyl CH2OH (g) -10.10 -16.41 ± 0.28 kJ/mol 31.03392 ± 0.00088 2597-43-5*0 Sulfur dioxide OSO (g) -294.20 -296.74 ± 0.13 kJ/mol 64.0648 ± 0.0060 7446-09-5*0 Hydrogen iodide HI (aq, 5000 H2O) -56.640 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*844 Hydrogen fluoride HF (l) -303.199 ± 0.099 kJ/mol 20.006343 ± 0.000070 7664-39-3*590 Methoxide [CH3O]- (g) -122.41 -130.13 ± 0.26 kJ/mol 31.03447 ± 0.00088 3315-60-4*0 Propargyl CH2CCH (g) 354.11 351.52 ± 0.31 kJ/mol 39.0559 ± 0.0024 2932-78-7*0 iso-Butane CH(CH3)3 (g) -105.87 -134.47 ± 0.27 kJ/mol 58.1222 ± 0.0033 75-28-5*0 Acetic acid CH3C(O)OH (aq, 100 H2O) -484.65 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*828 Hypochlorous acid HOCl (g) -73.840 -76.780 ± 0.024 kJ/mol 52.46004 ± 0.00095 7790-92-3*0 Hydrogen bromide HBr (aq, 3000 H2O) -120.25 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*842 Ethynyl CCH (g) 563.76 567.87 ± 0.15 kJ/mol 25.0293 ± 0.0016 2122-48-7*0 Formic acid HC(O)OH (aq, 100 H2O) -425.26 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*828 Amidogen NH2 (g) 188.92 186.03 ± 0.11 kJ/mol 16.02262 ± 0.00016 13770-40-6*0 Tetrafluoromethane CF4 (g) -927.63 -933.60 ± 0.23 kJ/mol 88.00431 ± 0.00080 75-73-0*0 Formyl HCO (g) 41.390 41.764 ± 0.094 kJ/mol 29.01804 ± 0.00086 2597-44-6*0 Formamide CH(O)NH2 (g) -178.64 -189.00 ± 0.34 kJ/mol 45.04066 ± 0.00088 75-12-7*0 n-Propyl CH3CH2CH2 (g) 118.47 101.07 ± 0.39 kJ/mol 43.0877 ± 0.0024 2143-61-5*0 Cyclopropane CH2(CH2CH2) (g) 71.07 53.95 ± 0.32 kJ/mol 42.0797 ± 0.0024 75-19-4*0 Cyclopentadiene CH2(CHCHCHCH) (g) 151.90 134.78 ± 0.49 kJ/mol 66.1011 ± 0.0040 542-92-7*0 Dibromine Br2 (g) 45.70 30.90 ± 0.11 kJ/mol 159.8080 ± 0.0020 7726-95-6*0 Diiodine I2 (g) 65.497 62.417 ± 0.0041 kJ/mol 253.808940 ± 0.000060 7553-56-2*0 iso-Propyl CH3CHCH3 (g) 105.68 88.81 ± 0.38 kJ/mol 43.0877 ± 0.0024 2025-55-0*0 Ethenol CH2CHOH (g, syn) -113.27 -124.40 ± 0.37 kJ/mol 44.0526 ± 0.0017 557-75-5*1 Allyl CH2CHCH2 (g) 179.92 168.20 ± 0.33 kJ/mol 41.0718 ± 0.0024 1981-80-2*0 Acetyl CH3CO (g) -3.60 -10.17 ± 0.29 kJ/mol 43.0446 ± 0.0016 3170-69-2*0 Chloroethane CH3CH2Cl (g) -96.94 -111.53 ± 0.25 kJ/mol 64.5138 ± 0.0019 75-00-3*0 Chloride Cl- (g) -228.953 -227.346 ± 0.0021 kJ/mol 35.45325 ± 0.00090 16887-00-6*0 Methoxymethane CH3OCH3 (g) -166.39 -183.89 ± 0.35 kJ/mol 46.0684 ± 0.0017 115-10-6*0 Dioxymethyl CH2OO (g) 112.11 105.11 ± 0.33 kJ/mol 46.0254 ± 0.0010 56077-92-0*0 Methanimine CH2NH (g) 96.39 88.48 ± 0.34 kJ/mol 29.04126 ± 0.00083 2053-29-4*0 Ethylium [CH3CH2]+ (g) 915.19 903.11 ± 0.29 kJ/mol 29.0606 ± 0.0016 14936-94-8*0 Fluoroform CHF3 (g) -689.28 -696.23 ± 0.40 kJ/mol 70.01385 ± 0.00080 75-46-7*0 Oxomethylium [HCO]+ (g) 827.766 827.182 ± 0.094 kJ/mol 29.01749 ± 0.00086 17030-74-9*0 Trifluoromethyl CF3 (g) -465.14 -467.94 ± 0.42 kJ/mol 69.00591 ± 0.00080 2264-21-3*0 Methylidyne CH (g) 592.977 596.311 ± 0.081 kJ/mol 13.01864 ± 0.00080 3315-37-5*0 Methyl hydroperoxide CH3OOH (g) -114.82 -127.64 ± 0.42 kJ/mol 48.0413 ± 0.0010 3031-73-0*0 Phenol C6H5OH (g) -74.34 -92.93 ± 0.62 kJ/mol 94.1112 ± 0.0048 108-95-2*0 Tetrachloromethane CCl4 (g) -89.28 -91.45 ± 0.41 kJ/mol 153.8215 ± 0.0037 56-23-5*0 Benzaldehyde C6H5C(O)H (g) -19.16 -36.95 ± 0.68 kJ/mol 106.1219 ± 0.0056 100-52-7*0 Bromide Br- (g) -206.612 -212.674 ± 0.055 kJ/mol 79.90455 ± 0.00100 24959-67-9*0 Hypobromous acid HOBr (g) -51.27 -61.74 ± 0.48 kJ/mol 96.9113 ± 0.0010 13517-11-8*0 Iodomethane CH3I (g) 24.53 14.99 ± 0.16 kJ/mol 141.93899 ± 0.00083 74-88-4*0 Methylperoxy CH3OO (g) 22.56 13.11 ± 0.34 kJ/mol 47.0333 ± 0.0010 2143-58-0*0 Oxonium [H3O]+ (g) 605.89 599.14 ± 0.17 kJ/mol 19.02267 ± 0.00037 13968-08-6*0 Cyanoacetylene HCCCN (g) 372.26 374.00 ± 0.57 kJ/mol 51.0468 ± 0.0024 1070-71-9*0 Chlorooxidanyl ClO (g) 101.124 101.716 ± 0.035 kJ/mol 51.45210 ± 0.00095 14989-30-1*0 Iodide I- (g) -187.996 -188.396 ± 0.0021 kJ/mol 126.905019 ± 0.000030 20461-54-5*0 Nitric acid HON(O)O (g) -124.42 -134.13 ± 0.17 kJ/mol 63.01288 ± 0.00091 7697-37-2*0 Hydroxyformyl HOCO (g, trans) -181.14 -184.10 ± 0.40 kJ/mol 45.0174 ± 0.0010 2564-86-5*1 Vinyl chloride CH2CHCl (g) 29.41 21.82 ± 0.27 kJ/mol 62.4979 ± 0.0018 75-01-4*0 Glycine NH2CH2C(O)OH (g, syn-anti-anti) -377.67 -396.14 ± 0.55 kJ/mol 75.0666 ± 0.0017 56-40-6*1 Ammonium [NH4]+ (g) 643.01 631.70 ± 0.20 kJ/mol 18.03795 ± 0.00029 14798-03-9*0 Imidogen NH (g) 358.75 358.80 ± 0.16 kJ/mol 15.014680 ± 0.000099 13774-92-0*0 1-Hydroxyethyl CH3CHOH (g, gauche-anti) -42.70 -56.13 ± 0.46 kJ/mol 45.0605 ± 0.0017 2348-46-1*1 Dimethylamine (CH3)2NH (g) 4.66 -16.98 ± 0.45 kJ/mol 45.0837 ± 0.0017 124-40-3*0 Vinylacetylene CH2CHCCH (g) 296.48 289.72 ± 0.52 kJ/mol 52.0746 ± 0.0032 689-97-4*0 Sulfur trioxide OS(O)O (g) -389.75 -395.50 ± 0.24 kJ/mol 80.0642 ± 0.0061 7446-11-9*0 Oxirane O(CH2CH2) (g) -39.72 -52.27 ± 0.33 kJ/mol 44.0526 ± 0.0017 75-21-8*0 Ethoxide [CH3CH2O]- (g) -163.74 -178.68 ± 0.44 kJ/mol 45.0610 ± 0.0017 16331-64-9*0 Oxygen atom anion O- (g) 105.868 108.096 ± 0.0021 kJ/mol 15.99995 ± 0.00030 14337-01-0*0 1,3-Butadiyne HCCCCH (g) 458.40 460.13 ± 0.48 kJ/mol 50.0587 ± 0.0032 460-12-8*0 Methylium [CH3]+ (g) 1099.355 1095.412 ± 0.045 kJ/mol 15.03397 ± 0.00083 14531-53-4*0 Isocyanic acid HNCO (g) -115.93 -118.93 ± 0.28 kJ/mol 43.02478 ± 0.00086 75-13-8*0 Cyanamide NH2CN (g) 141.62 135.60 ± 0.78 kJ/mol 42.04006 ± 0.00082 420-04-2*0 Difluorophosgene CF2O (g) -603.34 -606.44 ± 0.40 kJ/mol 66.00691 ± 0.00085 353-50-4*0 Hypofluorous acid HOF (g) -84.38 -87.28 ± 0.19 kJ/mol 36.00574 ± 0.00031 14034-79-8*0 Nitric acid HON(O)O (aq, 1000 H2O) -206.20 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*839 Isobutene CH2C(CH3)2 (g) 4.31 -16.75 ± 0.32 kJ/mol 56.1063 ± 0.0032 115-11-7*0 2-Hydroxyethyl CH2CH2OH (g, gauche-syn) -12.87 -26.13 ± 0.48 kJ/mol 45.0605 ± 0.0017 4422-54-2*1 N-Methylenemethanamine CH3NCH2 (g) 94.61 79.69 ± 0.67 kJ/mol 43.0678 ± 0.0016 1761-67-7*0 Dichloromethane CH2Cl2 (g) -86.84 -93.70 ± 0.33 kJ/mol 84.9320 ± 0.0020 75-09-2*0 Chlorobenzene C6H5Cl (g) 67.28 52.32 ± 0.61 kJ/mol 112.5566 ± 0.0049 108-90-7*0 Nitromethane CH3N(O)O (g) -60.58 -74.48 ± 0.40 kJ/mol 61.0401 ± 0.0010 75-52-5*0 Sulfur S (g) 276.84 279.08 ± 0.14 kJ/mol 32.0660 ± 0.0060 7704-34-9*0 Hydrogen chloride HCl (aq, 600 H2O) -166.450 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*834 Methylamidogen CH3NH (g) 187.99 177.34 ± 0.39 kJ/mol 30.04920 ± 0.00085 15622-51-2*0 Isocyanomethane CH3NC (g) 183.81 177.26 ± 0.47 kJ/mol 41.0520 ± 0.0016 593-75-9*0 1,2-Butadiene CH3CHCCH2 (g) 176.06 162.56 ± 0.42 kJ/mol 54.0904 ± 0.0032 590-19-2*0 Benzyl C6H5CH2 (g) 230.16 211.35 ± 0.51 kJ/mol 91.1305 ± 0.0056 2154-56-5*0 Cyclopentadienyl CH(CHCHCHCH) (g) 275.62 262.51 ± 0.80 kJ/mol 65.0932 ± 0.0040 2143-53-5*0 Ethyl hydroperoxide CH3CH2OOH (g) -142.47 -160.89 ± 0.62 kJ/mol 62.0678 ± 0.0018 3031-74-1*0 Ethynide [CCH]- (g) 277.32 280.73 ± 0.19 kJ/mol 25.0299 ± 0.0016 29075-95-4*0 Trimethylsilane SiH(CH3)3 (g) -125.8 -151.9 ± 1.5 kJ/mol 74.1970 ± 0.0025 993-07-7*0 Hydrogen sulfide H2S (g) -17.36 -20.29 ± 0.18 kJ/mol 34.0819 ± 0.0060 7783-06-4*0 Hydride H- (g) 143.264 145.228 ± 0.000 kJ/mol 1.008489 ± 0.000070 12184-88-2*0 Cyanogen chloride ClCN (g) 135.14 135.84 ± 0.43 kJ/mol 61.4701 ± 0.0012 506-77-4*0 Phenide [C6H5]- (g) 244.27 230.84 ± 0.38 kJ/mol 77.1044 ± 0.0048 30922-78-2*0 Cyclopropene CH2(CHCH) (g) 292.60 283.87 ± 0.41 kJ/mol 40.0639 ± 0.0024 2781-85-3*0 Formate [HC(O)O]- (g) -463.10 -466.74 ± 0.55 kJ/mol 45.0180 ± 0.0010 71-47-6*0 Methyl formate HC(O)OCH3 (g, syn) -346.82 -359.87 ± 0.61 kJ/mol 60.0520 ± 0.0017 107-31-3*1 Trihydrogen cation [H3]+ (g) 1110.304 1106.696 ± 0.013 kJ/mol 3.02327 ± 0.00021 28132-48-1*0 Fluoromethylidyne CF (g) 243.17 246.78 ± 0.11 kJ/mol 31.00910 ± 0.00080 3889-75-6*0 Acrolein CH2CHCHO (g, trans) -55.11 -65.51 ± 0.64 kJ/mol 56.0633 ± 0.0024 107-02-8*1 Sulfuric acid OS(O)(OH)2 (aq, 100 H2O) -887.52 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*828 Tetrafluorosilane SiF4 (g) -1608.76 -1614.27 ± 0.52 kJ/mol 104.07911 ± 0.00030 7783-61-1*0 Oxygen atom cation O+ (g) 1560.786 1562.643 ± 0.0021 kJ/mol 15.99885 ± 0.00030 14581-93-2*0 Nitrous acid HONO (g, trans) -72.988 -79.132 ± 0.077 kJ/mol 47.01348 ± 0.00061 7782-77-6*1 Hydroxymethylium [CH2OH]+ (g) 717.75 709.81 ± 0.18 kJ/mol 31.03337 ± 0.00088 18682-95-6*0 Cyanide [CN]- (g) 63.983 67.269 ± 0.091 kJ/mol 26.01799 ± 0.00080 57-12-5*0 2-Butyne CH3CCCH3 (g) 159.59 146.62 ± 0.45 kJ/mol 54.0904 ± 0.0032 503-17-3*0 Propynylidene HCCCH (g, triplet) 543.73 546.73 ± 0.58 kJ/mol 38.0480 ± 0.0024 67152-18-5*1 Difluoromethane CH2F2 (g) -443.32 -450.93 ± 0.35 kJ/mol 52.02339 ± 0.00081 75-10-5*0 Vinyl bromide CH2CHBr (g) 88.84 74.03 ± 0.54 kJ/mol 106.9492 ± 0.0019 593-60-2*0 Silyl SiH3 (g) 204.71 199.23 ± 0.80 kJ/mol 31.10932 ± 0.00037 13765-44-1*0 Sulfurous acid S(O)(OH)2 (aq, 2500 H2O) -617.29 ± 0.14 kJ/mol 82.0801 ± 0.0061 7782-99-2*898 Oxygen difluoride FOF (g) 26.80 24.55 ± 0.22 kJ/mol 53.99621 ± 0.00030 7783-41-7*0 Hypochlorite [ClO]- (g) -118.60 -118.33 ± 0.13 kJ/mol 51.45265 ± 0.00095 14380-61-1*0 Hypoiodous acid HOI (g) -53.6 -58.3 ± 2.8 kJ/mol 143.91181 ± 0.00031 14332-21-9*0 Nitrosyl hydride HNO (g) 109.93 106.96 ± 0.11 kJ/mol 31.01408 ± 0.00032 14332-28-6*0 Methylidyne CH (g, quartet) 664.92 668.26 ± 0.44 kJ/mol 13.01864 ± 0.00080 3315-37-5*2 Butatriene CH2CCCH2 (g) 328.44 322.18 ± 0.53 kJ/mol 52.0746 ± 0.0032 2873-50-9*0 Ethoxy CH3CH2O (g, X 2A") 1.39 -12.51 ± 0.42 kJ/mol 45.0605 ± 0.0017 2154-50-9*51 Vinoxy CH2CHO (g) 22.92 16.12 ± 0.53 kJ/mol 43.0446 ± 0.0016 6912-06-7*0 Ethylperoxy CH3CH2OO (g, gauche) -6.09 -22.11 ± 0.60 kJ/mol 61.0599 ± 0.0017 3170-61-4*3 Acetone enol CH3C(OH)CH2 (g, syn) -151.24 -168.53 ± 0.68 kJ/mol 58.0791 ± 0.0025 29456-04-0*1 Phosgene CCl2O (g) -217.49 -219.18 ± 0.24 kJ/mol 98.9155 ± 0.0020 75-44-5*0 1-Hydroxy-2-propanone CH3C(O)CH2OH (g, syn-syn) -354.40 -373.79 ± 0.83 kJ/mol 74.0785 ± 0.0025 116-09-6*11 Cyanoamidogen HNCN (g, doublet) 322.73 320.24 ± 0.63 kJ/mol 41.03212 ± 0.00082 12347-01-2*1 Chloroform CHCl3 (g) -94.51 -99.42 ± 0.39 kJ/mol 119.3767 ± 0.0028 67-66-3*0 Tetrafluoroethylene CF2CF2 (g) -670.66 -674.06 ± 0.47 kJ/mol 100.0150 ± 0.0016 116-14-3*0 Benzoyl C6H5CO (g) 138.85 125.32 ± 0.98 kJ/mol 105.1140 ± 0.0056 2652-65-5*0 Methyl nitrite CH3ONO (g, cis) -54.33 -66.11 ± 0.69 kJ/mol 61.0401 ± 0.0010 624-91-9*2 Acrylonitrile CH2CHCN (g, singlet) 194.02 187.26 ± 0.60 kJ/mol 53.0627 ± 0.0024 107-13-1*1 Silanol SiH3OH (g) -271.0 -282.7 ± 1.2 kJ/mol 48.11666 ± 0.00051 14475-38-8*0 Naphthalene C6H4(C4H4) (g) 171.17 147.69 ± 0.54 kJ/mol 128.1705 ± 0.0080 91-20-3*0 1,2-Propadiene-1,3-diylidene CCC (g) 814.40 823.36 ± 0.49 kJ/mol 36.0321 ± 0.0024 12075-35-3*0 Vinyl anion [CH2CH]- (g) 237.00 232.58 ± 0.68 kJ/mol 27.0458 ± 0.0016 25012-81-1*0 Cyanogen bromide BrCN (g) 186.8 180.2 ± 1.4 kJ/mol 105.9214 ± 0.0013 506-68-3*0 n-Butyl CH3CH2CH2CH2 (g) 103.10 80.60 ± 0.60 kJ/mol 57.1143 ± 0.0033 2492-36-6*0 neo-Pentane C(CH3)4 (g) -134.25 -167.12 ± 0.38 kJ/mol 72.1488 ± 0.0041 463-82-1*0 trans-2-Butene CH3CHCHCH3 (g, trans) 9.69 -10.88 ± 0.28 kJ/mol 56.1063 ± 0.0032 624-64-6*0 1-Butene CH2CHCH2CH3 (g) 21.24 0.29 ± 0.33 kJ/mol 56.1063 ± 0.0032 106-98-9*0 n-Hexane CH3CH2CH2CH2CH2CH3 (g) -129.89 -166.76 ± 0.32 kJ/mol 86.1754 ± 0.0049 110-54-3*0 Vinyl hydroperoxide CH2CHOOH (g, perp-syn) -26.04 -38.32 ± 0.69 kJ/mol 60.0520 ± 0.0017 66998-78-5*1 Propionaldehyde CH3CH2CHO (g) -171.09 -186.50 ± 0.20 kJ/mol 58.0791 ± 0.0025 123-38-6*0 Methyl acetate CH3C(O)OCH3 (g, syn) -394.13 -413.00 ± 0.56 kJ/mol 74.0785 ± 0.0025 79-20-9*1 Acetonyl CH3C(O)CH2 (g) -18.39 -31.99 ± 0.62 kJ/mol 57.0712 ± 0.0024 3122-07-4*0 Aziridine NH(CH2CH2) (g) 143.58 127.05 ± 0.85 kJ/mol 43.0678 ± 0.0016 151-56-4*0 Tetrabromomethane CBr4 (g) 144.80 115.10 ± 0.73 kJ/mol 331.6267 ± 0.0041 558-13-4*0 Ethyl bromide CH3CH2Br (g) -40.97 -62.92 ± 0.24 kJ/mol 108.9651 ± 0.0019 74-96-4*0 Propadienone CH2CCO (g) 132.23 130.59 ± 0.61 kJ/mol 54.0474 ± 0.0024 61244-93-7*0 Chlorine fluoride ClF (g) -55.622 -55.717 ± 0.030 kJ/mol 54.45110 ± 0.00090 7790-89-8*0 Diazynium [NNH]+ (g) 1042.57 1038.96 ± 0.67 kJ/mol 29.02087 ± 0.00016 12357-66-3*0 Nitrite [ONO]- (g) -182.63 -185.44 ± 0.46 kJ/mol 46.00609 ± 0.00060 14797-65-0*0 Hydroxylamine NH2OH (g, trans) -33.06 -43.44 ± 0.42 kJ/mol 33.02996 ± 0.00037 7803-49-8*1 Vinylidene CCH2 (g) 411.24 412.15 ± 0.30 kJ/mol 26.0373 ± 0.0016 2143-69-3*0 Aminomethyl CH2NH2 (g) 159.42 149.58 ± 0.35 kJ/mol 30.04920 ± 0.00085 10507-29-6*0 cis-2-Butene CH3CHCHCH3 (g, cis) 14.43 -6.84 ± 0.38 kJ/mol 56.1063 ± 0.0032 590-18-1*0 1-Butyne CH3CH2CCH (g) 180.43 166.84 ± 0.56 kJ/mol 54.0904 ± 0.0032 107-00-6*0 Formic acid HC(O)OH (g) -370.98 -378.27 ± 0.20 kJ/mol 46.0254 ± 0.0010 64-18-6*0 Acetate [CH3C(O)O]- (g) -495.87 -505.00 ± 0.76 kJ/mol 59.0446 ± 0.0017 71-50-1*0 Methanetetraylbisamidogen NCN (g) 451.40 451.81 ± 0.40 kJ/mol 40.02418 ± 0.00081 2669-76-3*0 Bromoform CHBr3 (g) 80.98 54.83 ± 0.70 kJ/mol 252.7306 ± 0.0031 75-25-2*0 Vinyl fluoride CH2CHF (g) -134.50 -142.31 ± 0.45 kJ/mol 46.0436 ± 0.0016 75-02-5*0 Phenylium [C6H5]+ (g) 1149.32 1136.54 ± 0.85 kJ/mol 77.1034 ± 0.0048 17333-73-2*0 Indene C6H4(CHCHCH2) (g) 183.80 159.91 ± 0.72 kJ/mol 116.1598 ± 0.0072 95-13-6*0 Fluorobenzene C6H5F (g) -96.04 -111.71 ± 0.39 kJ/mol 96.1023 ± 0.0048 462-06-6*0 Ethyl nitrite CH3CH2ONO (g, trans-cis) -79.93 -98.67 ± 0.86 kJ/mol 75.0666 ± 0.0017 109-95-5*1 Fluorooxidanyl FO (g) 110.28 110.90 ± 0.14 kJ/mol 34.99780 ± 0.00030 12061-70-0*0 Nitrous oxide NNO (g) 86.020 82.591 ± 0.096 kJ/mol 44.01288 ± 0.00033 10024-97-2*0 Azanide [NH2]- (g) 114.65 111.77 ± 0.29 kJ/mol 16.02317 ± 0.00016 17655-31-1*0 Methanium [CH5]+ (g) 922.03 911.78 ± 0.44 kJ/mol 17.04985 ± 0.00087 15135-49-6*0 Peroxynitrous acid HOONO (g, cis, cis) -5.74 -14.18 ± 0.35 kJ/mol 63.01288 ± 0.00091 14691-52-2*3 Ethylidene CH3CH (g, triplet) 361.31 354.30 ± 0.48 kJ/mol 28.0532 ± 0.0016 4218-50-2*1 Ethylidene CH3CH (g, singlet) 373.66 366.43 ± 0.56 kJ/mol 28.0532 ± 0.0016 4218-50-2*2 Aminomethylium [CH2NH2]+ (g) 763.62 751.65 ± 0.52 kJ/mol 30.04865 ± 0.00085 488821-23-4*0 Cyanomethyl CH2CN (g) 262.84 259.96 ± 0.53 kJ/mol 40.0440 ± 0.0016 2932-82-3*0 Cyanic fluoride FCN (g) 8.49 8.82 ± 0.74 kJ/mol 45.01584 ± 0.00080 1495-50-7*0 Propadienylidene CH2CC (g) 554.47 555.61 ± 0.39 kJ/mol 38.0480 ± 0.0024 60731-10-4*0 t-Butyl (CH3)3C (g) 75.36 50.07 ± 0.68 kJ/mol 57.1143 ± 0.0033 1605-73-8*0 n-Pentane CH3CH2CH2CH2CH3 (g) -114.16 -146.04 ± 0.29 kJ/mol 72.1488 ± 0.0041 109-66-0*0 Methanediol CH2(OH)2 (g, C2 gauche) -378.49 -392.43 ± 0.62 kJ/mol 48.0413 ± 0.0010 463-57-0*1 Formic acid HC(O)OH (g, anti) -354.65 -361.75 ± 0.37 kJ/mol 46.0254 ± 0.0010 64-18-6*2 Cyanooxidanyl NCO (g) 126.96 127.44 ± 0.33 kJ/mol 42.01684 ± 0.00086 22400-26-6*0 Acetic acid CH3C(O)OH (g) -418.43 -432.59 ± 0.32 kJ/mol 60.0520 ± 0.0017 64-19-7*0 Ethenamine CH2CHNH2 (g) 69.39 54.83 ± 0.66 kJ/mol 43.0678 ± 0.0016 593-67-9*0 Fluoroethane CH3CH2F (g) -257.24 -272.10 ± 0.35 kJ/mol 48.0595 ± 0.0016 353-36-6*0 Chlorotrifluoromethane CF3Cl (g) -704.26 -709.37 ± 0.56 kJ/mol 104.4586 ± 0.0012 75-72-9*0 Pyridine N(CHCHCHCHCH) (g) 157.34 140.53 ± 0.40 kJ/mol 79.0999 ± 0.0040 110-86-1*0 Carbamoyl NH2CO (g) -7.73 -14.14 ± 0.72 kJ/mol 44.03272 ± 0.00087 2858-51-7*0 Acrylonitrile CH2CHCN (g) 194.02 187.26 ± 0.60 kJ/mol 53.0627 ± 0.0024 107-13-1*0 1,2,3-Butatrien-1-yl CH2CCCH (g) 497.55 497.57 ± 0.66 kJ/mol 51.0666 ± 0.0032 22112-56-7*0 Disilane SiH3SiH3 (g) 92.0 75.9 ± 1.3 kJ/mol 62.21864 ± 0.00073 1590-87-0*0 2,4-Hexadiyne CH3CCCCCH3 (g) 380.37 370.34 ± 0.82 kJ/mol 78.1118 ± 0.0048 2809-69-0*0 Bromooxidanyl BrO (g) 131.22 123.68 ± 0.28 kJ/mol 95.9034 ± 0.0010 15656-19-6*0 Aminooxy NH2O (g) 70.65 64.05 ± 0.62 kJ/mol 32.02202 ± 0.00034 13408-29-2*0 Hydroxyamidogen HNOH (g, trans) 101.27 94.43 ± 0.83 kJ/mol 32.02202 ± 0.00034 13940-32-4*1 Dioxygen cation [O2]+ (g) 1164.585 1165.221 ± 0.0092 kJ/mol 31.99825 ± 0.00060 12185-07-8*0 Ethynylene C2 (g) 819.984 828.450 ± 0.085 kJ/mol 24.0214 ± 0.0016 12070-15-4*0 Ethanide [CH3CH2]- (g) 155.44 144.36 ± 0.87 kJ/mol 29.0616 ± 0.0016 25013-41-6*0 Vinylium [CH2CH]+ (g) 1119.20 1115.75 ± 0.52 kJ/mol 27.0447 ± 0.0016 14604-48-9*0 Hydroxymethylene HCOH (g, trans) 112.70 108.93 ± 0.27 kJ/mol 30.02598 ± 0.00087 19710-56-6*1 Carbonic acid C(O)(OH)2 (g, cis-cis) -602.24 -612.42 ± 0.55 kJ/mol 62.0248 ± 0.0012 463-79-6*1 Peroxyformic acid HC(O)OOH (g, cis) -279.20 -288.55 ± 0.63 kJ/mol 62.0248 ± 0.0012 107-32-4*1 1,2-Propadienyl anion [CH2CCH]- (g) 266.10 263.04 ± 0.63 kJ/mol 39.0565 ± 0.0024 64066-06-4*0 1-Propanol CH3CH2CH2OH (g) -231.13 -254.97 ± 0.20 kJ/mol 60.0950 ± 0.0025 71-23-8*0 Cyclopentane CH2(CH2CH2CH2CH2) (g) -43.37 -75.94 ± 0.38 kJ/mol 70.1329 ± 0.0041 287-92-3*0 2-Ethylidenedioxidan-2-ium-1-ide CH3CHOO (g, syn) 51.25 37.79 ± 0.54 kJ/mol 60.0520 ± 0.0017 68941-70-8*2 Phenolate [C6H5O]- (g) -145.96 -161.42 ± 0.81 kJ/mol 93.1038 ± 0.0048 3229-70-7*0 (1E)-Ethanimine CH3CHNH (g, trans) 55.81 39.60 ± 0.72 kJ/mol 43.0678 ± 0.0016 56003-81-7*0 Diazomethyl HCNN (g, doublet) 467.86 465.31 ± 0.68 kJ/mol 41.03212 ± 0.00082 20813-32-5*1 Bromotrifluoromethane CF3Br (g) -638.62 -650.74 ± 0.39 kJ/mol 148.9099 ± 0.0013 75-63-8*0 Tetrahedrane CH(CH(CHCH)) (g) 547.73 539.32 ± 0.91 kJ/mol 52.0746 ± 0.0032 157-39-1*0 Silylene SiH2 (g, singlet) 271.60 269.94 ± 0.81 kJ/mol 30.10138 ± 0.00033 13825-90-6*2 Chlorine dioxide OClO (g) 101.42 98.95 ± 0.29 kJ/mol 67.4515 ± 0.0011 10049-04-4*0 Hypobromite [BrO]- (g) -95.99 -103.47 ± 0.53 kJ/mol 95.9039 ± 0.0010 14380-62-2*0 Nitrogen trifluoride NF3 (g) -125.84 -131.56 ± 0.55 kJ/mol 71.001950 ± 0.000070 7783-54-2*0 (E)-Diazene HNNH (g, trans) 207.17 200.03 ± 0.40 kJ/mol 30.02936 ± 0.00020 15626-43-4*0 (E)-Iminomethyl HCNH (g, trans) 275.80 272.19 ± 0.56 kJ/mol 28.03332 ± 0.00082 54980-10-8*0 Cyanogen NCCN (g) 308.19 310.14 ± 0.41 kJ/mol 52.0349 ± 0.0016 460-19-5*0 Water H2O (l) -285.801 ± 0.022 kJ/mol 18.01528 ± 0.00033 7732-18-5*590 Peroxyformyl HC(O)OO (g, syn) -100.40 -105.71 ± 0.67 kJ/mol 61.0168 ± 0.0012 56240-83-6*1 1-Methylethenyl CH3CCH2 (g) 263.05 252.65 ± 0.61 kJ/mol 41.0718 ± 0.0024 15552-77-9*0 Cyclopentene CH2(CH2CHCHCH2) (g) 59.94 35.67 ± 0.43 kJ/mol 68.1170 ± 0.0040 142-29-0*0 Trioxidane HOOOH (g, trans) -81.75 -90.59 ± 0.40 kJ/mol 50.01408 ± 0.00091 14699-99-1*1 Dioxirane CH2(OO) (g) 9.43 1.76 ± 0.37 kJ/mol 46.0254 ± 0.0010 157-26-6*0 Trimethylamine (CH3)3N (g) 2.70 -26.16 ± 0.78 kJ/mol 59.1103 ± 0.0025 75-50-3*0 Diazomethane CH2NN (g) 273.63 267.36 ± 0.86 kJ/mol 42.04006 ± 0.00082 334-88-3*0 Dichloromethylene CCl2 (g, singlet) 229.88 231.06 ± 0.64 kJ/mol 82.9161 ± 0.0020 1605-72-7*2 Trifluoromethylium [CF3]+ (g) 409.81 406.60 ± 0.41 kJ/mol 69.00536 ± 0.00080 18851-76-8*0 Glycine NH2CH2C(O)OH (aq) -470.09 ± 0.21 kJ/mol 75.0666 ± 0.0017 56-40-6*800 Methylketene CH3CHCO (g) -54.10 -63.58 ± 0.63 kJ/mol 56.0633 ± 0.0024 6004-44-0*0 Disilene SiH2SiH2 (g, singlet) 288.8 280.2 ± 1.7 kJ/mol 60.20276 ± 0.00066 15435-77-5*2 1,3-Pentadiyne HCCCCCH3 (g) 418.20 413.98 ± 0.65 kJ/mol 64.0853 ± 0.0040 4911-55-1*0 Disulfur S2 (g) 127.38 127.69 ± 0.27 kJ/mol 64.1320 ± 0.0120 23550-45-0*0 Sulfuric acid OS(O)(OH)2 (cr,l) -811.88 -813.87 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*500 Dimethyl sulfide CH3SCH3 (g) -20.22 -36.74 ± 0.35 kJ/mol 62.1350 ± 0.0062 75-18-3*0 Ozonide [OOO]- (g) -58.47 -60.83 ± 0.21 kJ/mol 47.99875 ± 0.00090 12596-80-4*0 Azido radical NNN (g) 452.38 449.79 ± 0.59 kJ/mol 42.02022 ± 0.00021 12596-60-0*0 Nitrosyl ion [NO]+ (g) 984.490 984.485 ± 0.064 kJ/mol 30.00559 ± 0.00031 14452-93-8*0 Hydroxyoxomethylium [HOCO]+ (g) 600.71 597.63 ± 0.43 kJ/mol 45.0169 ± 0.0010 638-71-1*0 Hydrazoic acid HNNN (g) 297.99 291.69 ± 0.48 kJ/mol 43.02816 ± 0.00022 7782-79-8*0 Difluorodioxidane FOOF (g) 35.38 31.65 ± 0.40 kJ/mol 69.99561 ± 0.00060 7783-44-0*0 Methylidyne CH (g, doublet) 592.977 596.311 ± 0.081 kJ/mol 13.01864 ± 0.00080 3315-37-5*1 Acetylium [CH3CO]+ (g) 666.71 659.42 ± 0.42 kJ/mol 43.0441 ± 0.0016 15762-07-9*0 Hydrogen isocyanide HNC (g) 192.07 192.45 ± 0.32 kJ/mol 27.02538 ± 0.00081 6914-07-4*0 Chloroacetylene HCCCl (g) 229.36 230.23 ± 0.45 kJ/mol 60.4820 ± 0.0018 593-63-5*0 Fluoroacetylene HCCF (g) 104.99 105.71 ± 0.39 kJ/mol 44.0277 ± 0.0016 2713-09-9*0 iso-Propylium [CH3CHCH3]+ (g) 822.99 805.91 ± 0.23 kJ/mol 43.0871 ± 0.0024 19252-53-0*0 1-Propenyl CH3CHCH (g, cis) 278.21 267.37 ± 0.63 kJ/mol 41.0718 ± 0.0024 6067-68-1*2 1-Hydroxyethylium [CH3CHOH]+ (g, anti) 608.90 594.48 ± 0.37 kJ/mol 45.0600 ± 0.0017 18682-96-7*1 Ketenyl HCCO (g) 177.11 178.20 ± 0.54 kJ/mol 41.0287 ± 0.0016 51095-15-9*0 Ethynol HCCOH (g, singlet) 95.32 92.83 ± 0.73 kJ/mol 42.0367 ± 0.0016 32038-79-2*2 Hydroxymethoxy CH2(OH)O (g, gauche) -159.58 -169.54 ± 0.84 kJ/mol 47.0333 ± 0.0010 72144-78-6*3 1-Butanol CH3CH2CH2CH2OH (g) -244.49 -274.74 ± 0.24 kJ/mol 74.1216 ± 0.0033 71-36-3*0 Acetic acid CH3C(O)OH (g, anti) -397.63 -412.04 ± 0.50 kJ/mol 60.0520 ± 0.0017 64-19-7*2 Glycolaldehyde HC(O)CH2OH (g, syn-syn) -304.28 -317.55 ± 0.89 kJ/mol 60.0520 ± 0.0017 141-46-8*11 Methyl formate HC(O)OCH3 (g, anti) -326.6 -339.0 ± 1.1 kJ/mol 60.0520 ± 0.0017 107-31-3*2 Glyoxal OCHCHO (g, trans) -207.82 -213.46 ± 0.54 kJ/mol 58.0361 ± 0.0017 107-22-2*1 (Methylamino)methyl CH3NHCH2 (g) 168.81 152.36 ± 0.70 kJ/mol 44.0758 ± 0.0017 31277-24-4*0 Diazirinyl HC(NN) (g, 2A2) 491.09 487.70 ± 0.96 kJ/mol 41.03212 ± 0.00082 69967-71-1*1 Diazirine CH2(NN) (g) 320.7 313.0 ± 1.1 kJ/mol 42.04006 ± 0.00082 157-22-2*0 Trichloromethyl CCl3 (g) 73.79 73.31 ± 0.84 kJ/mol 118.3688 ± 0.0028 3170-80-7*0 1,1-Dichloroethane CH3CHCl2 (g) -120.15 -132.92 ± 0.43 kJ/mol 98.9586 ± 0.0024 75-34-3*0 Dibromomethane CH2Br2 (g) 27.01 5.61 ± 0.59 kJ/mol 173.8346 ± 0.0022 74-95-3*0 Bromobenzene C6H5Br (g) 127.0 105.0 ± 1.3 kJ/mol 157.0079 ± 0.0049 108-86-1*0 Phenylethene C6H5CHCH2 (g) 169.91 148.57 ± 0.51 kJ/mol 104.1491 ± 0.0064 100-42-5*0 Phenylacetylene C6H5CCH (g) 332.81 317.65 ± 0.69 kJ/mol 102.1332 ± 0.0064 536-74-3*0 Phenoxy C6H5O (g) 71.50 56.22 ± 0.81 kJ/mol 93.1033 ± 0.0048 2122-46-5*0 Dioxidanide [HOO]- (g) -88.92 -91.58 ± 0.34 kJ/mol 33.00729 ± 0.00060 14691-59-9*0 Acetophenone C6H5C(O)CH3 (g) -60.71 -83.90 ± 0.98 kJ/mol 120.1485 ± 0.0064 98-86-2*0 Hydroxyde [OH]- (aq) -229.757 ± 0.023 kJ/mol 17.00789 ± 0.00031 14280-30-9*800 Nitrosomethane CH3NO (g) 80.95 71.04 ± 0.91 kJ/mol 45.04066 ± 0.00088 865-40-7*0 Isocyanoacetylene HCCNC (g) 484.80 487.03 ± 0.98 kJ/mol 51.0468 ± 0.0024 66723-45-3*0 Cyclobutadiene CH(CHCHCH) (g) 436.58 428.12 ± 0.63 kJ/mol 52.0746 ± 0.0032 1120-53-2*0 Fulvene CH2C(CHCHCHCH) (g) 232.2 216.1 ± 1.1 kJ/mol 78.1118 ± 0.0048 497-20-1*0 Disilanyl SiH3SiH2 (g) 242.4 230.4 ± 1.5 kJ/mol 61.21070 ± 0.00069 73151-72-1*0 Silanone SiH2O (g) -93.77 -99.12 ± 0.99 kJ/mol 46.10078 ± 0.00045 22755-01-7*0 Silyloxy SiH3O (g) 8.5 0.6 ± 1.4 kJ/mol 47.10872 ± 0.00047 81429-20-1*0 Sulfanyl SH (g) 142.81 143.27 ± 0.18 kJ/mol 33.0739 ± 0.0060 13940-21-1*0 Methanethiol CH3SH (g) -10.39 -20.66 ± 0.46 kJ/mol 48.1085 ± 0.0061 74-93-1*0 Chlorous acid HOClO (g) 25.77 20.71 ± 0.63 kJ/mol 68.4594 ± 0.0011 13898-47-0*0 Dioxygen anion [O2]- (g) -43.36 -42.72 ± 0.17 kJ/mol 31.99935 ± 0.00060 11062-77-4*0 Iodooxidanyl IO (g) 127.05 125.12 ± 0.82 kJ/mol 142.90387 ± 0.00030 14696-98-1*0 Iodotrifluoromethane CF3I (g) -583.19 -589.09 ± 0.45 kJ/mol 195.91038 ± 0.00080 2314-97-8*0 Carbon monoxide cation [CO]+ (g) 1238.311 1241.591 ± 0.026 kJ/mol 28.00955 ± 0.00085 12144-04-6*0 Hydrazine NH2NH2 (g) 111.75 97.60 ± 0.44 kJ/mol 32.04524 ± 0.00031 302-01-2*0 Nitrate [ON(O)O]- (g) -299.73 -306.28 ± 0.22 kJ/mol 62.00549 ± 0.00090 14797-55-8*0 Methanide [CH3]- (g) 141.16 137.72 ± 0.24 kJ/mol 15.03507 ± 0.00083 15194-58-8*0 Methyleneamidogen CH2N (g) 242.08 238.43 ± 0.55 kJ/mol 28.03332 ± 0.00082 15845-29-1*0 Hypofluorite [FO]- (g) -108.84 -108.67 ± 0.48 kJ/mol 34.99835 ± 0.00030 12763-66-5*0 Cyanogen iodide ICN (g) 222.5 222.0 ± 1.7 kJ/mol 152.92191 ± 0.00080 506-78-5*0 Formyl anion [HCO]- (g) 11.60 11.98 ± 0.44 kJ/mol 29.01859 ± 0.00086 57340-31-5*0 n-Propylium [CH3CH2CH2]+ (g) 857.17 838.89 ± 0.76 kJ/mol 43.0871 ± 0.0024 19252-52-9*0 Cyclopropyl CH(CH2CH2) (g) 303.91 291.29 ± 0.48 kJ/mol 41.0718 ± 0.0024 2417-82-5*0 2-Propynylidyne CCCH (g) 718.79 723.14 ± 0.71 kJ/mol 37.0400 ± 0.0024 53590-28-6*0 iso-Pentane CH3CH2CH(CH3)2 (g) -118.90 -152.95 ± 0.39 kJ/mol 72.1488 ± 0.0041 78-78-4*0 1-Hydroxyethylidene CH3COH (g, anti singlet) 57.45 47.08 ± 0.77 kJ/mol 44.0526 ± 0.0017 30967-49-8*21 Dicarbon monoxide CCO (g, triplet) 377.13 381.17 ± 0.83 kJ/mol 40.0208 ± 0.0016 12071-23-7*1 Dimethylamidogen (CH3)2N (g) 175.07 157.73 ± 0.92 kJ/mol 44.0758 ± 0.0017 15337-44-7*0 2-Iminoethyl CH2CHNH (g, anti) 219.37 208.00 ± 0.86 kJ/mol 42.0599 ± 0.0016 73843-90-0*2 Isocyanoamidogen HNNC (g, doublet) 489.7 487.7 ± 1.2 kJ/mol 41.03212 ± 0.00082 947408-73-3*1 Fluorodioxidanyl FOO (g) 26.87 25.16 ± 0.26 kJ/mol 50.99720 ± 0.00060 15499-23-7*0 Chloromethylene CHCl (g, singlet) 320.36 320.65 ± 0.89 kJ/mol 48.4713 ± 0.0012 2108-20-5*2 1,1-Difluoroethene CH2CF2 (g) -343.59 -350.65 ± 0.63 kJ/mol 64.0341 ± 0.0016 75-38-7*0 Indane C6H4(CH2CH2CH2) (g) 90.89 59.86 ± 0.76 kJ/mol 118.1757 ± 0.0072 496-11-7*0 o-Tolualdehyde CH3C6H4C(O)H (g, ortho) -44.1 -66.4 ± 1.1 kJ/mol 120.1485 ± 0.0064 529-20-4*0 Carbamic acid NH2C(O)OH (g, syn) -421.82 -435.04 ± 0.83 kJ/mol 61.0401 ± 0.0010 463-77-4*1 3-Buten-2-one CH3C(O)CHCH2 (g, trans) -95.28 -111.52 ± 0.85 kJ/mol 70.0898 ± 0.0032 78-94-4*1 Urea NH2C(O)NH2 (g) -218.16 -234.56 ± 0.42 kJ/mol 60.05534 ± 0.00091 57-13-6*0 Oxomethaniminium [NH2CO]+ (g) 695.33 688.77 ± 0.89 kJ/mol 44.03217 ± 0.00087 59348-22-0*0 Acetamide CH3C(O)NH2 (g) -219.62 -237.13 ± 0.56 kJ/mol 59.0672 ± 0.0017 60-35-5*0 1-Cyanovinyl CH2CCN (g) 419.1 418.9 ± 1.1 kJ/mol 52.0547 ± 0.0024 15091-87-9*0 1,3-Hexadiyne HCCCCCH2CH3 (g) 405.25 393.56 ± 0.94 kJ/mol 78.1118 ± 0.0048 4447-21-6*0 (E)-1-Methylallyl CH3CHCHCH2 (g, trans) 152.70 135.38 ± 0.79 kJ/mol 55.0984 ± 0.0032 17787-86-9*0 Sulfuric acid OS(O)(OH)2 (aq, 1000 H2O) -892.23 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*839 Iodine monochloride ICl (g) 19.024 17.391 ± 0.013 kJ/mol 162.35717 ± 0.00090 7790-99-0*0 Hypoiodite [IO]- (g) -102.38 -104.19 ± 0.88 kJ/mol 142.90442 ± 0.00030 15065-65-3*0 Nitrogen atom cation N+ (g) 1872.910 1875.692 ± 0.022 kJ/mol 14.006191 ± 0.000070 14158-23-7*0 Trinitrogen cation [NNN]+ (g) 1519.59 1516.96 ± 0.89 kJ/mol 42.01967 ± 0.00021 12185-03-4*0 Oxonitrate anion [NO]- (g) 88.10 88.13 ± 0.25 kJ/mol 30.00669 ± 0.00031 14967-78-3*0 Nitrogen sesquioxide ONN(O)O (g) 90.73 86.16 ± 0.15 kJ/mol 76.01168 ± 0.00091 10544-73-7*0 Hexafluoroethane CF3CF3 (g) -1334.05 -1342.35 ± 0.80 kJ/mol 138.0118 ± 0.0016 76-16-4*0 Methyliumyl [CH2]+ (g) 1393.21 1394.07 ± 0.10 kJ/mol 14.02603 ± 0.00081 15091-72-2*0 Methylene anion [CH2]- (g) 328.18 328.61 ± 0.18 kJ/mol 14.02713 ± 0.00081 50928-07-9*0 Methylidyne anion [CH]- (g) 475.77 479.09 ± 0.21 kJ/mol 13.01919 ± 0.00080 28604-54-8*0 Ethanium [C2H7]+ (g, bridged C2) 874.39 858.13 ± 0.61 kJ/mol 31.0764 ± 0.0017 24669-33-8*1 Methylammonium [CH3NH3]+ (g) 628.36 609.45 ± 0.84 kJ/mol 32.06453 ± 0.00091 17000-00-9*0 Chlorine trifluoride FCl(F)F (g) -158.62 -162.72 ± 0.86 kJ/mol 92.44791 ± 0.00090 7790-91-2*0 Methylperoxy anion [CH3OO]- (g) -89.66 -99.81 ± 0.45 kJ/mol 47.0339 ± 0.0010 35683-44-4*0 Cyclobutane CH2(CH2CH2CH2) (g) 52.27 27.73 ± 0.36 kJ/mol 56.1063 ± 0.0032 287-23-0*0 2-Butynyl CH3CCCH2 (g) 318.18 310.81 ± 0.66 kJ/mol 53.0825 ± 0.0032 82252-88-8*0 1,2-Butadienyl CH3CHCCH (g) 328.98 320.26 ± 0.63 kJ/mol 53.0825 ± 0.0032 4777-46-2*0 Isoprene CH2C(CH3)CHCH2 (g) 96.29 75.77 ± 0.66 kJ/mol 68.1170 ± 0.0040 78-79-5*0 Oxirene O(CHCH) (g, singlet) 272.44 270.29 ± 0.60 kJ/mol 42.0367 ± 0.0016 157-18-6*2 Dihydroxymethyl CH(OH)2 (g, syn-anti) -196.9 -206.3 ± 1.1 kJ/mol 47.0333 ± 0.0010 14840-85-8*1 Formyloxidanyl HC(O)O (g, 2A1) -125.76 -127.42 ± 0.55 kJ/mol 45.0174 ± 0.0010 16499-21-1*1 Methoxyethane CH3CH2OCH3 (g) -194.27 -217.16 ± 0.52 kJ/mol 60.0950 ± 0.0025 540-67-0*0 Cyanoamidogen anion [HNCN]- (g, singlet) 69.75 66.74 ± 0.72 kJ/mol 41.03267 ± 0.00082 67131-47-9*2 1,1,1-Trichloroethane CH3CCl3 (g) -133.96 -144.53 ± 0.52 kJ/mol 133.4033 ± 0.0031 71-55-6*0 Tetrachloroethene CCl2CCl2 (g) -20.52 -21.38 ± 0.99 kJ/mol 165.8322 ± 0.0039 127-18-4*0 Chlorine atom cation Cl+ (g) 1370.807 1372.603 ± 0.0021 kJ/mol 35.45215 ± 0.00090 24203-47-2*0 Chlorodifluoromethane CHClF2 (g) -475.57 -481.76 ± 0.99 kJ/mol 86.4681 ± 0.0012 75-45-6*0 Fluoromethylene CHF (g, singlet) 148.40 148.69 ± 0.43 kJ/mol 32.01704 ± 0.00080 13453-52-6*2 Fluoroformyl FCO (g) -176.62 -176.03 ± 0.37 kJ/mol 47.00850 ± 0.00085 1871-24-5*0 2-Bromoethanol BrCH2CH2OH (g) -195.98 -220.04 ± 0.52 kJ/mol 124.9645 ± 0.0019 540-51-2*0 Carbon suboxide OCCCO (g) -94.41 -92.30 ± 0.96 kJ/mol 68.0309 ± 0.0025 504-64-3*0 Ethylbenzene C6H5CH2CH3 (g) 58.43 29.96 ± 0.52 kJ/mol 106.1650 ± 0.0064 100-41-4*0 m-Tolualdehyde CH3C6H4C(O)H (g, meta) -48.4 -71.3 ± 1.2 kJ/mol 120.1485 ± 0.0064 620-23-5*0 Glycine NH2CH2C(O)OH (g) -377.67 -394.70 ± 0.55 kJ/mol 75.0666 ± 0.0017 56-40-6*0 Methylcarbamic acid CH3NHC(O)OH (g, syn-anti) -414.50 -433.83 ± 0.92 kJ/mol 75.0666 ± 0.0017 6414-57-9*1 3-Oxo-1-propenyl CHCHCHO (g, anti-trans) 190.97 184.95 ± 0.91 kJ/mol 55.0553 ± 0.0024 206255-29-0*11 2-Propynal CHCCHO (g) 135.53 133.37 ± 0.87 kJ/mol 54.0474 ± 0.0024 624-67-9*0 Cyanomethylene HCCN (g, triplet) 479.6 483.0 ± 1.1 kJ/mol 39.0361 ± 0.0016 2612-62-6*1 3-Methylenecyclopropene CH2C(CHCH) (g) 396.11 388.18 ± 0.81 kJ/mol 52.0746 ± 0.0032 4095-06-1*0 Phenylperoxy C6H5OO (g) 154.0 137.0 ± 1.4 kJ/mol 109.1027 ± 0.0049 91422-02-5*0 Fluorosilylidyne SiF (g, doublet) -60.32 -58.48 ± 0.62 kJ/mol 47.08390 ± 0.00030 11128-24-8*1 Silylidyne SiH (g) 371.23 373.03 ± 0.67 kJ/mol 29.09344 ± 0.00031 13774-94-2*0 Bromosilane SiH3Br (g) -59.0 -75.5 ± 1.4 kJ/mol 111.0133 ± 0.0011 13465-73-1*0 Bromotrimethylsilane SiBr(CH3)3 (g) -259.4 -290.0 ± 2.0 kJ/mol 153.0931 ± 0.0027 2857-97-8*0 Trimethylsilylium [Si(CH3)3]+ (g) 655.4 634.8 ± 1.9 kJ/mol 73.1885 ± 0.0025 28927-31-3*0 1-Methyl-1-propenyl CH3CCHCH3 (g, trans) 240.12 223.95 ± 0.66 kJ/mol 55.0984 ± 0.0032 71790-71-1*1 1-Butenyl CH3CH2CHCH (g, cis) 263.48 246.14 ± 0.68 kJ/mol 55.0984 ± 0.0032 2669-61-6*2 Chloronium [HClH]+ (g) 881.5 878.4 ± 1.1 kJ/mol 37.46803 ± 0.00091 36658-55-6*0 Sulfur monoxide SO (g) 5.96 6.00 ± 0.13 kJ/mol 48.0654 ± 0.0060 13827-32-2*0 Iodine cation I+ (g) 1115.549 1115.149 ± 0.0062 kJ/mol 126.903921 ± 0.000030 22541-93-1*0 Ammonium [NH4]+ (aq) -133.076 ± 0.056 kJ/mol 18.03795 ± 0.00029 14798-03-9*800 Oxygen atom O (g, triplet) 246.844 249.229 ± 0.0021 kJ/mol 15.99940 ± 0.00030 17778-80-2*1 Ethylidyne CH3C (g, quartet) 641.0 636.4 ± 1.1 kJ/mol 27.0452 ± 0.0016 67624-57-1*2 Ethynylium [CCH]+ (g) 1687.65 1690.99 ± 0.15 kJ/mol 25.0288 ± 0.0016 16456-59-0*0 Isocyanomethanide [CH2NC]- (g) 254.00 250.96 ± 0.89 kJ/mol 40.0446 ± 0.0016 81704-80-5*0 Peroxyformate [HC(O)OO]- (g, syn) -340.93 -346.38 ± 0.80 kJ/mol 61.0174 ± 0.0012 104960-05-6*1 Hydrogen peroxide cation [HOOH]+ (g, trans) 897.30 890.32 ± 0.51 kJ/mol 34.01413 ± 0.00062 12325-10-9*1 1-Methylethylidene CH3CCH3 (g, singlet) 316.08 302.18 ± 0.97 kJ/mol 42.0797 ± 0.0024 40852-89-9*2 Propylidene CH3CH2CH (g, triplet gauche) 349.52 335.83 ± 0.92 kJ/mol 42.0797 ± 0.0024 6700-78-3*11 Cycloprop-2-enylium [CH(CHCH)]+ (g) 1080.47 1075.38 ± 0.99 kJ/mol 39.0554 ± 0.0024 26810-74-2*0 Trioxidanide [HOOO]- (g, gauche) -120.3 -123.4 ± 1.6 kJ/mol 49.00669 ± 0.00090 89965-38-8*2 Cyclobutene CH2(CH2CHCH) (g) 178.11 161.06 ± 0.60 kJ/mol 54.0904 ± 0.0032 822-35-5*0 1,3-Butadienyl CH2CHCHCH (g, trans-trans) 372.30 361.81 ± 0.87 kJ/mol 53.0825 ± 0.0032 86181-68-2*11 Cyclohexane CH2(CH2CH2CH2CH2CH2) (g) -83.21 -122.77 ± 0.29 kJ/mol 84.1595 ± 0.0049 110-82-7*0 Protonated oxirane [(CH2CH2)OH]+ (g) 725.75 709.58 ± 0.61 kJ/mol 45.0600 ± 0.0017 *38607-31-7*0 Methoxymethyl CH3OCH2 (g) 13.47 0.90 ± 0.86 kJ/mol 45.0605 ± 0.0017 16520-04-0*0 Methoxymethylene CH3OCH (g, anti singlet) 129.25 118.72 ± 0.78 kJ/mol 44.0526 ± 0.0017 19527-10-7*21 Oxirene O(CHCH) (g, t-triplet) 387.8 383.6 ± 1.3 kJ/mol 42.0367 ± 0.0016 157-18-6*11 Diethyl ether CH3CH2OCH2CH3 (g) -222.77 -250.19 ± 0.75 kJ/mol 74.1216 ± 0.0033 60-29-7*0 Cyanic acid HOCN (g) -12.32 -15.03 ± 0.43 kJ/mol 43.02478 ± 0.00086 420-05-3*0 Fulminic acid HCNO (g) 170.73 169.27 ± 0.44 kJ/mol 43.02478 ± 0.00086 51060-05-0*0 Isofulminic acid HONC (g) 235.25 233.55 ± 0.43 kJ/mol 43.02478 ± 0.00086 506-85-4*0 Nitrosomethylidyne CNO (g) 389.4 390.7 ± 1.1 kJ/mol 42.01684 ± 0.00086 82267-15-0*0 Acetyl chloride CH3C(O)Cl (g) -232.51 -241.50 ± 0.39 kJ/mol 78.4973 ± 0.0019 75-36-5*0 Dioxoethyl OCHCO (g) -63.26 -64.67 ± 0.86 kJ/mol 57.0281 ± 0.0017 702699-38-5*0 Chlorohydroxymethyl CH(Cl)OH (g, syn-gauche) -54.7 -60.7 ± 1.1 kJ/mol 65.4787 ± 0.0012 147139-06-8*1 1,1-Dichloroethene CH2CCl2 (g) 9.32 3.33 ± 0.50 kJ/mol 96.9427 ± 0.0024 75-35-4*0 Tetraiodomethane CI4 (g) 323.7 318.6 ± 1.1 kJ/mol 519.62858 ± 0.00081 507-25-5*0 Dichlorodifluoromethane CF2Cl2 (g) -488.87 -493.06 ± 0.44 kJ/mol 120.9129 ± 0.0020 75-71-8*0 Fluorodichloromethane CHFCl2 (g) -277.62 -283.07 ± 0.90 kJ/mol 102.9224 ± 0.0020 75-43-4*0 Difluoromethylene CF2 (g, singlet) -193.89 -193.41 ± 0.35 kJ/mol 50.00751 ± 0.00080 2154-59-8*2 Fluoromethylene CHF (g, triplet) 210.37 210.71 ± 0.65 kJ/mol 32.01704 ± 0.00080 13453-52-6*1 Formyl fluoride CHFO (g) -378.63 -382.22 ± 0.31 kJ/mol 48.01644 ± 0.00086 1493-02-3*0 Fulvenallene CH2CC(CHCHCHCH) (g, singlet) 368.7 354.4 ± 1.1 kJ/mol 90.1225 ± 0.0056 27041-32-3*2 Tropyl CH(CHCHCHCHCHCH) (g) 296.87 279.44 ± 0.94 kJ/mol 91.1305 ± 0.0056 3551-27-7*0 p-Tolualdehyde CH3C6H4C(O)H (g, para) -49.2 -72.2 ± 1.2 kJ/mol 120.1485 ± 0.0064 104-87-0*0 o-Toluoyl CH3C6H4CO (g, ortho) 110.4 91.9 ± 1.4 kJ/mol 119.1406 ± 0.0064 104680-89-9*0 Sulfur dioxide anion [OSO]- (g) -401.27 -403.53 ± 0.73 kJ/mol 64.0653 ± 0.0060 12143-17-8*0 2-Hydroxyprop-1-en-1-yl CH3C(OH)CH (g, trans-cis) 101.65 89.42 ± 0.86 kJ/mol 57.0712 ± 0.0024 1976041-84-5*11 Propyl nitrite CH3CH2CH2ONO (g, gauche-trans-cis) -94.5 -119.4 ± 1.7 kJ/mol 89.0932 ± 0.0025 543-67-9*1 1-Formylethenyl CH2CCHO (g) 177.62 172.09 ± 0.80 kJ/mol 55.0553 ± 0.0024 191018-90-3*0 2-Cyanovinyl CHCHCN (g, syn) 447.86 445.37 ± 0.98 kJ/mol 52.0547 ± 0.0024 189141-20-6*2 1,2,3-Butatrien-1-ylium [CH2CCCH]+ (g, singlet) 1271.9 1270.1 ± 1.1 kJ/mol 51.0661 ± 0.0032 81932-79-8*2 1-Buten-3-yn-1-yl HCCCHCH (g, trans) 547.40 544.73 ± 0.84 kJ/mol 51.0666 ± 0.0032 2810-61-9*1 3-Buten-1-ynyl CH2CHCC (g) 628.65 626.45 ± 0.99 kJ/mol 51.0666 ± 0.0032 108179-98-2*0 Methylsilane CH3SiH3 (g) -9.82 -25.99 ± 0.89 kJ/mol 46.14384 ± 0.00095 992-94-9*0 Fluorosilane SiH3F (g) -346.20 -355.60 ± 0.72 kJ/mol 50.10772 ± 0.00037 13537-33-2*0 Chlorosilane SiH3Cl (g) -126.5 -135.5 ± 1.4 kJ/mol 66.56202 ± 0.00097 13465-78-6*0 Tetramethylsilane Si(CH3)4 (g) -185.8 -216.2 ± 1.9 kJ/mol 88.2236 ± 0.0033 75-76-3*0 Hydroxysilyl SiH2OH (g) -104.1 -112.0 ± 1.5 kJ/mol 47.10872 ± 0.00047 113648-09-2*0 Trimethylsilanol (CH3)3SiOH (g) -465.2 -491.5 ± 1.9 kJ/mol 90.1964 ± 0.0025 1066-40-6*0 2-Aminoethyl CH2CH2NH2 (g) 174.49 158.03 ± 0.82 kJ/mol 44.0758 ± 0.0017 4422-53-1*0 2-Propanamine CH3CH(CH3)NH2 (g) -56.63 -83.43 ± 0.52 kJ/mol 59.1103 ± 0.0025 75-31-0*0 Bromanylium Br+ (g) 1257.786 1251.723 ± 0.056 kJ/mol 79.90345 ± 0.00100 22541-56-6*0 Sulfuric acid OS(O)(OH)2 (g) -715.5 -729.7 ± 1.1 kJ/mol 98.0795 ± 0.0061 7664-93-9*0 Dioxygen O2 (g, triplet) 0.000 0.000 ± 0.000 kJ/mol 31.99880 ± 0.00060 7782-44-7*1 Hydroperoxonium [H2OOH]+ (g, trans) 738.2 727.9 ± 1.2 kJ/mol 35.02207 ± 0.00064 70850-26-9*1 Dinitrogen cation [N2]+ (g) 1503.311 1503.312 ± 0.000 kJ/mol 28.01293 ± 0.00014 13966-04-6*0 Nitrogen atom N (g, quartet) 470.582 472.445 ± 0.022 kJ/mol 14.006740 ± 0.000070 17778-88-0*1 Chloro hypochlorite ClOCl (g) 79.79 77.98 ± 0.36 kJ/mol 86.9048 ± 0.0018 7791-21-1*0 Carbon dioxide cation [CO2]+ (g) 936.089 936.924 ± 0.017 kJ/mol 44.00895 ± 0.00100 12181-61-2*0 Xenon cation Xe+ (g) 1170.354 1170.354 ± 0.0062 kJ/mol 131.2895 ± 0.0200 24203-25-6*0 Nitroxyl ON(O)O (g) 79.38 74.12 ± 0.19 kJ/mol 62.00494 ± 0.00090 12033-49-7*0 Hydrazino NH2NH (g) 234.79 224.27 ± 0.69 kJ/mol 31.03730 ± 0.00025 13598-46-4*0 Nitryl hydride HN(O)O (g) -36.67 -43.64 ± 0.84 kJ/mol 47.01348 ± 0.00061 90266-90-3*0 Carbon anion C- (g) 589.616 594.763 ± 0.040 kJ/mol 12.01125 ± 0.00080 14337-00-9*0 Oxoniumyl ion [H2O]+ (g) 978.496 975.592 ± 0.024 kJ/mol 18.01473 ± 0.00033 56583-62-1*0 Chlorooxy hypochlorite ClOOCl (g) 134.58 131.34 ± 0.56 kJ/mol 102.9042 ± 0.0019 12292-23-8*0 Hydrogen isocyanide cation [HNC]+ (g) 1351.53 1351.49 ± 0.83 kJ/mol 27.02483 ± 0.00081 74158-11-5*0 Cyanomethanide [CH2CN]- (g) 113.69 110.87 ± 0.53 kJ/mol 40.0446 ± 0.0016 21438-99-3*0 Methyloxonium [CH3OH2]+ (g) 589.2 575.0 ± 1.1 kJ/mol 33.04925 ± 0.00092 17836-08-7*0 Chlorine pentafluoride FCl(F)(F)(F)F (g) -226.0 -234.1 ± 1.3 kJ/mol 130.44472 ± 0.00090 13637-63-3*0 n-Propylide [CH3CH2CH2]- (g) 123.1 105.5 ± 1.2 kJ/mol 43.0882 ± 0.0024 59513-13-2*0 Allyl anion [CH2CHCH2]- (g) 134.02 123.01 ± 0.21 kJ/mol 41.0723 ± 0.0024 1724-46-5*0 Propargylenide [HCCCH]- (g, transoid 2B) 434.5 437.0 ± 1.1 kJ/mol 38.0485 ± 0.0024 82906-05-6*1 2-Butyn-1-yl anion [CH3CCCH2]- (g) 253.8 244.9 ± 1.1 kJ/mol 53.0830 ± 0.0032 65114-66-1*0 Cycloheptatriene CH2(CHCHCHCHCHCH) (g) 207.82 184.40 ± 0.90 kJ/mol 92.1384 ± 0.0056 544-25-2*0 n-Octane CH3(CH2)6CH3 (g) -161.04 -207.88 ± 0.51 kJ/mol 114.2285 ± 0.0065 111-65-9*0 Ethoxy CH3CH2O (g, A 2A') 5.66 -8.77 ± 0.43 kJ/mol 45.0605 ± 0.0017 2154-50-9*52 Ethenol CH2CHOH (g, anti) -108.85 -119.56 ± 0.49 kJ/mol 44.0526 ± 0.0017 557-75-5*2 Hydroperoxymethyl CH2OOH (g) 73.26 65.96 ± 0.97 kJ/mol 47.0333 ± 0.0010 74087-87-9*0 Ketene CH2CO (g, singlet) -45.33 -48.39 ± 0.11 kJ/mol 42.0367 ± 0.0016 463-51-4*2 Oxiranyl CH2(CHO) (g) 172.78 164.50 ± 0.98 kJ/mol 43.0446 ± 0.0016 31586-84-2*0 Ketene CH2CO (g, triplet) 181.9 179.0 ± 1.1 kJ/mol 42.0367 ± 0.0016 463-51-4*1 Oxoethylidene HCC(O)H (g, syn-triplet) 261.1 257.6 ± 1.1 kJ/mol 42.0367 ± 0.0016 39920-84-8*12 Methoxyethene CH2CHOCH3 (g, cis) -89.3 -107.1 ± 1.1 kJ/mol 58.0791 ± 0.0025 107-25-5*2 2-Propanol CH3CH(OH)CH3 (g) -248.60 -272.70 ± 0.26 kJ/mol 60.0950 ± 0.0025 67-63-0*0 Methyl acetate CH3C(O)OCH3 (g, anti) -363.2 -382.0 ± 1.2 kJ/mol 74.0785 ± 0.0025 79-20-9*2 Carboxymethyl CH2C(O)OH (g, syn) -226.5 -236.4 ± 1.1 kJ/mol 59.0440 ± 0.0017 2887-46-9*1 1-Iminoethyl CH3CNH (g, anti) 233.1 223.0 ± 1.1 kJ/mol 42.0599 ± 0.0016 128365-64-0*2 1-Aminoethenyl CH2CNH2 (g) 294.71 286.08 ± 0.92 kJ/mol 42.0599 ± 0.0016 180385-92-6*0 Peroxyhypochlorous acid HOOCl (g) 3.97 -1.30 ± 0.95 kJ/mol 68.4594 ± 0.0011 67952-07-2*0 Dichloride [Cl2]- (g) -231.91 -230.84 ± 0.34 kJ/mol 70.9059 ± 0.0018 12595-89-0*0 Nitrilomethylimidogen NCHN (g, quartet) 581.6 578.4 ± 1.5 kJ/mol 41.03212 ± 0.00082 324529-58-0*2 Cyanoacetylide [CCCN]- (g) 300.4 305.7 ± 1.1 kJ/mol 50.0394 ± 0.0024 12373-53-4*0 Chloromethylidyne CCl (g) 430.64 434.39 ± 0.67 kJ/mol 47.4634 ± 0.0012 3889-76-7*0 Chloromethanol CH2(Cl)OH (g) -232.3 -242.6 ± 1.2 kJ/mol 66.4866 ± 0.0013 15454-33-8*0 Chloromethoxy CH2(Cl)O (g) -11.9 -18.7 ± 1.1 kJ/mol 65.4787 ± 0.0012 114282-89-2*0 Fluorotrichloromethane CCl3F (g) -283.23 -286.38 ± 0.76 kJ/mol 137.3672 ± 0.0028 75-69-4*0 Formyl chloride CHClO (g) -179.87 -183.07 ± 0.67 kJ/mol 64.4707 ± 0.0012 2565-30-2*0 2-Chloroethanol ClCH2CH2OH (g) -249.78 -266.49 ± 0.59 kJ/mol 80.5132 ± 0.0019 107-07-3*0 Butadiynyl CCCCH (g) 801.90 808.50 ± 0.96 kJ/mol 49.0507 ± 0.0032 53561-65-2*0 o-Benzyne C6H4 (g, singlet) 468.25 459.33 ± 0.86 kJ/mol 76.0960 ± 0.0048 462-80-6*2 m-Toluoyl CH3C6H4CO (g, meta) 109.4 90.8 ± 1.4 kJ/mol 119.1406 ± 0.0064 67958-04-7*0 Iodobenzene C6H5I (g) 178.62 162.64 ± 0.99 kJ/mol 204.0084 ± 0.0048 591-50-4*0 Furan O(CHCHCHCH) (g) -21.38 -34.51 ± 0.94 kJ/mol 68.0740 ± 0.0032 110-00-9*0 1-Hydroxy-1-methylethyl CH3C(OH)CH3 (g) -78.21 -96.46 ± 0.79 kJ/mol 59.0871 ± 0.0025 5131-95-3*0 Trifluoroethene CF2CHF (g) -493.5 -498.5 ± 1.4 kJ/mol 82.0245 ± 0.0016 359-11-5*0 Isocyanoethene CH2CHNC (g) 285.32 278.82 ± 0.92 kJ/mol 53.0627 ± 0.0024 14668-82-7*0 1-Isocyanoethylidene CH3CNC (g, singlet) 527.9 523.2 ± 1.1 kJ/mol 53.0627 ± 0.0024 *498544-34-6*2 2-Cyanovinyl CHCHCN (g, anti) 448.28 445.82 ± 0.97 kJ/mol 52.0547 ± 0.0024 189141-20-6*1 3-Methylene-1-cyclopropen-1-yl CH2C(CHC) (g) 628.3 625.7 ± 1.1 kJ/mol 51.0666 ± 0.0032 127611-24-9*0 Oxosilylene SiO (g) -98.37 -97.21 ± 0.54 kJ/mol 44.08490 ± 0.00042 10097-28-6*0 Silyloxy anion [SiH3O]- (g) -311.8 -321.1 ± 1.6 kJ/mol 47.10927 ± 0.00047 43336-62-5*0 Cyclobutyl CH(CH2CH2CH2) (g) 246.59 227.69 ± 0.72 kJ/mol 55.0984 ± 0.0032 4548-06-5*0 1-Ethynyl-2-propyn-1-yl CHCCHCCH (g) 577.09 575.47 ± 0.99 kJ/mol 63.0773 ± 0.0040 78596-35-7*0 1-Propanamine CH3CH2CH2NH2 (g) -42.20 -69.94 ± 0.42 kJ/mol 59.1103 ± 0.0025 107-10-8*0 Sulfurous acid S(O)(OH)2 (g, cis) -511.31 -521.52 ± 0.89 kJ/mol 82.0801 ± 0.0061 7782-99-2*2 Sulfo OS(OH)O (g) -366.9 -374.7 ± 1.1 kJ/mol 81.0721 ± 0.0061 32750-86-0*0 Dioxodiazoxane ONONO (g, t, t) 93.0 87.9 ± 1.3 kJ/mol 76.01168 ± 0.00091 122413-35-8*1 Nitric acid HON(O)O (aq) -206.52 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*800 Isodiazene NNH2 (g) 307.57 300.49 ± 0.60 kJ/mol 30.02936 ± 0.00020 28647-38-3*0 Oxoammoniumyl [HNO]+ (g) 1092.46 1089.54 ± 0.66 kJ/mol 31.01353 ± 0.00032 63559-87-5*0 Peroxynitrous acid HOONO (g, trans, perp) 7.83 0.75 ± 0.41 kJ/mol 63.01288 ± 0.00091 14691-52-2*1 Peroxynitric acid HOON(O)O (g) -41.46 -51.77 ± 0.32 kJ/mol 79.0123 ± 0.0012 26404-66-0*0 Tetrafluorohydrazine NF2NF2 (g, trans) -13.4 -22.9 ± 1.4 kJ/mol 104.00709 ± 0.00014 10036-47-2*1 Carbon cation C+ (g) 1797.845 1803.443 ± 0.040 kJ/mol 12.01015 ± 0.00080 14067-05-1*0 Ethylidyne CH3C (g) 508.65 504.95 ± 0.80 kJ/mol 27.0452 ± 0.0016 67624-57-1*0 Methylamidogen anion [CH3NH]- (g) 145.40 134.57 ± 0.64 kJ/mol 30.04975 ± 0.00085 54448-39-4*0 Methylimidogen CH3N (g) 323.0 315.3 ± 1.0 kJ/mol 29.04126 ± 0.00083 27770-42-9*0 Iminomethylium [HCNH]+ (g) 953.4 949.3 ± 1.4 kJ/mol 28.03277 ± 0.00082 196216-36-1*0 Hydrogen carbonate [HOC(O)O]- (g) -719.2 -725.6 ± 1.5 kJ/mol 61.0174 ± 0.0012 71-52-3*0 Cyclopropylide [CH(CH2CH2)]- (g) 265.4 252.6 ± 1.1 kJ/mol 41.0723 ± 0.0024 1724-45-4*0 Propylidyne CH3CH2C (g, doublet) 492.7 483.0 ± 1.2 kJ/mol 41.0718 ± 0.0024 85056-54-8*1 Cyclopropylidene C(CH2CH2) (g, singlet) 475.06 467.04 ± 0.84 kJ/mol 40.0639 ± 0.0024 2143-70-6*1 Propargylium [CH2CCH]+ (g) 1193.58 1190.77 ± 0.31 kJ/mol 39.0554 ± 0.0024 21540-27-2*0 Cycloprop-1-enyl CH2(CHC) (g) 527.52 523.13 ± 0.58 kJ/mol 39.0559 ± 0.0024 19528-44-0*0 Cyclopropenylidene C(CHCH) (g) 497.09 496.13 ± 0.45 kJ/mol 38.0480 ± 0.0024 16165-40-5*0 Propargylenide [HCCCH]- (g, cisoid 2A) 437.0 439.5 ± 1.1 kJ/mol 38.0485 ± 0.0024 82906-05-6*2 2-Propyn-1-ylium-1-ylidene [CCCH]+ (g) 1598.49 1602.87 ± 0.90 kJ/mol 37.0395 ± 0.0024 75104-46-0*0 sec-Butyl CH3CH2CHCH3 (g) 91.35 66.59 ± 0.71 kJ/mol 57.1143 ± 0.0033 2348-55-2*0 iso-Butyl (CH3)2CHCH2 (g) 97.34 73.35 ± 0.78 kJ/mol 57.1143 ± 0.0033 4630-45-9*0 1-Methylene-2-propenyl CH2CHCCH2 (g) 327.20 317.20 ± 0.74 kJ/mol 53.0825 ± 0.0032 1204515-52-5*0 2-Hydrotrioxy OO(H)O (g) 299.4 293.7 ± 1.2 kJ/mol 49.00614 ± 0.00090 *12500-78-6*0 n-Heptane CH3(CH2)5CH3 (g) -145.39 -187.26 ± 0.44 kJ/mol 100.2019 ± 0.0057 142-82-5*0 Oxoethanide [CH3CO]- (g) -44.0 -49.5 ± 1.3 kJ/mol 43.0452 ± 0.0016 78944-68-0*0 2-Hydroperoxyethyl CH2CH2OOH (g, gauche-syn) 64.8 50.4 ± 1.3 kJ/mol 61.0599 ± 0.0017 126898-97-3*32 Methoxyoxomethyl CH3OCO (g, anti-staggered) -152.8 -160.9 ± 1.1 kJ/mol 59.0440 ± 0.0017 16481-04-2*1 Water dimer (H2O)2 (g) -491.026 -499.066 ± 0.044 kJ/mol 36.03056 ± 0.00066 25655-83-8*0 Hydroxyformyl HOCO (g, cis) -174.33 -177.35 ± 0.48 kJ/mol 45.0174 ± 0.0010 2564-86-5*2 Hydroxyformyl anion [HOCO]- (g, cis) -319.53 -322.11 ± 0.56 kJ/mol 45.0180 ± 0.0010 78944-70-4*2 Ethyl formate HC(O)OCH2CH3 (g, syn) -375.0 -393.7 ± 1.0 kJ/mol 74.0785 ± 0.0025 109-94-4*1 Propionic acid CH3CH2C(O)OH (g, syn) -435.77 -453.67 ± 0.60 kJ/mol 74.0785 ± 0.0025 79-09-4*1 Fluoronium [HFH]+ (g, singlet) 774.04 771.10 ± 0.91 kJ/mol 21.01373 ± 0.00014 12206-67-6*2 Trioxidane HOOOH (g, cis) -72.67 -81.16 ± 0.78 kJ/mol 50.01408 ± 0.00091 14699-99-1*2 (Methylimino)methyl CH3NCH (g, trans) 278.0 267.9 ± 1.1 kJ/mol 42.0599 ± 0.0016 117928-23-1*1 1-Aziridinyl N(CH2CH2) (g) 314.0 301.8 ± 1.4 kJ/mol 42.0599 ± 0.0016 23838-09-7*0 (Dimethylamino)methyl (CH3)2NCH2 (g) 166.5 143.4 ± 1.3 kJ/mol 58.1024 ± 0.0025 30208-47-0*0 Cyanoamidogen HNCN (g, t-quartet) 652.4 649.6 ± 1.2 kJ/mol 41.03212 ± 0.00082 12347-01-2*21 Diazomethyl HCNN (g, c-quartet) 652.8 649.8 ± 1.3 kJ/mol 41.03212 ± 0.00082 20813-32-5*22 Diazomethanide [HCNN]- (g, singlet) 305.20 302.10 ± 0.76 kJ/mol 41.03267 ± 0.00082 100840-43-5*2 Isocyanoamidogen HNNC (g, c-quartet) 828.3 825.4 ± 1.3 kJ/mol 41.03212 ± 0.00082 947408-73-3*22 Ethylamidogen anion [CH3CH2NH]- (g) 106.55 88.90 ± 0.78 kJ/mol 44.0763 ± 0.0017 54448-40-7*0 Chloromethide [CH2Cl]- (g) 56.3 53.1 ± 2.0 kJ/mol 49.4798 ± 0.0012 60291-29-4*0 Hexachloroethane CCl3CCl3 (g) -144.1 -146.5 ± 1.3 kJ/mol 236.7376 ± 0.0056 67-72-1*0 cis-1,2-Dichloroethene CHClCHCl (g, cis) 3.83 -2.16 ± 0.55 kJ/mol 96.9427 ± 0.0024 156-59-2*0 Dichloroacetylene ClCCCl (g) 232.85 236.16 ± 0.72 kJ/mol 94.9268 ± 0.0024 7572-29-4*0 Iodoform CHI3 (g) 217.3 209.3 ± 1.6 kJ/mol 393.73205 ± 0.00081 75-47-8*0 Difluoromethylene CF2 (g) -193.89 -193.41 ± 0.35 kJ/mol 50.00751 ± 0.00080 2154-59-8*0 1,1-Difluoroethane CH3CHF2 (g) -489.00 -502.72 ± 0.53 kJ/mol 66.0500 ± 0.0016 75-37-6*0 Vinyl iodide CH2CHI (g) 139.64 130.80 ± 0.93 kJ/mol 153.9497 ± 0.0016 593-66-8*0 Bromoacetylene HCCBr (g) 287.5 281.0 ± 1.6 kJ/mol 104.9333 ± 0.0019 593-61-3*0 2-Fluoroethanol FCH2CH2OH (g) -405.62 -422.87 ± 0.99 kJ/mol 64.0589 ± 0.0017 371-62-0*0 1,3,5-Hexatriyne HCCCCCCH (g) 682.2 687.0 ± 1.2 kJ/mol 74.0801 ± 0.0048 3161-99-7*0 Benzylide [C6H5CH2]- (g) 142.01 123.10 ± 0.40 kJ/mol 91.1310 ± 0.0056 18860-15-6*0 Benzylidene C6H5CH (g, singlet) 489.6 474.5 ± 1.1 kJ/mol 90.1225 ± 0.0056 3101-08-4*2 Norbornadiene (CHCH)(CHCH2CH)(CHCH) (g) 265.0 239.6 ± 1.5 kJ/mol 92.1384 ± 0.0056 121-46-0*0 Benzonitrile C6H5CN (g) 230.00 215.80 ± 0.92 kJ/mol 103.1213 ± 0.0056 100-47-0*0 Perchloryl OCl(O)O (g) 191.77 186.10 ± 0.62 kJ/mol 83.4509 ± 0.0013 13932-10-0*0 p-Toluoyl CH3C6H4CO (g, para) 108.4 89.8 ± 1.4 kJ/mol 119.1406 ± 0.0064 67958-03-6*0 Acetonate [CH3C(O)CH2]- (g) -187.50 -201.06 ± 0.91 kJ/mol 57.0717 ± 0.0024 24262-31-5*0 Methyl nitrite CH3ONO (g) -54.33 -65.00 ± 0.69 kJ/mol 61.0401 ± 0.0010 624-91-9*0 Difluoride [F2]- (g) -290.6 -289.8 ± 1.3 kJ/mol 37.9973550 ± 0.0000010 12184-85-9*0 Chloric acid HOCl(O)O (g) 0.6 -6.5 ± 1.1 kJ/mol 84.4588 ± 0.0013 7790-93-4*0 Glycinate [NH2CH2C(O)O]- (g) -477.6 -493.3 ± 1.4 kJ/mol 74.0592 ± 0.0017 23297-34-9*0 Carboxymethanaminium [NH3CH2C(O)OH]+ (g) 270.0 246.7 ± 1.1 kJ/mol 76.0740 ± 0.0018 *56-40-6*0 Chlorate [OCl(O)O]- (g) -208.2 -213.7 ± 1.4 kJ/mol 83.4514 ± 0.0013 14866-68-3*0 cis-1,2-Diiodoethene CHICHI (g, cis) 217.57 209.28 ± 0.34 kJ/mol 279.8462 ± 0.0016 590-26-1*0 Acryloyl CH2CHCO (g, 2A") 102.80 97.21 ± 0.98 kJ/mol 55.0553 ± 0.0024 72241-20-4*2 3-Oxo-1,2-propadien-1-yl HCCCO (g) 290.36 292.87 ± 0.95 kJ/mol 53.0394 ± 0.0024 1198096-74-0*0 1-Cyanoethylidene CH3CCN (g, singlet) 475.7 470.6 ± 1.1 kJ/mol 53.0627 ± 0.0024 498544-34-6*2 3-Imino-2-propen-1-ylidene CHCHCNH (g, syn-singlet) 530.7 525.9 ± 1.2 kJ/mol 53.0627 ± 0.0024 916765-05-4*11 2-(Methylidyneamino)ethenyl CHCHNCH (g, anti-singlet) 600.7 595.7 ± 1.2 kJ/mol 53.0627 ± 0.0024 123416-74-0*11 1-Cyanovinyl anion [CH2CCN]- (g) 224.3 221.5 ± 1.2 kJ/mol 52.0553 ± 0.0024 36259-97-9*0 1,2,3-Butatrien-1-yl anion [CH2CCCH]- (g) 388.5 386.7 ± 1.1 kJ/mol 51.0672 ± 0.0032 102275-54-7*0 Difluorosilylene SiF2 (g, singlet) -629.1 -630.0 ± 1.3 kJ/mol 66.08231 ± 0.00030 13966-66-0*2 Silylene SiH2 (g, triplet) 361.96 360.34 ± 0.99 kJ/mol 30.10138 ± 0.00033 13825-90-6*1 Di-mu-hydrodihydrodisilicon HSi(HSiHH) (g, trans-singlet) 374.8 364.4 ± 2.3 kJ/mol 60.20276 ± 0.00066 129970-82-7*12 Trimethylsiloxy (CH3)3SiO (g) -188.1 -211.1 ± 1.9 kJ/mol 89.1885 ± 0.0025 54572-10-0*0 1,5-Hexadiyne HCCCH2CH2CCH (g) 431.7 421.2 ± 1.2 kJ/mol 78.1118 ± 0.0048 628-16-0*0 2-Methylallyl CH3C(CH2)CH2 (g) 155.97 138.85 ± 0.77 kJ/mol 55.0984 ± 0.0032 15157-95-6*0 3-Butenyl CH2CHCH2CH2 (g) 223.26 206.76 ± 0.90 kJ/mol 55.0984 ± 0.0032 2154-62-3*0 2-Methyl-1-propenyl CH3C(CH3)CH (g) 251.26 234.24 ± 0.72 kJ/mol 55.0984 ± 0.0032 33825-33-1*0 N-Methylethanamine CH3CH2NHCH3 (g) -17.4 -45.6 ± 1.1 kJ/mol 59.1103 ± 0.0025 624-78-2*0 Phenanthrene C6H4(C2H2(CC(C4H4))) (g) 232.01 203.20 ± 0.75 kJ/mol 178.2292 ± 0.0112 85-01-8*0 Disulfene oxide SSO (g) -50.61 -52.63 ± 0.43 kJ/mol 80.1314 ± 0.0120 20901-21-7*0 Sulfur hydroxide oxide OHS(O)(O)O (g, staggered) -474.5 -483.9 ± 1.6 kJ/mol 97.0715 ± 0.0061 12337-07-4*1 Ethanethiol CH3CH2SH (g) -28.74 -45.57 ± 0.38 kJ/mol 62.1350 ± 0.0062 75-08-1*0 Chloride Cl- (aq) -166.990 ± 0.023 kJ/mol 35.45325 ± 0.00090 16887-00-6*800 Dinitrogen tetraoxide O2NNO2 (g) 20.16 10.87 ± 0.14 kJ/mol 92.0111 ± 0.0012 10544-72-6*0 Azanylium [NH3]+ (g) 944.274 937.319 ± 0.029 kJ/mol 17.03001 ± 0.00022 19496-55-0*0 Difluoroamidogen NF2 (g) 36.24 33.66 ± 0.63 kJ/mol 52.003546 ± 0.000070 3744-07-8*0 Fluoroimidogen NF (g, triplet) 232.64 232.63 ± 0.80 kJ/mol 33.005143 ± 0.000070 13967-06-1*1 Iodine monobromide IBr (g) 49.727 40.780 ± 0.066 kJ/mol 206.8085 ± 0.0010 7789-33-5*0 Oxygen atom O (g, singlet) 436.665 438.523 ± 0.0021 kJ/mol 15.99940 ± 0.00030 17778-80-2*2 Methyliumylidene [CH]+ (g) 1619.749 1623.093 ± 0.041 kJ/mol 13.01809 ± 0.00080 24361-82-8*0 Ethylidyne CH3C (g, doublet) 508.65 504.95 ± 0.80 kJ/mol 27.0452 ± 0.0016 67624-57-1*1 Vinylidene anion [CCH2]- (g) 364.28 364.09 ± 0.31 kJ/mol 26.0378 ± 0.0016 66295-36-1*0 Trioxidanyl HOOO (g, trans) 25.36 23.38 ± 0.13 kJ/mol 49.00614 ± 0.00090 12500-78-6*1 Methanol cation [CH3OH]+ (g) 856.89 846.57 ± 0.32 kJ/mol 32.04131 ± 0.00090 12538-91-9*0 Hydroxymethylene HCOH (g, gauche triplet) 219.3 216.4 ± 1.1 kJ/mol 30.02598 ± 0.00087 19710-56-6*3 Aquacarbon H2OC (g, triplet) 442.7 441.1 ± 1.3 kJ/mol 30.02598 ± 0.00087 81434-73-3*1 Iodine I (g, 2P3/2) 107.157 106.757 ± 0.0021 kJ/mol 126.904470 ± 0.000030 14362-44-8*1 Carbonic acid C(O)(OH)2 (g, cis-trans) -596.43 -606.54 ± 0.73 kJ/mol 62.0248 ± 0.0012 463-79-6*2 Carbonic acid C(O)(OH)2 (g, trans-trans) -561.24 -570.09 ± 0.91 kJ/mol 62.0248 ± 0.0012 463-79-6*3 Trioxygen difluoride FOOOF (g, trans) 112.5 106.7 ± 1.1 kJ/mol 85.99501 ± 0.00090 16829-28-0*1 Hydroperoxycarbonyl HOOCO (g) -73.24 -77.10 ± 0.97 kJ/mol 61.0168 ± 0.0012 153751-35-0*0 1,3-Dioxolan-2-one C(O)(OCH2CH2O) (g) -492.60 -510.24 ± 0.85 kJ/mol 88.0621 ± 0.0026 96-49-1*0 Pyruvic acid CH3C(O)C(O)OH (g) -520.53 -534.87 ± 0.97 kJ/mol 88.0621 ± 0.0026 127-17-3*0 Dimethyl carbonate C(O)(OCH3)2 (g, cis-cis) -550.03 -570.58 ± 0.37 kJ/mol 90.0779 ± 0.0026 616-38-6*1 Allylium [CH2CHCH2]+ (g) 964.48 952.92 ± 0.33 kJ/mol 41.0713 ± 0.0024 1724-44-3*0 Propylidyne CH3CH2C (g, quartet) 625.0 613.4 ± 1.2 kJ/mol 41.0718 ± 0.0024 85056-54-8*2 1-Propynyl CH3CC (g) 528.57 526.40 ± 0.65 kJ/mol 39.0559 ± 0.0024 89342-91-6*0 1-Propynylide [CH3CC]- (g) 264.62 261.04 ± 0.66 kJ/mol 39.0565 ± 0.0024 36147-87-2*0 1-Propen-1-yl-3-ylidene CHCHCH (g, c-c quartet) 656.8 653.3 ± 1.1 kJ/mol 39.0559 ± 0.0024 84654-90-0*11 Oxidanylium [OH]+ (g) 1293.362 1293.391 ± 0.026 kJ/mol 17.00679 ± 0.00031 12259-29-9*0 t-Butyl anion [(CH3)3C]- (g) 76.9 52.1 ± 1.3 kJ/mol 57.1148 ± 0.0033 65114-21-8*0 Methylcyclopropane CH3CH(CH2CH2) (g) 47.5 24.2 ± 1.2 kJ/mol 56.1063 ± 0.0032 594-11-6*0 5-Ethenyl-1,3-cyclopentadiene CH2CHCH(CHCHCHCH) (g, perp) 237.2 215.4 ± 1.4 kJ/mol 92.1384 ± 0.0056 29647-85-6*1 2-Hydroxyethenyl CHCHOH (g, trans-cis) 138.01 131.27 ± 0.72 kJ/mol 43.0446 ± 0.0016 108665-16-3*21 Ethynol HCCOH (g, gauche triplet) 399.8 397.4 ± 1.8 kJ/mol 42.0367 ± 0.0016 32038-79-2*11 Oxiranylidene CH2(CO) (g, singlet) 213.5 209.3 ± 1.4 kJ/mol 42.0367 ± 0.0016 50983-85-2*2 1-Hydroperoxyethylium [CH3CHOOH]+ (g, trans singlet) 690.7 675.0 ± 1.5 kJ/mol 61.0594 ± 0.0017 *126898-98-4*21 Ethenyldioxy CH2CHOO (g, anti) 118.42 108.92 ± 0.99 kJ/mol 59.0440 ± 0.0017 88181-72-0*1 Hydroxyformyl anion [HOCO]- (g, trans) -313.63 -315.43 ± 0.56 kJ/mol 45.0180 ± 0.0010 78944-70-4*1 Ethoxyethene CH2CHOCH2CH3 (g, cis-trans) -117.7 -141.5 ± 1.5 kJ/mol 72.1057 ± 0.0033 109-92-2*2 1,1-Ethenediol CH2C(OH)2 (g, syn-anti Cs) -307.51 -320.46 ± 0.82 kJ/mol 60.0520 ± 0.0017 10375-04-9*1 1,2-Ethenediol HOCHCHOH (g, cis) -272.64 -284.97 ± 0.89 kJ/mol 60.0520 ± 0.0017 1571-60-4*1 1-Methoxyethenol CH2C(OH)OCH3 (g, anti-syn) -284.2 -303.6 ± 1.1 kJ/mol 74.0785 ± 0.0025 4453-91-2*1 Hydroxy(1-methylethylidene)oxonium CH3C(CH3)OO (g) 3.52 -15.46 ± 0.94 kJ/mol 74.0785 ± 0.0025 65339-02-8*0 (Formyloxy)methyl HC(O)OCH2 (g, syn) -151.3 -159.4 ± 1.1 kJ/mol 59.0440 ± 0.0017 3122-12-1*1 Ethylene glycol (CH2OH)2 (g) -369.65 -389.27 ± 0.40 kJ/mol 62.0678 ± 0.0018 107-21-1*0 Oxalic acid (C(O)OH)2 (g) -721.0 -731.6 ± 1.2 kJ/mol 90.0349 ± 0.0020 144-62-7*0 (Methylamino)methyl cation [CH3NHCH2]+ (g) 729.63 711.01 ± 0.97 kJ/mol 44.0752 ± 0.0017 *31277-24-4*0 (Methyleneamino)methyl anion [CH2NCH2]- (g) 187.0 176.6 ± 1.6 kJ/mol 42.0604 ± 0.0016 73859-26-4*0 2-Aminoethenyl CHCHNH2 (g, anti) 319.8 309.6 ± 1.3 kJ/mol 42.0599 ± 0.0016 176964-54-8*2 Bromochlorane BrCl (g) 21.891 14.447 ± 0.059 kJ/mol 115.3567 ± 0.0013 13863-41-7*0 Bromotrichloromethane CCl3Br (g) -29.81 -38.95 ± 0.53 kJ/mol 198.2728 ± 0.0030 75-62-7*0 Dichloromethyl CHCl2 (g) 92.91 90.99 ± 0.88 kJ/mol 83.9240 ± 0.0020 3474-12-2*0 Chloromethyl CH2Cl (g) 118.47 115.40 ± 0.87 kJ/mol 49.4793 ± 0.0012 6806-86-6*0 Methyl hypochlorite CH3OCl (g) -53.0 -63.0 ± 1.4 kJ/mol 66.4866 ± 0.0013 593-78-2*0 1,2-Dichloroethane CH2ClCH2Cl (g) -118.49 -130.44 ± 0.53 kJ/mol 98.9586 ± 0.0024 107-06-2*0 Chlorofluoromethane CH2FCl (g) -256.43 -263.63 ± 0.85 kJ/mol 68.4777 ± 0.0012 593-70-4*0 Difluoromethyliumyl [CF2]+ (g) 908.35 908.78 ± 0.77 kJ/mol 50.00696 ± 0.00080 54250-40-7*0 Fluoromethyliumylidene [CF]+ (g) 1123.49 1126.70 ± 0.37 kJ/mol 31.00855 ± 0.00080 33412-11-2*0 Hydrogen fluoride HF (aq, 5500 H2O) -324.55 ± 0.13 kJ/mol 20.006343 ± 0.000070 7664-39-3*955 1,2-Difluoroacetylene FCCF (g) 2.85 5.67 ± 0.63 kJ/mol 62.0182 ± 0.0016 689-99-6*0 Iodoacetylene HCCI (g) 324.0 323.8 ± 2.0 kJ/mol 151.9338 ± 0.0016 14545-08-5*0 Chloroformyl ClCO (g) -21.92 -20.53 ± 0.49 kJ/mol 63.4628 ± 0.0012 2602-42-8*0 o-Benzyne anion [C6H4]- (g) 413.87 404.76 ± 0.95 kJ/mol 76.0965 ± 0.0048 100569-88-8*0 Tetroxidane HOOOOH (g, C1) -33.32 -43.99 ± 0.44 kJ/mol 66.0135 ± 0.0012 29683-94-1*21 Dioxaziridinyl N(OO) (g) 355.1 352.6 ± 1.4 kJ/mol 46.00554 ± 0.00060 66252-29-7*0 Cycloheptene CH2(CHCHCH2CH2CH2CH2) (g) 28.58 -8.65 ± 0.74 kJ/mol 96.1702 ± 0.0057 628-92-2*0 Anisole C6H5OCH3 (g) -45.97 -70.81 ± 0.63 kJ/mol 108.1378 ± 0.0056 100-66-3*0 Benzoylium [C6H5CO]+ (g) 764.1 750.0 ± 1.3 kJ/mol 105.1135 ± 0.0056 19270-10-1*0 Benzoyl fluoride C6H5C(O)F (g) -287.9 -304.3 ± 1.3 kJ/mol 124.1124 ± 0.0056 455-32-3*0 Fluorobenzene cation [C6H5F]+ (g) 791.94 776.92 ± 0.39 kJ/mol 96.1018 ± 0.0048 34468-25-2*0 Nitrosobenzene C6H5NO (g) 217.0 200.0 ± 1.2 kJ/mol 107.1100 ± 0.0048 586-96-9*0 1-Methylethoxy CH3CH(O)CH3 (g) -25.05 -43.81 ± 0.74 kJ/mol 59.0871 ± 0.0025 3958-66-5*0 Nitromethyl CH2N(O)O (g) 139.8 130.4 ± 1.1 kJ/mol 60.0321 ± 0.0010 16787-85-2*0 Nitroethane CH3CH2N(O)O (g) -83.42 -102.75 ± 0.62 kJ/mol 75.0666 ± 0.0017 79-24-3*0 Carboxymethanaminium [NH3CH2C(O)OH]+ (g, syn-anti) 270.0 246.6 ± 1.1 kJ/mol 76.0740 ± 0.0018 *56-40-6*1 Hypochloroperoxoous acid, hydroxy ester HOOOCl (g, syn) 48.4 41.5 ± 1.8 kJ/mol 84.4588 ± 0.0013 928652-99-7*1 cis-1,2-Dibromoethene CHBrCHBr (g, cis) 124.7 104.1 ± 1.6 kJ/mol 185.8453 ± 0.0026 590-11-4*0 2-Butanone CH3CH2C(O)CH3 (g) -216.83 -238.28 ± 0.79 kJ/mol 72.1057 ± 0.0033 78-93-3*0 Acryloyl CH2CHCO (g, 2A', trans) 101.2 95.2 ± 1.4 kJ/mol 55.0553 ± 0.0024 72241-20-4*11 Formaldoxime CH2NOH (g, trans) 30.6 20.0 ± 1.3 kJ/mol 45.04066 ± 0.00088 75-17-2*1 1,3-Cyclobutadien-1-yl C(CHCHCH) (g) 653.9 649.4 ± 1.1 kJ/mol 51.0666 ± 0.0032 127611-22-7*0 5-Methyl-1,3-cyclopentadiene CH3CH(CHCHCHCH) (g) 134.1 111.1 ± 1.4 kJ/mol 80.1277 ± 0.0048 96-38-8*0 Trifluorosilyl SiF3 (g) -993.0 -996.0 ± 1.3 kJ/mol 85.08071 ± 0.00030 14835-14-4*0 Silylsilylene SiH3SiH (g, singlet) 317.3 309.5 ± 1.9 kJ/mol 60.20276 ± 0.00066 50420-90-1*2 Fluorotrimethylsilane SiF(CH3)3 (g) -547.1 -570.7 ± 2.0 kJ/mol 92.1875 ± 0.0025 420-56-4*0 Chlorotrimethylsilane SiCl(CH3)3 (g) -326.3 -349.4 ± 2.3 kJ/mol 108.6418 ± 0.0027 75-77-4*0 Trimethylsiloxide [(CH3)3SiO]- (g) -486.6 -510.4 ± 2.1 kJ/mol 89.1890 ± 0.0025 41866-81-3*0 1,4-Hexadiyne HCCCH2CCCH3 (g) 424.8 414.8 ± 1.2 kJ/mol 78.1118 ± 0.0048 10420-91-4*0 Biallenyl CH2CCHCHCCH2 (g, trans) 410.7 399.0 ± 1.5 kJ/mol 78.1118 ± 0.0048 29776-96-3*1 1,2,3,4-Hexatetraene CH2CCCCHCH3 (g) 429.9 420.1 ± 1.5 kJ/mol 78.1118 ± 0.0048 177856-38-1*0 Pentatetraene CH2CCCCH2 (g) 452.62 448.62 ± 0.93 kJ/mol 64.0853 ± 0.0040 21986-03-8*0 1-Aminoethyl CH3CHNH2 (g) 133.37 116.59 ± 0.93 kJ/mol 44.0758 ± 0.0017 30208-36-7*0 Ethylamidogen CH3CH2NH (g) 166.75 150.62 ± 0.94 kJ/mol 44.0758 ± 0.0017 41084-92-8*0 2-Naphthyl anion [C6H4(CHCCHCH)]- (g) 288.8 269.4 ± 1.2 kJ/mol 127.1631 ± 0.0080 88760-89-8*0 1-Naphthyl anion [C6H4(CCHCHCH)]- (g) 283.6 264.2 ± 1.2 kJ/mol 127.1631 ± 0.0080 125254-29-7*0 Nitrosamine NH2NO (g) 85.83 76.95 ± 0.95 kJ/mol 46.02876 ± 0.00036 35576-91-1*0 Sulfur trioxide anion [OS(O)O]- (g) -603.0 -608.6 ± 2.3 kJ/mol 80.0647 ± 0.0061 12210-38-7*0 Diazenyl NNH (g) 252.16 249.24 ± 0.45 kJ/mol 29.02142 ± 0.00016 36882-13-0*0 Nitrosyl chloride ClNO (g) 54.457 52.555 ± 0.066 kJ/mol 65.45884 ± 0.00095 2696-92-6*0 Carbide [C2]- (g) 504.39 510.97 ± 0.31 kJ/mol 24.0219 ± 0.0016 12595-78-7*0 Carbon dioxide CO2 (g, triplet) 49.8 50.6 ± 1.1 kJ/mol 44.00950 ± 0.00100 124-38-9*1 Bicyclo[1.1.0]buta-1,3-diene-2,4-diyl C(CC)C (g) 1047.14 1054.73 ± 0.68 kJ/mol 48.0428 ± 0.0032 12184-80-4*0 Methane cation [CH4]+ (g) 1150.689 1144.306 ± 0.057 kJ/mol 16.04191 ± 0.00085 20741-88-2*0 Ethanium [C2H7]+ (g) 874.39 858.15 ± 0.61 kJ/mol 31.0764 ± 0.0017 24669-33-8*0 Bifluoride [(HF)(F)]- (g, singlet) -481.8 -480.6 ± 1.9 kJ/mol 39.005295 ± 0.000070 *18130-74-0*2 Acetylene cation [HCCH]+ (g) 1328.91 1328.24 ± 0.12 kJ/mol 26.0367 ± 0.0016 25641-79-6*0 Chlorine difluoride FClF (g) -47.0 -48.2 ± 1.3 kJ/mol 73.44951 ± 0.00090 24801-48-7*0 1-Ethylium-1-ylidene [CH3C]+ (g) 1329.8 1328.3 ± 1.2 kJ/mol 27.0447 ± 0.0016 78949-84-5*0 Ethylidyne anion [CH3C]- (g) 457.2 453.1 ± 1.2 kJ/mol 27.0458 ± 0.0016 117768-70-4*0 Vinylidene CCH2 (g, triplet) 610.65 610.36 ± 0.39 kJ/mol 26.0373 ± 0.0016 2143-69-3*1 Bromide Br- (aq) -120.50 ± 0.12 kJ/mol 79.90455 ± 0.00100 24959-67-9*800 Dinitrogen pentoxide O2NONO2 (g) 24.31 14.74 ± 0.29 kJ/mol 108.0105 ± 0.0015 10102-03-1*0 Hydrogen fluoride HF (aq) -334.67 ± 0.15 kJ/mol 20.006343 ± 0.000070 7664-39-3*800 Water anion [(H)(OH)]- (g, vdW ?) 31.3 29.8 ± 3.1 kJ/mol 18.01583 ± 0.00033 12259-30-2*100 Isocyanomethyl CH2NC (g) 363.3 360.8 ± 1.1 kJ/mol 40.0440 ± 0.0016 70971-59-4*0 Methyloxoniumylidene [CH3O]+ (g) 1062.72 1054.91 ± 0.57 kJ/mol 31.03337 ± 0.00088 58157-09-8*0 Hydroxymethanide [CH2OH]- (g) 10.0 3.4 ± 1.5 kJ/mol 31.03447 ± 0.00088 55830-71-2*0 Formaldehyde CH2O (g, singlet) -105.380 -109.220 ± 0.094 kJ/mol 30.02598 ± 0.00087 50-00-0*2 Hydroxymethylene HCOH (g, cis) 131.12 127.37 ± 0.29 kJ/mol 30.02598 ± 0.00087 19710-56-6*2 Hydroxymethylene cation [HCOH]+ (g, trans) 971.9 968.2 ± 1.4 kJ/mol 30.02543 ± 0.00087 135395-06-1*1 Isoformyl COH (g) 217.25 217.64 ± 0.69 kJ/mol 29.01804 ± 0.00086 71080-92-7*0 Hydroxyoxomethoxy HOC(O)O (g) -360.34 -366.41 ± 0.93 kJ/mol 61.0168 ± 0.0012 38330-85-7*0 3-Dioxiranone OC(OO) (g) -159.9 -162.7 ± 1.5 kJ/mol 60.0089 ± 0.0012 94660-13-6*0 Carbonylbis(oxy) anion [OC(O)O]- (g) -550.4 -552.4 ± 1.4 kJ/mol 60.0094 ± 0.0012 16518-46-0*0 Methyl hydrocarbonate C(O)(OH)OCH3 (g, cis-cis) -576.99 -592.55 ± 0.87 kJ/mol 76.0514 ± 0.0019 7456-87-3*1 1,2,3-Trioxolane O(OCH2CH2O) (g) -5.6 -23.3 ± 1.5 kJ/mol 76.0514 ± 0.0019 6669-36-9*0 1-Methylethylidene CH3CCH3 (g, triplet) 326.9 313.8 ± 1.2 kJ/mol 42.0797 ± 0.0024 40852-89-9*1 1-Propenyl CH3CHCH (g, trans) 280.27 269.45 ± 0.76 kJ/mol 41.0718 ± 0.0024 6067-68-1*1 Cyclopropynyl CH(CC) (g) 711.28 715.40 ± 0.71 kJ/mol 37.0400 ± 0.0024 119178-99-3*0 n-Butyl anion [CH3CH2CH2CH2]- (g) 106.2 81.3 ± 1.3 kJ/mol 57.1148 ± 0.0033 79431-01-9*0 sec-Butyl anion [CH3CH2CHCH3]- (g) 103.4 78.9 ± 1.3 kJ/mol 57.1148 ± 0.0033 79431-00-8*0 1,2-Butadienyl anion [CH3CHCCH]- (g) 255.7 246.2 ± 1.1 kJ/mol 53.0830 ± 0.0032 65114-67-2*0 Neopentyl (CH3)3CCH2 (g) 70.0 40.3 ± 1.3 kJ/mol 71.1408 ± 0.0041 3744-21-6*0 Trioxidanylium [HOOO]+ (g, trans) 1070.7 1064.4 ± 1.4 kJ/mol 49.00559 ± 0.00090 74241-49-9*1 n-Hexane CH3CH2CH2CH2CH2CH3 (cr,l) -179.82 -198.48 ± 0.32 kJ/mol 86.1754 ± 0.0049 110-54-3*500 n-Nonane CH3(CH2)7CH3 (g) -176.26 -228.04 ± 0.48 kJ/mol 128.2551 ± 0.0073 111-84-2*0 1-Hydroxyethylium [CH3CHOH]+ (g, syn) 611.0 596.5 ± 1.1 kJ/mol 45.0600 ± 0.0017 18682-96-7*2 2-Hydroxyethyl CH2CH2OH (g, gauche-anti) -10.83 -23.46 ± 0.93 kJ/mol 45.0605 ± 0.0017 4422-54-2*2 Ethoxy CH3CH2O (g) 1.39 -12.03 ± 0.42 kJ/mol 45.0605 ± 0.0017 2154-50-9*0 Vinyl alcohol cation [CH2CHOH]+ (g, anti) 778.7 767.4 ± 1.3 kJ/mol 44.0520 ± 0.0017 57239-63-1*2 1-Hydroxyethylidene CH3COH (g, syn singlet) 70.08 59.57 ± 0.86 kJ/mol 44.0526 ± 0.0017 30967-49-8*22 1-Hydroxyethenyl CH2COH (g) 121.32 114.94 ± 0.83 kJ/mol 43.0446 ± 0.0016 81847-74-7*0 Oxiranylium [CH2(CHO)]+ (g, singlet) 901.3 893.3 ± 1.4 kJ/mol 43.0441 ± 0.0016 57789-76-1*2 C=O=C COC (g, triplet) 653.0 657.3 ± 1.5 kJ/mol 40.0208 ± 0.0016 *12071-23-7*1 C=O=C COC (g, singlet) 721.9 726.2 ± 1.6 kJ/mol 40.0208 ± 0.0016 *12071-23-7*2 Oxoethylidene HCC(O)H (g, singlet) 275.4 272.6 ± 1.7 kJ/mol 42.0367 ± 0.0016 39920-84-8*2 Iodide I- (aq) -56.824 ± 0.090 kJ/mol 126.905019 ± 0.000030 20461-54-5*800 Dihydroxymethanide [CH(OH)2]- (g, syn-syn) -194.2 -203.2 ± 1.8 kJ/mol 47.0339 ± 0.0010 61192-32-3*2 1-Hydroperoxyethyl CH3CHOOH (g) 39.7 26.1 ± 1.3 kJ/mol 61.0599 ± 0.0017 126898-98-4*0 Formic acid cation [HC(O)OH]+ (g, syn) 722.00 714.91 ± 0.24 kJ/mol 46.0248 ± 0.0010 50614-05-6*1 Methyldioxirane CH3CH(OO) (g) -40.45 -54.37 ± 0.91 kJ/mol 60.0520 ± 0.0017 70308-85-9*0 Formyloxidanyl HC(O)O (g, 2B2) -121.95 -125.30 ± 0.55 kJ/mol 45.0174 ± 0.0010 16499-21-1*2 Hydrogen bromide HBr (aq) -120.50 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*800 1-Propene-1,2-diol CH3C(OH)CHOH (g, cis) -311.3 -329.7 ± 1.2 kJ/mol 74.0785 ± 0.0025 7333-03-1*1 1-Propene-1,2-diol CH3C(OH)CHOH (g, trans) -293.1 -309.7 ± 1.2 kJ/mol 74.0785 ± 0.0025 7333-03-1*2 1-Methylethenyl hydroperoxide CH2C(CH3)OOH (g, anti-perp) -63.4 -82.0 ± 1.3 kJ/mol 74.0785 ± 0.0025 177944-34-2*1 (Formyloxy)methyl HC(O)OCH2 (g, anti) -135.7 -143.8 ± 1.3 kJ/mol 59.0440 ± 0.0017 3122-12-1*2 Carboxymethyl CH2C(O)OH (g, anti) -205.9 -215.3 ± 1.2 kJ/mol 59.0440 ± 0.0017 2887-46-9*2 Dimethylamide [(CH3)2N]- (g) 123.1 104.7 ± 1.4 kJ/mol 44.0763 ± 0.0017 34285-60-4*0 Ethylideneamidogen CH3CHN (g) 209.8 199.3 ± 1.1 kJ/mol 42.0599 ± 0.0016 28445-33-2*0 (Methyleneamino)methyl CH2NCH2 (g) 244.3 233.6 ± 1.3 kJ/mol 42.0599 ± 0.0016 56391-78-7*0 Azide [NNN]- (g) 193.63 190.12 ± 0.91 kJ/mol 42.02077 ± 0.00021 14343-69-2*0 2-Aminoethenyl CHCHNH2 (g, syn) 325.6 315.4 ± 1.3 kJ/mol 42.0599 ± 0.0016 176964-54-8*1 Bromo hypobromite BrOBr (g) 121.1 104.6 ± 1.2 kJ/mol 175.8074 ± 0.0020 21308-80-5*0 2-Aziridinyl NH(CHCH2) (g, syn) 361.0 348.8 ± 1.7 kJ/mol 42.0599 ± 0.0016 *23838-09-7*1 Diazirenide [HC(NN)]- (g, singlet) 454.9 452.2 ± 1.5 kJ/mol 41.03267 ± 0.00082 130614-84-5*2 1H-Diazirin-3-yl HN(NC) (g, doublet) 618.7 615.8 ± 1.6 kJ/mol 41.03212 ± 0.00082 324529-57-9*1 1H-Triazirin-1-yl N(NN) (g) 586.0 584.2 ± 2.0 kJ/mol 42.02022 ± 0.00021 912535-95-6*0 1H-Diazirene CH(NHN) (g) 405.1 398.1 ± 1.4 kJ/mol 42.04006 ± 0.00082 157-23-3*0 Dioxidenium [HOO]+ (g) 1110.87 1107.98 ± 0.11 kJ/mol 33.00619 ± 0.00060 12207-52-2*0 1,1,2-Trichloroethane CH2ClCHCl2 (g) -135.6 -147.3 ± 1.1 kJ/mol 133.4033 ± 0.0031 79-00-5*0 1,1,1,2-Tetrachloroethane CH2ClCCl3 (g) -144.4 -152.9 ± 1.3 kJ/mol 167.8481 ± 0.0039 630-20-6*0 Pentachloroethyl CCl3CCl2 (g) 28.9 27.1 ± 1.3 kJ/mol 201.2849 ± 0.0048 7094-17-9*0 Iodomethane CH3I (l) -12.15 ± 0.18 kJ/mol 141.93899 ± 0.00083 74-88-4*590 Difluoromethylene CF2 (g, triplet) 43.30 44.02 ± 0.35 kJ/mol 50.00751 ± 0.00080 2154-59-8*1 Ethyl iodide CH3CH2I (l) -9.40 -39.27 ± 0.48 kJ/mol 155.9656 ± 0.0016 75-03-6*500 cis-1,2-Difluoroethene CHFCHF (g, cis) -302.96 -309.72 ± 0.83 kJ/mol 64.0341 ± 0.0016 1630-77-9*0 Fluoroethynyl CCF (g) 445.3 449.9 ± 1.6 kJ/mol 43.0198 ± 0.0016 22533-50-2*0 Fluoro(fluorooxy)methylene FCOF (g, cis) -134.8 -136.0 ± 1.3 kJ/mol 66.00691 ± 0.00085 479587-30-9*2 Dibromophosgene CBr2O (g) -97.93 -113.86 ± 0.37 kJ/mol 187.8181 ± 0.0022 593-95-3*0 1,3,5-Hexatriynyl CCCCCCH (g) 1003.2 1010.6 ± 2.3 kJ/mol 73.0721 ± 0.0048 88053-50-3*0 Chloryl hydride HCl(O)O (g) 197.7 191.2 ± 1.6 kJ/mol 68.4594 ± 0.0011 174365-32-3*0 Benzene C6H6 (cr,l) 50.79 49.25 ± 0.21 kJ/mol 78.1118 ± 0.0048 71-43-2*500 o-Benzyne C6H4 (g) 468.25 459.33 ± 0.86 kJ/mol 76.0960 ± 0.0048 462-80-6*0 m-Benzyne C6H4 (g, singlet) 527.5 519.0 ± 1.2 kJ/mol 76.0960 ± 0.0048 1828-89-3*2 p-Benzyne C6H4 (g, singlet) 587.1 577.6 ± 1.2 kJ/mol 76.0960 ± 0.0048 3355-34-8*2 Cycloheptane CH2(CH2CH2CH2CH2CH2CH2) (g) -72.39 -117.89 ± 0.52 kJ/mol 98.1861 ± 0.0057 291-64-5*0 Hydrogen difluoride (F)(HF) (g, lin) -198.5 -198.4 ± 1.2 kJ/mol 39.004746 ± 0.000070 12528-21-1*1 1-Oxopropyl CH3CH2CO (g, gauche) -17.32 -29.81 ± 0.93 kJ/mol 57.0712 ± 0.0024 15843-24-0*2 Propyn-1-ol CH3CCOH (g) 65.7 57.4 ± 1.1 kJ/mol 56.0633 ± 0.0024 6175-54-8*0 Formylethynyl CCCHO (g) 468.5 470.4 ± 1.3 kJ/mol 53.0394 ± 0.0024 277743-00-7*0 2-Cyclopropen-1-one OC(CHCH) (g) 164.0 160.1 ± 1.1 kJ/mol 54.0474 ± 0.0024 2961-80-0*0 Formamide enol NHCHOH (g, anti-syn) -130.6 -141.8 ± 1.3 kJ/mol 45.04066 ± 0.00088 60100-09-6*1 Cyanovinylidene CCHCN (g) 581.8 584.3 ± 1.2 kJ/mol 51.0468 ± 0.0024 70277-81-5*0 Isocyanovinylidene CCHNC (g) 697.1 700.4 ± 1.4 kJ/mol 51.0468 ± 0.0024 737788-76-0*0 Isocyanoethene CH2CHNC (g, singlet) 285.32 278.82 ± 0.92 kJ/mol 53.0627 ± 0.0024 14668-82-7*1 1-Cyanoethylidene CH3CCN (g, triplet) 437.6 433.8 ± 1.4 kJ/mol 53.0627 ± 0.0024 498544-34-6*1 Isocyanomethylene HCNC (g, singlet) 583.1 584.4 ± 1.6 kJ/mol 39.0361 ± 0.0016 78694-65-2*1 2-Methyl-2-cyclopropen-1-ylidene CH3C(CHC) (g, singlet) 448.1 441.9 ± 1.2 kJ/mol 52.0746 ± 0.0032 185841-59-2*2 1,2,3-Butatrien-1-ylium [CH2CCCH]+ (g, triplet) 1425.9 1426.2 ± 1.3 kJ/mol 51.0661 ± 0.0032 81932-79-8*1 But-1-en-3-yn-1-ide [HCCCHCH]- (g, cis) 419.9 418.7 ± 1.2 kJ/mol 51.0672 ± 0.0032 119611-65-3*2 But-3-en-1-yn-1-ide [CH2CHCC]- (g, singlet) 326.8 323.7 ± 1.3 kJ/mol 51.0672 ± 0.0032 58870-47-6*2 Cyclobutenyl CH2(CHCHCH) (g) 337.3 324.8 ± 1.2 kJ/mol 53.0825 ± 0.0032 24669-29-2*0 Propargyl chloride HCCCH2Cl (g) 186.7 180.8 ± 1.3 kJ/mol 74.5086 ± 0.0026 624-65-7*0 Dioxosilane SiO2 (g) -277.9 -279.3 ± 2.0 kJ/mol 60.08430 ± 0.00067 7631-86-9*0 Dimethylsilane CH3SiH2CH3 (g) -66.7 -88.2 ± 1.1 kJ/mol 60.1704 ± 0.0017 1111-74-6*0 Trimethylsilyl Si(CH3)3 (g) 47.5 25.5 ± 1.9 kJ/mol 73.1891 ± 0.0025 16571-41-8*0 Benzvalene ((CHCH)(CH(CHCH)CH)) (g) 404.5 386.7 ± 1.2 kJ/mol 78.1118 ± 0.0048 659-85-8*0 1-Ethynyl-2-propyn-1-ylidene HCCCCCH (g, triplet) 727.1 734.1 ± 1.7 kJ/mol 62.0694 ± 0.0040 882068-94-2*1 1,2-Pentadien-4-yne HCCCHCCH2 (g) 442.32 436.69 ± 0.97 kJ/mol 64.0853 ± 0.0040 33555-85-0*0 2,4-Pentadiynyl HCCCCCH2 (g) 568.83 568.08 ± 0.98 kJ/mol 63.0773 ± 0.0040 115236-82-3*0 Bromonium [HBrH]+ (g) 924.4 913.6 ± 3.0 kJ/mol 81.9193 ± 0.0010 36658-54-5*0 2-Naphthalenyl C6H4(CHCCHCH) (g) 416.9 397.3 ± 1.3 kJ/mol 127.1626 ± 0.0080 10237-50-0*0 1-Naphthalenyl C6H4(CCHCHCH) (g) 418.2 398.6 ± 1.3 kJ/mol 127.1626 ± 0.0080 2510-51-2*0 Aniline C6H5NH2 (g) 108.83 86.82 ± 0.72 kJ/mol 93.1265 ± 0.0048 62-53-3*0 Thiodioxy SOO (g) 199.2 197.1 ± 1.3 kJ/mol 64.0648 ± 0.0060 164034-62-2*0 Sulfenic acid HSOH (g) -108.0 -114.2 ± 1.1 kJ/mol 50.0813 ± 0.0060 62607-44-7*0 3,3-Dioxidedioxathiirane OS(OO)O (g, singlet C2v) -257.1 -265.2 ± 1.4 kJ/mol 96.0636 ± 0.0061 1177730-84-5*2 Sulfate [OS(O)(O)O]-2 (g) -599.7 -608.4 ± 1.8 kJ/mol 96.0647 ± 0.0061 14808-79-8*0 Difluoroaminylium [NF2]+ (g, singlet) 1157.82 1154.93 ± 0.71 kJ/mol 52.002998 ± 0.000070 31685-31-1*2 (Z)-Difluorodiazene FNNF (g, cis) 78.5 72.9 ± 2.1 kJ/mol 66.01029 ± 0.00014 13812-43-6*2 (E)-Difluorodiazene FNNF (g, trans) 84.2 78.9 ± 2.3 kJ/mol 66.01029 ± 0.00014 13776-62-0*1 Dioxiranylidene C(OO) (g) 190.3 191.1 ± 1.4 kJ/mol 44.00950 ± 0.00100 138832-57-2*0 Bifluoride [FFH]- (g, triplet) -68.0 -67.6 ± 1.6 kJ/mol 39.005295 ± 0.000070 *18130-74-0*1 Aminomethylene CHNH2 (g) 245.9 238.1 ± 1.5 kJ/mol 29.04126 ± 0.00083 35430-17-2*0 Chlorine chlorite ClOClO (g, gauche) 168.6 166.2 ± 1.3 kJ/mol 102.9042 ± 0.0019 105206-44-8*3 Methyleneamidogen anion [CH2N]- (g) 192.85 189.09 ± 0.88 kJ/mol 28.03387 ± 0.00082 28892-56-0*0 (Z)-Iminomethyl HCNH (g, cis) 294.53 291.04 ± 0.89 kJ/mol 28.03332 ± 0.00082 54980-11-9*0 Aminomethylidyne CNH2 (g) 371.9 368.4 ± 1.1 kJ/mol 28.03332 ± 0.00082 84654-89-7*0 Oxofluoronium [FO]+ (g) 1342.66 1342.61 ± 0.80 kJ/mol 34.99725 ± 0.00030 12763-67-6*0 (E)-Diazene cation [HNNH]+ (g, trans) 1132.53 1125.59 ± 0.64 kJ/mol 30.02881 ± 0.00020 59952-06-6*0 Ethynylamidogen HCCNH (g) 395.32 393.29 ± 0.96 kJ/mol 40.0440 ± 0.0016 73456-14-1*0 Methyleneoxonium CH2OH2 (g) 152.51 144.19 ± 0.49 kJ/mol 32.04186 ± 0.00090 177788-17-9*0 (Z)-Diazene HNNH (g, cis) 228.80 221.67 ± 0.59 kJ/mol 30.02936 ± 0.00020 15626-42-3*0 Hydroxymethylene anion [HCOH]- (g, trans) 147.2 144.1 ± 1.6 kJ/mol 30.02653 ± 0.00087 207914-87-2*1 Hydroxymethyliumylidene [COH]+ (g) 986.01 987.65 ± 0.83 kJ/mol 29.01749 ± 0.00086 60528-75-8*0 Isoformyl anion [(CO)(H)]- (g, vdW singlet ?) 55.7 58.4 ± 1.8 kJ/mol 29.01859 ± 0.00086 81747-63-9*1 Carbonic acid C(O)(OH)2 (g) -602.24 -611.56 ± 0.55 kJ/mol 62.0248 ± 0.0012 463-79-6*0 Peroxyformic acid HC(O)OOH (g, trans) -265.2 -273.2 ± 1.5 kJ/mol 62.0248 ± 0.0012 107-32-4*2 Oxygen cation monohydrate [(HOH)O]+ (g) 1153.4 1147.9 ± 3.3 kJ/mol 34.01413 ± 0.00062 *31748-17-1*0 1,3-Propanediyl CH2CH2CH2 (g, triplet Cs) 319.3 307.1 ± 1.3 kJ/mol 42.0797 ± 0.0024 32458-33-6*11 Hydrogen difluoride cation [FFH]+ (g) 1174.3 1171.3 ± 1.5 kJ/mol 39.004198 ± 0.000070 *126950-54-7*0 Propan-1-yl-3-ylidene CH2CH2CH (g, quartet) 554.5 545.8 ± 1.3 kJ/mol 41.0718 ± 0.0024 *50457-59-5*2 1-Propenylidene CH3CHC (g, singlet) 392.5 388.1 ± 1.1 kJ/mol 40.0639 ± 0.0024 70277-78-0*1 Chlorine difluoride cation [FClF]+ (g) 998.9 996.7 ± 1.7 kJ/mol 73.44896 ± 0.00090 32629-46-2*0 Cycloprop-2-enyl CH(CHCH) (g) 490.35 485.80 ± 0.58 kJ/mol 39.0559 ± 0.0024 28933-84-8*0 2-Propen-1-yl-3-ylidene CH2CHC (g) 556.68 554.42 ± 0.89 kJ/mol 39.0559 ± 0.0024 202744-74-9*0 Fluoride F- (aq) -334.67 ± 0.15 kJ/mol 18.99895178 ± 0.00000050 16984-48-8*800 2-Propynylidyne anion [CCCH]- (g) 540.80 545.57 ± 0.75 kJ/mol 37.0406 ± 0.0024 82893-67-2*0 Deuterium atom D (g) 219.804 221.717 ± 0.000 kJ/mol 2.01410177800 ± 0.00000000040 16873-17-9*0 t-Butylium [(CH3)3C]+ (g) 733.97 710.69 ± 0.98 kJ/mol 57.1137 ± 0.0033 14804-25-2*0 Dioxosilane SiO2 (cr, quartz) -906.77 -911.75 ± 0.63 kJ/mol 60.08430 ± 0.00067 7631-86-9*505 1,2-Butadienylium [CH3CHCCH]+ (g, singlet) 1099.2 1089.9 ± 1.2 kJ/mol 53.0820 ± 0.0032 *65114-67-2*2 2-Hydroxy-1,1-dimethylethyl (CH3)2CCH2OH (g) -71.6 -96.5 ± 1.4 kJ/mol 73.1137 ± 0.0033 5723-75-1*0 Vinylcyclopentadienyl CH2CHC(CHCHCHCH) (g) 314.9 296.9 ± 1.7 kJ/mol 91.1305 ± 0.0056 1201826-88-1*0 2,2-Dimethylbutane CH3CH2C(CH3)3 (g) -145.27 -185.70 ± 0.75 kJ/mol 86.1754 ± 0.0049 75-83-2*0 n-Decane CH3(CH2)8CH3 (g) -192.28 -249.03 ± 0.75 kJ/mol 142.2817 ± 0.0081 124-18-5*0 Ethanol CH3CH2OH (cr,l) -269.59 -277.35 ± 0.20 kJ/mol 46.0684 ± 0.0017 64-17-5*500 Hydroxyaminiumyl [NOH]+ (g) 1161.1 1158.2 ± 1.4 kJ/mol 31.01353 ± 0.00032 63559-88-6*0 Vinyl alcohol cation [CH2CHOH]+ (g, syn) 786.66 775.44 ± 0.80 kJ/mol 44.0520 ± 0.0017 57239-63-1*1 Vinoxy cation [CH2CHO]+ (g, triplet) 1020.2 1013.2 ± 1.5 kJ/mol 43.0441 ± 0.0016 *35731-40-9*1 Vinoxide [CH2CHO]- (g) -153.08 -160.14 ± 0.53 kJ/mol 43.0452 ± 0.0016 35731-40-9*0 1-Hydroxyethenylium [CH2COH]+ (g, singlet) 841.7 834.9 ± 1.4 kJ/mol 43.0441 ± 0.0016 41084-89-3*2 Oxiranyl anion [CH2(CHO)]- (g, singlet) 121.2 113.2 ± 1.5 kJ/mol 43.0452 ± 0.0016 72722-59-9*2 COC vdW (CO)(C) (g, triplet) 589.7 598.5 ± 1.5 kJ/mol 40.0208 ± 0.0016 *12071-24-8*1 Oxirene O(CHCH) (g, c-triplet) 389.7 385.6 ± 1.4 kJ/mol 42.0367 ± 0.0016 157-18-6*12 Oxywater (H2O)O (g) 64.9 58.4 ± 1.3 kJ/mol 34.01468 ± 0.00062 171363-09-0*0 Hydroxyamidogen HNOH (g, cis) 123.3 116.7 ± 1.7 kJ/mol 32.02202 ± 0.00034 13940-32-4*2 Methanediol CH2(OH)2 (g, Cs gauche) -368.88 -381.82 ± 0.74 kJ/mol 48.0413 ± 0.0010 463-57-0*2 Hydroxyaminylium [HNOH]+ (g, trans) 1019.5 1012.3 ± 2.5 kJ/mol 32.02147 ± 0.00034 66097-71-0*1 Hydroxymethoxy anion [CH2(OH)O]- (g, syn) -373.82 -383.76 ± 0.85 kJ/mol 47.0339 ± 0.0010 67899-36-9*2 Ethoxyoxoniumylidene [CH3CH2OO]+ (g, triplet) 923.9 911.6 ± 1.5 kJ/mol 61.0594 ± 0.0017 268728-77-4*1 Ethaneperoxolate [CH3CH2OO]- (g, gauche) -120.32 -136.93 ± 0.68 kJ/mol 61.0604 ± 0.0017 268728-75-2*3 Triiodide [I3]- (aq) -51.53 ± 0.79 kJ/mol 380.713959 ± 0.000090 14900-04-0*800 Chlorosyl hydride HClO (g) 141.9 139.0 ± 1.7 kJ/mol 52.46004 ± 0.00095 71572-35-5*0 Formyloxoniumylidene [HC(O)O]+ (g) 1017.4 1014.0 ± 1.4 kJ/mol 45.0169 ± 0.0010 54375-27-8*0 Dioxymethylene HCOO (g, trans) 364.0 361.7 ± 2.4 kJ/mol 45.0174 ± 0.0010 438586-67-5*1 Aquachlorine cation [ClOH2]+ (g) 821.9 815.1 ± 1.8 kJ/mol 53.46743 ± 0.00096 142599-65-3*0 Cyanate [NCO]- (g) -221.16 -221.38 ± 0.53 kJ/mol 42.01739 ± 0.00086 661-20-1*0 Oxazirinyl C(NO) (g) 450.1 450.9 ± 1.5 kJ/mol 42.01684 ± 0.00086 228850-18-8*0 2-Propene-1,2-diol CH2C(OH)CH2OH (g, anti-gauche-gauche) -295.3 -314.8 ± 1.2 kJ/mol 74.0785 ± 0.0025 44169-27-9*11 2-Methoxy-2-oxoethyl CH2C(O)OCH3 (g, syn) -202.9 -218.1 ± 1.5 kJ/mol 73.0706 ± 0.0025 54668-31-4*1 (Acetyloxy)methyl CH3C(O)OCH2 (g, syn) -200.1 -213.8 ± 1.5 kJ/mol 73.0706 ± 0.0025 2887-49-2*1 Glyoxal OCHCHO (g) -207.82 -213.38 ± 0.54 kJ/mol 58.0361 ± 0.0017 107-22-2*0 2-Hydrotrioxy cation [OO(H)O]+ (g) 1298.4 1291.8 ± 1.4 kJ/mol 49.00559 ± 0.00090 *74241-49-9*0 Dimethylmethyleneammonium [(CH3)2NCH2]+ (g) 697.1 672.1 ± 1.3 kJ/mol 58.1018 ± 0.0025 28149-27-1*0 2-Methanidylidynehydrazin-2-ium-1-ide [HNNC]- (g, singlet) 281.9 279.1 ± 1.4 kJ/mol 41.03267 ± 0.00082 *947408-74-4*2 2-Methanidylidynehydrazin-2-ium-1-ide [HNNC]- (g, c-triplet) 518.6 516.1 ± 1.6 kJ/mol 41.03267 ± 0.00082 *947408-74-4*12 Isocyanamide NH2NC (g) 328.5 322.6 ± 1.5 kJ/mol 42.04006 ± 0.00082 4702-38-9*0 Dioxyamidogen HNOO (g, cis) 240.4 233.8 ± 1.8 kJ/mol 47.01348 ± 0.00061 71843-95-3*2 Trichloromethide [CCl3]- (g) -123.2 -122.6 ± 2.0 kJ/mol 118.3693 ± 0.0028 14478-07-0*0 2-Hydrotrioxy anion [OO(H)O]- (g) 27.4 21.6 ± 1.4 kJ/mol 49.00669 ± 0.00090 *89965-38-8*0 1,1,2,2-Tetrachloroethane CHCl2CHCl2 (g) -146.7 -156.1 ± 1.5 kJ/mol 167.8481 ± 0.0039 79-34-5*0 1,1,2,2-Tetrachloroethane CHCl2CHCl2 (cr,l) -172.8 -201.8 ± 1.5 kJ/mol 167.8481 ± 0.0039 79-34-5*500 Pentachloroethane CHCl2CCl3 (cr,l) -201.9 ± 2.5 kJ/mol 202.2928 ± 0.0048 76-01-7*500 Trichloroethene CHClCCl2 (l) -48.7 ± 1.5 kJ/mol 131.3874 ± 0.0031 79-01-6*590 Tetrachloroethene CCl2CCl2 (l) -61.10 ± 0.99 kJ/mol 165.8322 ± 0.0039 127-18-4*500 Trichloroethene CHClCCl2 (g) -10.9 -14.1 ± 1.5 kJ/mol 131.3874 ± 0.0031 79-01-6*0 Bromodichloromethane CHCl2Br (g) -34.8 -46.5 ± 1.2 kJ/mol 163.8280 ± 0.0022 75-27-4*0 Diiodomethane CH2I2 (g) 122.96 113.52 ± 0.78 kJ/mol 267.83552 ± 0.00081 75-11-6*0 Difluorodibromomethane CF2Br2 (g) -359.8 -377.8 ± 1.3 kJ/mol 209.8155 ± 0.0022 75-61-6*0 Dichlorodibromomethane CCl2Br2 (g) 28.3 12.4 ± 1.2 kJ/mol 242.7241 ± 0.0028 594-18-3*0 Difluorobromomethane CHF2Br (g) -411.40 -424.59 ± 0.47 kJ/mol 130.9194 ± 0.0013 1511-62-2*0 1,2-Difluoroethane CH2FCH2F (g) -434.39 -447.81 ± 0.80 kJ/mol 66.0500 ± 0.0016 624-72-6*0 Fluoro(fluorooxy)methylene FCOF (g, trans) -37.5 -39.1 ± 1.4 kJ/mol 66.00691 ± 0.00085 479587-30-9*1 Benzenium [CH2(CHCHCHCHCH)]+ (g) 887.8 867.7 ± 1.1 kJ/mol 79.1192 ± 0.0048 26812-57-7*0 Phenylium [C6H5]+ (g, triplet) 1251.3 1238.2 ± 1.6 kJ/mol 77.1034 ± 0.0048 17333-73-2*1 Benzylium [C6H5CH2]+ (g) 929.58 910.09 ± 0.51 kJ/mol 91.1299 ± 0.0056 6711-19-9*0 Benzylidene C6H5CH (g, triplet) 473.0 457.7 ± 1.3 kJ/mol 90.1225 ± 0.0056 3101-08-4*1 Cycloheptatetraene C(CHCHCHCHCHCH) (g, singlet) 418.8 403.1 ± 1.3 kJ/mol 90.1225 ± 0.0056 52783-93-4*2 2,5-Norbornadien-7-yl (CHCH)(CHCHCH)(CHCH) (g) 480.2 459.2 ± 1.7 kJ/mol 91.1305 ± 0.0056 35430-15-0*0 Pentalene CH(CHC(CHCHCH)CCH) (g) 389.9 373.6 ± 1.4 kJ/mol 102.1332 ± 0.0064 250-25-9*0 Dihydrogen fluoride anion [HFH]- (g, triplet) 133.2 131.9 ± 1.6 kJ/mol 21.01483 ± 0.00014 117339-92-1*1 Indenyl C6H4(CHCHCH) (g) 299.2 279.2 ± 1.6 kJ/mol 115.1519 ± 0.0072 71551-80-9*0 Benzoyl chloride C6H5C(O)Cl (cr,l) -157.10 ± 0.26 kJ/mol 140.5667 ± 0.0057 98-88-4*500 Benzoyl chloride C6H5C(O)Cl (g) -89.5 -104.8 ± 1.2 kJ/mol 140.5667 ± 0.0057 98-88-4*0 Hexafluorobenzene C6F6 (g) -942.55 -947.55 ± 0.87 kJ/mol 186.0546 ± 0.0048 392-56-3*0 Chlorobenzene cation [C6H5Cl]+ (g) 942.61 928.68 ± 0.61 kJ/mol 112.5561 ± 0.0049 55450-32-3*0 Chlorobenzene C6H5Cl (cr,l) 11.36 ± 0.59 kJ/mol 112.5566 ± 0.0049 108-90-7*500 m-Chlorophenyl C6H4Cl (g) 321.8 311.0 ± 1.6 kJ/mol 111.5487 ± 0.0049 3474-40-6*0 p-Chlorophenyl C6H4Cl (g) 324.7 313.9 ± 1.6 kJ/mol 111.5487 ± 0.0049 2396-00-1*0 o-Chlorophenyl C6H4Cl (g) 328.9 318.2 ± 1.6 kJ/mol 111.5487 ± 0.0049 3474-42-8*0 Bromobenzene cation [C6H5Br]+ (g) 995.1 973.6 ± 1.3 kJ/mol 157.0074 ± 0.0049 55450-33-4*0 Iodobenzene C6H5I (cr,l) 113.7 113.8 ± 1.1 kJ/mol 204.0084 ± 0.0048 591-50-4*500 Nitrobenzene C6H5N(O)O (g) 82.5 62.5 ± 1.3 kJ/mol 123.1094 ± 0.0049 98-95-3*0 3-Methylenecyclopropene cation [CH2C(CHCH)]+ (g) 1181.8 1174.7 ± 1.2 kJ/mol 52.0740 ± 0.0032 79105-72-9*0 1-Hydroxy-1-methylethyl cation [CH3C(OH)CH3]+ (g) 521.4 501.0 ± 1.2 kJ/mol 59.0865 ± 0.0025 *5131-95-3*0 1-Hydroxypropyl CH3CH2CHOH (g) -55.3 -73.0 ± 1.1 kJ/mol 59.0871 ± 0.0025 5723-77-3*0 1-Oxopropyl CH3CH2CO (g, eclips) -19.1 -31.9 ± 1.1 kJ/mol 57.0712 ± 0.0024 15843-24-0*1 1,1-Dibromoethene CH2CBr2 (g) 130.6 110.2 ± 1.6 kJ/mol 185.8453 ± 0.0026 593-92-0*0 Tribromoethene CHBrCBr2 (g) 169.7 145.0 ± 1.6 kJ/mol 264.7413 ± 0.0034 598-16-3*0 1,1-Diiodoethene CH2CI2 (g) 225.1 217.0 ± 1.6 kJ/mol 279.8462 ± 0.0016 57678-85-0*0 Triiodoethene CHICI2 (g) 302.0 295.5 ± 1.4 kJ/mol 405.7428 ± 0.0016 10065-29-9*0 1,3-Butadien-2-ol CH2C(OH)CHCH2 (g, s-trans, syn) -53.3 -70.3 ± 1.5 kJ/mol 70.0898 ± 0.0032 59120-04-6*11 Cyclopropanone OC(CH2CH2) (g) 30.65 19.22 ± 0.96 kJ/mol 56.0633 ± 0.0024 5009-27-8*0 2-Formylethen-1-ide [CHCHCHO]- (g, anti-trans) 27.4 20.6 ± 2.5 kJ/mol 55.0559 ± 0.0024 135924-69-5*11 Ethenedione OCCO (g) 14.5 17.0 ± 1.2 kJ/mol 56.0202 ± 0.0017 4363-38-6*0 Peroxychlorite [OClOO]- (g, singlet) -34.5 -33.1 ± 1.8 kJ/mol 83.4514 ± 0.0013 852472-63-0*2 Formylamidogen CH(O)NH (g) 76.5 71.1 ± 1.1 kJ/mol 44.03272 ± 0.00087 14753-22-1*0 Formaldonitrone CH2NHO (g) 78.4 67.2 ± 1.4 kJ/mol 45.04066 ± 0.00088 67353-84-8*0 2-Cyclopropen-1-imine (CHCH)CNH (g) 402.0 394.2 ± 1.4 kJ/mol 53.0627 ± 0.0024 31589-17-0*0 1-Isocyanovinyl CH2CNC (g) 519.1 517.3 ± 1.4 kJ/mol 52.0547 ± 0.0024 321850-14-0*0 Peroxychlorous acid HOOClO (g, syn) 95.4 89.4 ± 2.0 kJ/mol 84.4588 ± 0.0013 177778-92-6*1 Vinylvinylidene CH2CHCHC (g, singlet) 494.2 488.8 ± 1.7 kJ/mol 52.0746 ± 0.0032 148759-16-4*2 But-1-en-3-yn-1-ide [HCCCHCH]- (g, trans) 422.5 421.2 ± 1.3 kJ/mol 51.0672 ± 0.0032 119611-65-3*1 Peroxynitrous acid HOONO (g, cis, perp) -0.12 -7.17 ± 0.53 kJ/mol 63.01288 ± 0.00091 14691-52-2*2 Tetrahedryl anion [C(CH(CHCH))]- (g) 634.5 630.7 ± 1.6 kJ/mol 51.0672 ± 0.0032 138805-00-2*0 Silicon carbide SiC (g) 739.3 744.3 ± 2.3 kJ/mol 40.09620 ± 0.00085 409-21-2*0 Silicon carbide SiC (cr, alpha-hex) -70.6 -71.6 ± 1.5 kJ/mol 40.09620 ± 0.00085 409-21-2*501 Trifluorosilylium [SiF3]+ (g) -111.6 -114.4 ± 1.8 kJ/mol 85.08016 ± 0.00030 38192-99-3*0 Silanide [SiH3]- (g) 69.3 63.7 ± 1.3 kJ/mol 31.10987 ± 0.00037 15807-96-2*0 Chlorine fluoride cation [ClF]+ (g) 1165.52 1165.70 ± 0.49 kJ/mol 54.45055 ± 0.00090 12432-44-9*0 Dimethylsilanone CH3Si(O)CH3 (g) -237.4 -252.9 ± 2.3 kJ/mol 74.1539 ± 0.0017 47956-45-6*0 Ethylsilane CH3CH2SiH3 (g) -12.8 -35.3 ± 1.8 kJ/mol 60.1704 ± 0.0017 2814-79-1*0 Perchloric acid HOCl(O)(O)O (g) 11.7 0.2 ± 1.3 kJ/mol 100.4582 ± 0.0015 7601-90-3*0 Hydroxysilyl anion [SiH2OH]- (g, syn) -219.2 -227.2 ± 2.1 kJ/mol 47.10927 ± 0.00047 78450-47-2*1 Triprismane ((CHCH)((CHCH)(CHCH))) (g) 576.0 556.7 ± 1.3 kJ/mol 78.1118 ± 0.0048 650-42-0*0 Propargylallene CH2CCHCH2CCH (g, gauche) 431.5 419.9 ± 1.4 kJ/mol 78.1118 ± 0.0048 33142-15-3*3 1,4-Pentadiyne HCCCH2CCH (g) 460.3 454.7 ± 1.1 kJ/mol 64.0853 ± 0.0040 24442-69-1*0 Nitrosodioxaziridine ONN(OO) (g, trans) 413.6 407.6 ± 1.8 kJ/mol 76.01168 ± 0.00091 132871-99-9*1 Biphenyl C6H5C6H5 (g) 207.0 178.8 ± 1.1 kJ/mol 154.2078 ± 0.0096 92-52-4*0 Diacetylide [CCCCH]- (g) 460.98 466.02 ± 0.96 kJ/mol 49.0513 ± 0.0032 59012-21-4*0 Trioxidaniumyl [HOOOH]+ (g, t, t) 925.5 916.3 ± 1.4 kJ/mol 50.01353 ± 0.00091 161321-37-5*2 Sulfinyl hydride H2SO (g) -40.7 -47.6 ± 1.2 kJ/mol 50.0813 ± 0.0060 25540-60-7*0 Oxygen anion monohydrate [(HOH)O]- (g) -238.9 -244.2 ± 3.0 kJ/mol 34.01523 ± 0.00062 31748-17-1*0 Sulfuric acid OS(O)(OH)2 (aq, 45 H2O) -886.51 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*906 Bisulfite cation [OS(OH)O]+ (g) 554.0 545.3 ± 1.3 kJ/mol 81.0716 ± 0.0061 43637-78-1*0 Sulfur tetraoxide OS(O)(O)O (g, triplet D2d) -228.2 -235.1 ± 2.0 kJ/mol 96.0636 ± 0.0061 12772-98-4*11 Fluorohydrochlorine cation [FClH]+ (g) 975.3 972.3 ± 2.0 kJ/mol 55.45849 ± 0.00090 70110-64-4*0 Thioformaldehyde CH2S (g, singlet) 121.3 117.6 ± 2.0 kJ/mol 46.0926 ± 0.0061 865-36-1*2 Dimethylsulfoxide CH3S(O)CH3 (g) -131.91 -150.55 ± 0.57 kJ/mol 78.1344 ± 0.0062 67-68-5*0 Carbon disulfide SCS (g) 115.90 116.69 ± 0.68 kJ/mol 76.1427 ± 0.0120 75-15-0*0 Hydrogen atom H (ad, 1 Pt(111) atop) -18.9 -21.4 ± 4.3 kJ/mol 1.007940 ± 0.000070 12385-13-6*1002001 Hydrogen atom H (ad, 4 Pt(111) atop) -30.3 -32.7 ± 5.3 kJ/mol 1.007940 ± 0.000070 12385-13-6*1002004 Iminomethide [HCNH]- (g, trans) 237.4 233.5 ± 1.8 kJ/mol 28.03387 ± 0.00082 90623-30-6*1 Diiodide [I2]- (g) -178.13 -180.72 ± 0.48 kJ/mol 253.809489 ± 0.000060 12190-71-5*0 Trifluoromethide [CF3]- (g) -637.7 -639.6 ± 1.8 kJ/mol 69.00646 ± 0.00080 54128-17-5*0 Cyanogen iodide anion [ICN]- (g) 86.5 88.9 ± 8.1 kJ/mol 152.92246 ± 0.00080 1356929-44-6*0 Methanol CH3OH (cr,l) -235.20 -238.54 ± 0.15 kJ/mol 32.04186 ± 0.00090 67-56-1*500 Dihydrogen cation [H2]+ (g) 1488.364 1488.480 ± 0.000 kJ/mol 2.01533 ± 0.00014 12184-90-6*0 Formaldehyde cation [CH2O]+ (g) 944.862 941.241 ± 0.096 kJ/mol 30.02543 ± 0.00087 54288-05-0*0 Isoformyl anion [COH]- (g, triplet) 267.4 268.0 ± 1.6 kJ/mol 29.01859 ± 0.00086 81747-63-9*2 Azanylium [NH2]+ (g) 1266.56 1264.49 ± 0.11 kJ/mol 16.02207 ± 0.00016 15194-15-7*0 1,3-Propanediyl CH2CH2CH2 (g, singlet Cs TS) 358.7 343.8 ± 1.4 kJ/mol 42.0797 ± 0.0024 32458-33-6*22 Diazenide [NNH]- (g, vdW) 175.7 176.7 ± 1.6 kJ/mol 29.02197 ± 0.00016 71004-29-0*100 Allene cation [CH2CCH2]+ (g) 1132.29 1125.14 ± 0.22 kJ/mol 40.0633 ± 0.0024 65812-77-3*0 2-Propenylidene CHCHCH2 (g, triplet anti) 417.6 410.0 ± 1.5 kJ/mol 40.0639 ± 0.0024 19527-08-3*11 2-Propenylidene CHCHCH2 (g, singlet) 452.76 445.63 ± 0.90 kJ/mol 40.0639 ± 0.0024 19527-08-3*2 Cycloprop-1-enylide [CH2(CHC)]- (g) 373.7 369.3 ± 1.7 kJ/mol 39.0565 ± 0.0024 80251-77-0*0 2-Cyclopropen-1-ylium-1-yl [C(CHCH)]+ (g) 1381.9 1380.8 ± 1.1 kJ/mol 38.0474 ± 0.0024 85398-75-0*0 Propynylidene HCCCH (g, cis singlet) 597.9 599.6 ± 1.2 kJ/mol 38.0480 ± 0.0024 67152-18-5*3 Oxochloronium [ClO]+ (g) 1150.86 1150.70 ± 0.66 kJ/mol 51.45155 ± 0.00095 12301-79-0*0 Propenediylidene CHCHC (g) 796.3 797.5 ± 1.4 kJ/mol 38.0480 ± 0.0024 60731-11-5*0 n-Butylium [CH3CH2CH2CH2]+ (g) 827.7 803.4 ± 1.1 kJ/mol 57.1137 ± 0.0033 25453-90-1*0 Ammonium fluoride (NH4)F (cr,l) -452.48 -467.05 ± 0.38 kJ/mol 37.03690 ± 0.00029 12125-01-8*500 2-Butynylium [CH3CCCH2]+ (g, singlet) 1085.9 1077.7 ± 1.3 kJ/mol 53.0820 ± 0.0032 64235-83-2*2 1-Methylene-2-propenyl anion [CH2CHCCH2]- (g) 256.5 246.6 ± 1.3 kJ/mol 53.0830 ± 0.0032 64480-63-3*0 1,3-Butadienyl anion [CH2CHCHCH]- (g) 265.4 255.1 ± 1.5 kJ/mol 53.0830 ± 0.0032 65114-68-3*0 Hypochlorous acid HOCl (aq, undissoc) -125.522 ± 0.050 kJ/mol 52.46004 ± 0.00095 7790-92-3*1000 Ethyloxoniumyl [CH3CH2OH]+ (g) 783.4 766.4 ± 1.7 kJ/mol 46.0679 ± 0.0017 34480-55-2*0 1-Hydroxyethyl CH3CHOH (g, gauche-syn) -41.32 -54.79 ± 0.91 kJ/mol 45.0605 ± 0.0017 2348-46-1*2 1-Hydroxyethylium [CH3CHOH]+ (g) 608.90 594.48 ± 0.37 kJ/mol 45.0600 ± 0.0017 18682-96-7*0 2-Hydroxyethylium [CH2CH2OH]+ (g, staggered-anti) 1019.3 1006.5 ± 1.5 kJ/mol 45.0600 ± 0.0017 38607-31-7*3 Ethyloxoniumylidene [CH3CH2O]+ (g) 988.8 975.1 ± 1.5 kJ/mol 45.0600 ± 0.0017 54387-07-4*0 Acetaldehyde cation [CH3CHO]+ (g) 832.13 822.15 ± 0.22 kJ/mol 44.0520 ± 0.0017 36505-03-0*0 1-Hydroxyethylidene CH3COH (g, gauche triplet) 185.0 175.6 ± 1.4 kJ/mol 44.0526 ± 0.0017 30967-49-8*1 Methoxymethylene CH3OCH (g, gauche triplet) 245.4 235.9 ± 1.4 kJ/mol 44.0526 ± 0.0017 19527-10-7*1 Dioxymethylidyne COO (g) 299.8 301.1 ± 1.7 kJ/mol 44.00950 ± 0.00100 791121-04-5*0 Dioxygen O2 (g, singlet) 94.410 94.383 ± 0.000 kJ/mol 31.99880 ± 0.00060 7782-44-7*2 Oxiranylium [CH2(CHO)]+ (g, triplet) 1233.6 1226.6 ± 1.6 kJ/mol 43.0441 ± 0.0016 57789-76-1*1 Oxiranyl anion [CH2(CHO)]- (g, triplet) 141.0 134.9 ± 1.6 kJ/mol 43.0452 ± 0.0016 72722-59-9*1 Acetic acid CH3C(O)OH (aq) -485.09 ± 0.27 kJ/mol 60.0520 ± 0.0017 64-19-7*800 Ketenyl anion [HCCO]- (g) -48.43 -47.50 ± 0.82 kJ/mol 41.0293 ± 0.0016 64066-01-9*0 Dicarbon monoxide anion [CCO]- (g) 154.18 157.82 ± 0.83 kJ/mol 40.0213 ± 0.0016 87191-88-6*0 Dicarbon monoxide CCO (g, singlet) 440.22 444.55 ± 0.83 kJ/mol 40.0208 ± 0.0016 12071-23-7*2 COC vdW (CO)(C) (g, singlet) 726.2 734.6 ± 1.7 kJ/mol 40.0208 ± 0.0016 *12071-24-8*2 Hydrogen fluoride HF (aq, 20 H2O) -321.83 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*818 C=O-C cation [COC]+ (g, doublet) 1585.8 1592.9 ± 2.7 kJ/mol 40.0203 ± 0.0016 83483-98-1*1 C=O=C anion [COC]- (g) 550.3 554.1 ± 1.7 kJ/mol 40.0213 ± 0.0016 *87191-88-6*0 Oxirene cation [O(CHCH)]+ (g) 1106.2 1102.5 ± 1.8 kJ/mol 42.0361 ± 0.0016 94664-69-4*0 Ethynol HCCOH (g) 95.32 92.83 ± 0.73 kJ/mol 42.0367 ± 0.0016 32038-79-2*0 Hydroxyethenylidene CCHOH (g, syn-triplet) 418.2 414.8 ± 2.4 kJ/mol 42.0367 ± 0.0016 70277-80-4*11 Oxoethylidene HCC(O)H (g, anti-triplet) 265.9 262.6 ± 1.6 kJ/mol 42.0367 ± 0.0016 39920-84-8*11 Hydrogen fluoride HF (aq, 30 H2O) -321.89 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*820 Ammonium nitrate (NH4)NO3 (cr,l) -350.18 -365.14 ± 0.18 kJ/mol 80.04344 ± 0.00095 6484-52-2*500 1-Hydroperoxyethylium [CH3CHOOH]+ (g, trans triplet) 841.6 829.5 ± 1.7 kJ/mol 61.0594 ± 0.0017 *126898-98-4*11 Ammonia NH3 (aq, undissoc) -80.884 ± 0.053 kJ/mol 17.03056 ± 0.00022 7664-41-7*1000 Formic acid cation [HC(O)OH]+ (g, anti) 723.8 716.8 ± 1.2 kJ/mol 46.0248 ± 0.0010 50614-05-6*2 Formic acid anion [HC(O)OH]- (g, syn) -256.1 -262.3 ± 1.8 kJ/mol 46.0259 ± 0.0010 19066-82-1*1 2-Ethylidenedioxidan-2-ium-1-ide CH3CHOO (g, anti) 65.71 53.05 ± 0.63 kJ/mol 60.0520 ± 0.0017 68941-70-8*1 Isocyanic acid cation [HNCO]+ (g) 1003.01 1000.35 ± 0.49 kJ/mol 43.02423 ± 0.00086 444010-28-0*0 Fulminic acid cation [HCNO]+ (g) 1215.7 1212.9 ± 1.3 kJ/mol 43.02423 ± 0.00086 114766-65-3*0 Fluorosyl fluoride FFO (g, triplet) 192.8 193.3 ± 2.3 kJ/mol 53.99621 ± 0.00030 86825-57-2*1 Triiodide [I3]- (g) -254.3 -257.5 ± 3.4 kJ/mol 380.713959 ± 0.000090 14900-04-0*0 1,2-Ethenediol HOCHCHOH (g, trans) -253.9 -266.2 ± 1.3 kJ/mol 60.0520 ± 0.0017 1571-60-4*2 Acetyl chloride CH3C(O)Cl (l) -272.06 ± 0.39 kJ/mol 78.4973 ± 0.0019 75-36-5*500 Methyl formate HC(O)OCH3 (l) -388.45 ± 0.64 kJ/mol 60.0520 ± 0.0017 107-31-3*500 Ethyl formate HC(O)OCH2CH3 (g, anti) -355.3 -374.4 ± 1.4 kJ/mol 74.0785 ± 0.0025 109-94-4*2 Hydroxyimidogen NOH (g) 217.89 215.01 ± 0.78 kJ/mol 31.01408 ± 0.00032 35337-59-8*0 2-Cyclopropyn-1-ylidene C(CC) (g, triplet) 898.4 905.3 ± 1.5 kJ/mol 36.0321 ± 0.0024 102508-15-6*1 Dimethyldioxirane CH3C(CH3)(OO) (g) -88.2 -108.0 ± 1.3 kJ/mol 74.0785 ± 0.0025 74087-85-7*0 Acetoxy CH3C(O)O (g, 2A") -182.02 -190.84 ± 0.76 kJ/mol 59.0440 ± 0.0017 13799-69-4*1 Trihydrogen dioxide anion [HOHOH]- (g) -487.4 -495.7 ± 1.1 kJ/mol 35.02317 ± 0.00064 12501-19-8*0 Nitrous acid HONO (g, cis) -71.38 -77.73 ± 0.26 kJ/mol 47.01348 ± 0.00061 7782-77-6*2 2-Methoxy-2-oxoethyl CH2C(O)OCH3 (g, anti) -172.8 -188.0 ± 1.7 kJ/mol 73.0706 ± 0.0025 54668-31-4*2 2-Cyclopropyn-1-ylium-1-yl [C(CC)]+ (g) 1939.2 1947.1 ± 1.3 kJ/mol 36.0316 ± 0.0024 154702-35-9*0 (Acetyloxy)methyl CH3C(O)OCH2 (g, anti) -173.8 -186.8 ± 1.7 kJ/mol 73.0706 ± 0.0025 2887-49-2*2 Hydroxyoxoethenyl HOCCO (g) 24.5 22.7 ± 1.7 kJ/mol 57.0281 ± 0.0017 702699-39-6*0 Isocyanomethylidyne CNC (g) 672.2 676.5 ± 1.7 kJ/mol 38.0281 ± 0.0016 53590-27-5*0 Cyanomethylidyne CCN (g) 684.7 689.1 ± 2.1 kJ/mol 38.0281 ± 0.0016 4120-02-9*0 Cyanoaminylium [HNCN]+ (g, triplet) 1363.2 1360.9 ± 1.3 kJ/mol 41.03157 ± 0.00082 205443-18-1*1 Cyanoamidogen anion [HNCN]- (g) 69.75 66.74 ± 0.72 kJ/mol 41.03267 ± 0.00082 67131-47-9*0 Diazomethylium [HCNN]+ (g, triplet) 1395.8 1394.1 ± 1.3 kJ/mol 41.03157 ± 0.00082 271249-81-1*1 Diazomethanide [HCNN]- (g) 305.20 302.10 ± 0.76 kJ/mol 41.03267 ± 0.00082 100840-43-5*0 2-Methyliumylidynehydrazin-2-ium-1-ide [HNNC]+ (g, singlet) 1544.2 1542.5 ± 1.7 kJ/mol 41.03157 ± 0.00082 *947408-73-3*2 2-Methyliumylidynehydrazin-2-ium-1-ide [HNNC]+ (g, triplet) 1563.1 1561.5 ± 1.5 kJ/mol 41.03157 ± 0.00082 *947408-73-3*1 Nitrilomethylimidogen NCHN (g, doublet) 728.8 725.7 ± 2.4 kJ/mol 41.03212 ± 0.00082 324529-58-0*1 Methanediimine HNCNH (g) 153.2 146.5 ± 1.3 kJ/mol 42.04006 ± 0.00082 151-51-9*0 Tetrachloromethane CCl4 (l) -104.54 -123.95 ± 0.41 kJ/mol 153.8215 ± 0.0037 56-23-5*500 Dichloromethylene anion [CCl2]- (g) 75.98 78.26 ± 0.77 kJ/mol 82.9166 ± 0.0020 118364-73-1*0 Dichloromethylium [CHCl2]+ (g) 895.4 892.2 ± 1.2 kJ/mol 83.9235 ± 0.0020 56932-33-3*0 Dichloromethide [CHCl2]- (g) -40.7 -42.4 ± 2.0 kJ/mol 83.9246 ± 0.0020 32180-91-9*0 1,3-Butadiyne-1,4-diyl CCCC (g) 1052.24 1062.21 ± 0.64 kJ/mol 48.0428 ± 0.0032 78015-07-3*0 Chloromethylium [CH2Cl]+ (g) 962.4 958.5 ± 1.2 kJ/mol 49.4787 ± 0.0012 59000-00-9*0 Chloromethylene CHCl (g, triplet) 346.24 346.54 ± 0.89 kJ/mol 48.4713 ± 0.0012 2108-20-5*1 1,2-Dichloroethane CH2ClCH2Cl (cr,l) -165.64 ± 0.56 kJ/mol 98.9586 ± 0.0024 107-06-2*500 1,1-Dichloroethane CH3CHCl2 (cr,l) -163.73 ± 0.48 kJ/mol 98.9586 ± 0.0024 75-34-3*500 1,1,2-Trichloroethane CH2ClCHCl2 (l) -187.6 ± 1.1 kJ/mol 133.4033 ± 0.0031 79-00-5*500 Pentachloroethane CHCl2CCl3 (g) -150.5 -156.4 ± 1.9 kJ/mol 202.2928 ± 0.0048 76-01-7*0 Hydroxydioxonitrate [HON(O)O]- (g) -193.2 -197.5 ± 2.4 kJ/mol 63.01343 ± 0.00091 58875-09-5*0 Chloroform CHCl3 (l) -130.82 ± 0.42 kJ/mol 119.3767 ± 0.0028 67-66-3*590 Fluoronium [(HF)(H)]+ (g, triplet) 1490.1 1491.4 ± 1.9 kJ/mol 21.01373 ± 0.00014 12206-67-6*1 Chlorodibromomethane CHClBr2 (g) 22.0 3.2 ± 3.5 kJ/mol 208.2793 ± 0.0023 124-48-1*0 Azidonitrene NNNN (g, Cs) 692.1 687.5 ± 1.4 kJ/mol 56.02696 ± 0.00028 147363-92-6*2 Bromochloromethane CH2ClBr (g) -28.2 -42.3 ± 1.3 kJ/mol 129.3833 ± 0.0016 74-97-5*0 Fluoromethylene CHF (g) 148.40 148.69 ± 0.43 kJ/mol 32.01704 ± 0.00080 13453-52-6*0 Ethyl iodide CH3CH2I (g) 8.71 -7.16 ± 0.48 kJ/mol 155.9656 ± 0.0016 75-03-6*0 Dihydrogen fluoride anion [(F)(HH)]- (g, singlet) -257.0 -260.1 ± 1.9 kJ/mol 21.01483 ± 0.00014 *117339-92-1*2 1,2-Dibromoacetylene BrCCBr (g) 346.5 335.6 ± 2.0 kJ/mol 183.8294 ± 0.0026 624-61-3*0 Fluoro(fluorooxy)methylene FCOF (g, vdW triplet) -97.5 -95.6 ± 1.6 kJ/mol 66.00691 ± 0.00085 479587-30-9*101 Fluorooxomethylium [FCO]+ (g) 724.9 724.6 ± 1.2 kJ/mol 47.00795 ± 0.00085 38264-00-5*0 Fluoroisoformyl COF (g) -37.8 -32.4 ± 1.6 kJ/mol 47.00850 ± 0.00085 *1871-24-5*0 Nitronium [ONO]+ (g) 961.79 958.23 ± 0.20 kJ/mol 46.00499 ± 0.00060 14522-82-8*0 Benzene cation [C6H6]+ (g) 992.59 976.12 ± 0.21 kJ/mol 78.1113 ± 0.0048 34504-50-2*0 Chlorohydrofluorine cation [ClFH]+ (g) 1000.8 998.1 ± 2.1 kJ/mol 55.45849 ± 0.00090 70110-63-3*0 Chlorosyl chloride ClClO (g) 134.5 133.2 ± 1.4 kJ/mol 86.9048 ± 0.0018 86825-56-1*0 Benzocyclopropene CH2(CCHCHCHCHC) (g, singlet) 396.0 379.6 ± 1.5 kJ/mol 90.1225 ± 0.0056 4646-69-9*2 3-Methylphenyl C6H4CH3 (g, meta) 324.5 306.4 ± 1.2 kJ/mol 91.1305 ± 0.0056 3474-41-7*0 2-Methylphenyl C6H4CH3 (g, ortho) 324.5 306.5 ± 1.2 kJ/mol 91.1305 ± 0.0056 22904-44-5*0 4-Methylphenyl C6H4CH3 (g, para) 327.2 309.3 ± 1.2 kJ/mol 91.1305 ± 0.0056 2396-02-3*0 Peroxyimidogen NOO (g) 405.4 403.4 ± 1.9 kJ/mol 46.00554 ± 0.00060 *60488-31-5*0 Indenylium [C6H4(CHCHCH)]+ (g, singlet) 1030.2 1010.7 ± 2.0 kJ/mol 115.1513 ± 0.0072 12203-21-3*2 Benzoic acid C6H5C(O)OH (cr,l) -367.32 -384.74 ± 0.17 kJ/mol 122.1213 ± 0.0056 65-85-0*500 2,3-Dimethylbenzaldehyde CH3C6H3(CH3)C(O)H (g, ortho-meta) -65.7 -93.7 ± 2.4 kJ/mol 134.1751 ± 0.0072 5779-93-1*0 (2,3-dimethylphenyl)oxomethyl CH3C6H3(CH3)CO (g, ortho-meta) 83.3 60.5 ± 2.6 kJ/mol 133.1672 ± 0.0072 *104680-89-9*0 m-Chlorophenide [C6H4Cl]- (g) 172.5 162.3 ± 1.5 kJ/mol 111.5492 ± 0.0049 77748-34-6*0 p-Chlorophenide [C6H4Cl]- (g) 179.5 169.1 ± 1.5 kJ/mol 111.5492 ± 0.0049 77748-42-6*0 o-Chlorophenide [C6H4Cl]- (g) 158.7 148.7 ± 1.5 kJ/mol 111.5492 ± 0.0049 72863-53-7*0 Ethylene cation [CH2CH2]+ (g) 1075.23 1068.01 ± 0.11 kJ/mol 28.0526 ± 0.0016 34470-02-5*0 2-Oxopropylium [CH3C(O)CH2]+ (g) 784.8 771.0 ± 1.7 kJ/mol 57.0707 ± 0.0024 54088-52-7*0 Hydrogen difluoride (F)(HF) (g, perp) -187.4 -187.1 ± 1.6 kJ/mol 39.004746 ± 0.000070 12528-21-1*2 Glycine NH2CH2C(O)OH (cr, alpha) -508.27 -528.37 ± 0.20 kJ/mol 75.0666 ± 0.0017 56-40-6*511 Oxadiazirene O(NN) (g) 351.7 349.9 ± 1.7 kJ/mol 44.01288 ± 0.00033 227934-45-4*0 2,3-Butanedione CH3C(O)C(O)CH3 (g) -310.65 -327.21 ± 0.62 kJ/mol 86.0892 ± 0.0033 431-03-8*0 1,2-Dibromoethane CH2BrCH2Br (g) -11.5 -38.3 ± 1.2 kJ/mol 187.8612 ± 0.0026 106-93-4*0 Chlorine oxide peroxide OClOO (g, vdW) 226.8 227.7 ± 2.2 kJ/mol 83.4509 ± 0.0013 141801-67-4*100 Dimethylketene CH3C(CO)CH3 (g) -73.3 -88.2 ± 1.2 kJ/mol 70.0898 ± 0.0032 598-26-5*0 2-Methyloxirene CH3C(CHO) (g, t-triplet) 344.0 334.0 ± 1.8 kJ/mol 56.0633 ± 0.0024 2835-41-8*11 NON NON (g) 545.5 542.6 ± 1.7 kJ/mol 44.01288 ± 0.00033 227934-46-5*0 3-Oxo-1-propenylium [CHCHCHO]+ (g, anti-trans-triplet) 1185.6 1179.7 ± 3.0 kJ/mol 55.0548 ± 0.0024 101705-90-2*111 (Hydroxyimino)methyl HCNOH (g, trans-trans) 250.2 244.0 ± 1.8 kJ/mol 44.03272 ± 0.00087 206442-92-4*1 Aminohydroxymethylene NH2COH (g, anti-singlet) -22.4 -33.0 ± 1.6 kJ/mol 45.04066 ± 0.00088 160720-48-9*21 1-Isocyanoethylidene CH3CNC (g, triplet) 545.6 540.8 ± 1.6 kJ/mol 53.0627 ± 0.0024 *498544-34-6*1 3-Imino-2-propen-1-ylidene CHCHCNH (g, anti-triplet) 571.9 566.9 ± 1.6 kJ/mol 53.0627 ± 0.0024 916765-05-4*21 2-(Methylidyneamino)ethenyl CHCHNCH (g, anti-triplet) 634.5 629.8 ± 1.6 kJ/mol 53.0627 ± 0.0024 123416-74-0*21 Azete (CHCHCH)N (g) 469.6 461.4 ± 1.5 kJ/mol 53.0627 ± 0.0024 287-24-1*0 1-Chloro ozone ClOOO (g, cis vdW) 226.3 223.1 ± 2.3 kJ/mol 83.4509 ± 0.0013 141801-66-3*101 Dioxygenyl ion monohydrate [(H2O)(O2)]+ (g) 829.1 822.0 ± 2.0 kJ/mol 50.01353 ± 0.00091 11083-61-7*0 2-Cyanovinylium [CHCHCN]+ (g, anti triplet) 1517.3 1515.1 ± 1.8 kJ/mol 52.0542 ± 0.0024 85398-67-0*21 2-Cyanovinyl anion [CHCHCN]- (g, syn) 263.8 260.8 ± 1.8 kJ/mol 52.0553 ± 0.0024 *85398-67-0*2 2-Isocyanovinyl CHCHNC (g, anti) 543.3 541.3 ± 1.7 kJ/mol 52.0547 ± 0.0024 225798-14-1*1 3-Oxo-1,2-propadienylidene CCCO (g) 330.5 336.4 ± 1.8 kJ/mol 52.0315 ± 0.0024 11127-17-6*0 Vinylacetylene cation [CH2CHCCH]+ (g) 1221.8 1215.4 ± 1.1 kJ/mol 52.0740 ± 0.0032 59699-48-8*0 Bicyclo[1.1.0]but-2-ylium-1-yl [CH2(CCH)CH]+ (g) 1287.1 1278.1 ± 1.4 kJ/mol 52.0740 ± 0.0032 *78525-41-4*0 3-Methylene-1-cyclopropen-1-yl anion [CH2C(CHC)]- (g) 417.4 413.6 ± 1.6 kJ/mol 51.0672 ± 0.0032 *117469-28-0*0 2-Cyclopropen-1-ylidenemethyl CHC(CHCH) (g) 635.8 632.7 ± 1.3 kJ/mol 51.0666 ± 0.0032 127611-25-0*0 Fulvenone OCC(CHCHCHCH) (g) 117.3 107.1 ± 1.6 kJ/mol 92.0954 ± 0.0048 4727-22-4*0 Silicon cation Si+ (g) 1236.86 1240.99 ± 0.56 kJ/mol 28.08495 ± 0.00030 14067-07-3*0 Disilicon Si2 (g) 587.5 591.3 ± 1.6 kJ/mol 56.17100 ± 0.00060 12597-35-2*0 Fluorosilyliumylidene [SiF]+ (g) 651.11 652.24 ± 0.98 kJ/mol 47.08335 ± 0.00030 12518-09-1*0 Disiloxane SiH3OSiH3 (g) -330.3 -347.3 ± 2.3 kJ/mol 78.21804 ± 0.00079 13597-73-4*0 Iodotrimethylsilane SiI(CH3)3 (g) -189.7 -214.4 ± 2.1 kJ/mol 200.0935 ± 0.0025 16029-98-4*0 Fluorochlorate [ClF]- (g) -256.03 -255.43 ± 0.81 kJ/mol 54.45165 ± 0.00090 12272-56-9*0 1,2,3,5-Hexatetraene CH2CCCHCHCH2 (g, trans) 391.8 380.0 ± 1.6 kJ/mol 78.1118 ± 0.0048 60239-33-0*1 1,2,3-Pentatriene CH2CCCHCH3 (g) 302.7 290.4 ± 1.4 kJ/mol 66.1011 ± 0.0040 62018-46-6*0 (Z)-1-Methylallyl CH3CHCHCH2 (g, cis) 154.76 137.37 ± 0.99 kJ/mol 55.0984 ± 0.0032 98705-00-1*0 2,4-Cyclopentadien-1-ylidene C(CHCHCHCH) (g, triplet) 526.2 517.2 ± 1.1 kJ/mol 64.0853 ± 0.0040 4729-01-5*1 Ethylammonium [CH3CH2NH3]+ (g) 593.8 568.1 ± 1.4 kJ/mol 46.0911 ± 0.0017 16999-99-8*0 Anthracene C6H4(CH(CC(C4H4)CH)) (g) 255.89 226.72 ± 0.88 kJ/mol 178.2292 ± 0.0112 120-12-7*0 Helium hydride cation [HeH]+ (g) 1350.148 1348.258 ± 0.000 kJ/mol 5.009993 ± 0.000070 17009-49-3*0 Monosulfur anion S- (g) 76.43 78.48 ± 0.14 kJ/mol 32.0665 ± 0.0060 14337-03-2*0 Dibromide [Br2]- (g) -197.0 -211.1 ± 2.3 kJ/mol 159.8085 ± 0.0020 12595-70-9*0 Thiozone SSS (g) 144.28 142.91 ± 0.71 kJ/mol 96.1980 ± 0.0180 12597-03-4*0 Hydrosulfide [SH]- (g) -80.52 -80.52 ± 0.18 kJ/mol 33.0745 ± 0.0060 15035-72-0*0 Hydrogen chloride HCl (aq) -166.990 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*800 Sulfuric acid OS(O)(OH)2 (aq, 2500 H2O) -895.15 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*898 Hydrogen sulfate [OHS(O)(O)O]- (g) -944.0 -954.4 ± 1.4 kJ/mol 97.0721 ± 0.0061 14996-02-2*0 Hydrogen fluoride HF (aq, 10 H2O) -321.69 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*815 Dioxoperoxysulfate [OS(O)OO]- (g, C1) -502.6 -506.5 ± 2.0 kJ/mol 96.0641 ± 0.0061 103613-08-7*1 Dimethyl sulfide CH3SCH3 (cr,l) -63.11 -64.71 ± 0.33 kJ/mol 62.1350 ± 0.0062 75-18-3*500 (Methylthio)methyl CH3SCH2 (g) 149.5 137.8 ± 1.4 kJ/mol 61.1271 ± 0.0062 31533-72-9*0 Hydrogen atom H (ad, 1 Pt(111) fcc) -22.3 -25.6 ± 1.5 kJ/mol 1.007940 ± 0.000070 12385-13-6*1001001 Hydrogen atom H (ad, 4 Pt(111) fcc) -33.4 -36.7 ± 1.5 kJ/mol 1.007940 ± 0.000070 12385-13-6*1001004 Propylidene CH3CH2CH (g, singlet TS anti) 355.7 340.4 ± 2.0 kJ/mol 42.0797 ± 0.0024 6700-78-3*21 Cyclopropylium [CH(CH2CH2)]+ (g, TS) 1101.57 1088.76 ± 0.73 kJ/mol 41.0713 ± 0.0024 1724-43-2*200 Propyne cation [CH3CCH]+ (g) 1192.69 1186.97 ± 0.38 kJ/mol 40.0633 ± 0.0024 34526-53-9*0 Cyclopropylidene C(CH2CH2) (g, triplet) 544.8 536.0 ± 1.5 kJ/mol 40.0639 ± 0.0024 2143-70-6*2 Iminomethide [HCNH]- (g, cis) 252.6 248.9 ± 1.8 kJ/mol 28.03387 ± 0.00082 90623-30-6*2 Aminyliumyl [NH]+ (g) 1659.04 1659.97 ± 0.23 kJ/mol 15.014131 ± 0.000099 19067-62-0*0 Propynylidene cation [HCCCH]+ (g) 1409.62 1412.18 ± 0.82 kJ/mol 38.0474 ± 0.0024 75123-91-0*0 Propynylidene HCCCH (g, trans singlet) 597.6 599.4 ± 1.1 kJ/mol 38.0480 ± 0.0024 67152-18-5*4 Propadienylidenide [CH2CC]- (g) 381.20 382.10 ± 0.40 kJ/mol 38.0485 ± 0.0024 109292-49-1*0 1,2-Propadien-1-ylium-1-yl [CH2CC]+ (g) 1561.6 1562.8 ± 1.4 kJ/mol 38.0474 ± 0.0024 110714-00-6*0 Hydrogen cyanide cation [HCN]+ (g) 1442.54 1442.07 ± 0.20 kJ/mol 27.02483 ± 0.00081 12601-62-6*0 Diazenide [NNH]- (g, triplet) 347.5 344.6 ± 1.6 kJ/mol 29.02197 ± 0.00016 71004-29-0*1 Hydrofluorate ion [HF]- (g) -75.6 -75.1 ± 1.8 kJ/mol 20.006892 ± 0.000070 37249-79-9*0 Dihydrogen fluoride (H)(HF) (g) -55.9 -54.9 ± 1.6 kJ/mol 21.01428 ± 0.00014 12592-22-2*1 Perchlorate [OCl(O)(O)O]- (g) -263.9 -272.8 ± 2.1 kJ/mol 99.4508 ± 0.0015 14797-73-0*0 n-Pentane CH3CH2CH2CH2CH3 (cr,l) -155.81 -172.78 ± 0.29 kJ/mol 72.1488 ± 0.0041 109-66-0*500 iso-Pentane CH3CH2CH(CH3)2 (l) -178.17 ± 0.39 kJ/mol 72.1488 ± 0.0041 78-78-4*500 neo-Pentane C(CH3)4 (l) -189.52 ± 0.38 kJ/mol 72.1488 ± 0.0041 463-82-1*500 Hydroxylamine NH2OH (g, cis) -15.3 -25.9 ± 1.4 kJ/mol 33.02996 ± 0.00037 7803-49-8*2 Cyclopentane CH2(CH2CH2CH2CH2) (l) -104.63 ± 0.38 kJ/mol 70.1329 ± 0.0041 287-92-3*590 Hydrogen peroxide cation [HOOH]+ (g, cis) 931.06 924.21 ± 0.98 kJ/mol 34.01413 ± 0.00062 12325-10-9*2 [1.1.1]Propellane (CH2)3(CC) (g, singlet) 378.6 361.0 ± 1.5 kJ/mol 66.1011 ± 0.0040 35634-10-7*2 Hydroxylamine cation [NH2OH]+ (g) 857.7 847.9 ± 1.6 kJ/mol 33.02941 ± 0.00037 62675-55-2*0 2-Methylpentane CH3CH2CH2CH(CH3)2 (g) -134.45 -173.71 ± 0.73 kJ/mol 86.1754 ± 0.0049 107-83-5*0 3-Methylpentane CH3CH2CH(CH3)CH2CH3 (g) -131.89 -171.40 ± 0.76 kJ/mol 86.1754 ± 0.0049 96-14-0*0 2,3-Dimethylbutane CH3CH(CH3)CH(CH3)CH3 (g) -136.48 -177.58 ± 0.81 kJ/mol 86.1754 ± 0.0049 79-29-8*0 Cyclohexane CH2(CH2CH2CH2CH2CH2) (l) -131.78 -155.91 ± 0.28 kJ/mol 84.1595 ± 0.0049 110-82-7*500 Dihydrooxooxygen cation [(H2O)O]+ (g) 994.9 988.2 ± 1.6 kJ/mol 34.01413 ± 0.00062 177329-59-8*0 1,5-Hexadiene CH2CHCH2CH2CHCH2 (g) 108.52 83.93 ± 0.39 kJ/mol 82.1436 ± 0.0049 592-42-7*0 1-Hydroxyethyl CH3CHOH (g) -42.70 -56.13 ± 0.46 kJ/mol 45.0605 ± 0.0017 2348-46-1*0 Nitrilomethylium [CN]+ (g) 1783.13 1786.61 ± 0.48 kJ/mol 26.01689 ± 0.00080 12539-57-0*0 2-Hydroxyethyl CH2CH2OH (g, staggered-anti) -5.8 -18.2 ± 1.5 kJ/mol 45.0605 ± 0.0017 4422-54-2*3 Nitrogen hydride oxide NH3O (g) 72.2 61.0 ± 1.3 kJ/mol 33.02996 ± 0.00037 38544-48-8*0 Tetraoxidanyl (HOO)(O2) (g, vdW) 2.1 0.4 ± 2.9 kJ/mol 65.0055 ± 0.0012 69696-93-1*100 1-Hydroxyethenyl anion [CH2COH]- (g, syn) 15.1 7.8 ± 2.1 kJ/mol 43.0452 ± 0.0016 112539-13-6*22 Aminooxy cation [NH2O]+ (g) 945.98 938.85 ± 0.76 kJ/mol 32.02147 ± 0.00034 *51375-41-8*0 Dicarbon monoxide cation [CCO]+ (g) 1433.9 1439.0 ± 2.1 kJ/mol 40.0203 ± 0.0016 12287-08-0*0 (E)-Diazene anion [HNNH]- (g, trans) 265.6 258.7 ± 2.0 kJ/mol 30.02991 ± 0.00020 *59952-06-6*0 C=O-C cation [COC]+ (g, quartet) 1816.8 1820.9 ± 2.0 kJ/mol 40.0203 ± 0.0016 83483-98-1*2 Oxirene anion [O(CHCH)]- (g) 288.2 285.2 ± 2.2 kJ/mol 42.0372 ± 0.0016 *157-18-6*0 Hydroxyethenylidene CCHOH (g, singlet) 302.1 300.7 ± 2.1 kJ/mol 42.0367 ± 0.0016 70277-80-4*2 Oxoethylidene HCC(O)H (g, triplet) 261.1 258.3 ± 1.1 kJ/mol 42.0367 ± 0.0016 39920-84-8*1 Methanediol CH2(OH)2 (g) -378.49 -391.58 ± 0.62 kJ/mol 48.0413 ± 0.0010 463-57-0*0 Ethynylene cation [C2]+ (g) 1964.95 1971.54 ± 0.40 kJ/mol 24.0209 ± 0.0016 12595-79-8*0 Ethoxyoxoniumylidene [CH3CH2OO]+ (g, cis singlet) 962.5 946.1 ± 1.6 kJ/mol 61.0594 ± 0.0017 268728-77-4*22 Hydroxyaminylium [HNOH]+ (g, cis) 1048.5 1041.3 ± 2.6 kJ/mol 32.02147 ± 0.00034 66097-71-0*2 2-Hydroperoxyethylium [CH2CH2OOH]+ (g, triplet) 1000.0 989.1 ± 1.6 kJ/mol 61.0594 ± 0.0017 *84824-62-4*1 Hydroxyamidogen anion [HNOH]- (g) 90.7 84.8 ± 2.8 kJ/mol 32.02257 ± 0.00034 *66097-71-0*0 Formic acid anion [HC(O)OH]- (g, anti) -241.2 -246.9 ± 1.9 kJ/mol 46.0259 ± 0.0010 19066-82-1*2 Trichlorine cation [Cl3]+ (g, singlet) 1056.6 1055.5 ± 1.4 kJ/mol 106.3576 ± 0.0027 33088-85-6*2 Dioxirane cation [CH2(OO)]+ (g) 1050.8 1043.2 ± 1.9 kJ/mol 46.0248 ± 0.0010 232262-10-1*0 Dioxymethyl cation [CH2OO]+ (g) 1075.1 1068.7 ± 1.7 kJ/mol 46.0248 ± 0.0010 232262-11-2*0 1-(Dioxidan-2-id-1-yl)ethyl [CH3CHOO]- (g, anti) 27.9 16.3 ± 4.4 kJ/mol 60.0525 ± 0.0017 1646268-48-5*1 1-(Dioxidan-2-id-1-yl)ethyl [CH3CHOO]- (g, syn) 28.3 16.6 ± 4.4 kJ/mol 60.0525 ± 0.0017 1646268-48-5*2 Dioxymethylene HCOO (g, cis) 341.8 339.8 ± 3.0 kJ/mol 45.0174 ± 0.0010 438586-67-5*2 OH-CO vdW complex (OH)(CO) (g, vdW) -80.50 -76.77 ± 0.85 kJ/mol 45.0174 ± 0.0010 *2564-85-4*100 CO-HO vdW complex (CO)(HO) (g, vdW) -77.5 -73.3 ± 1.3 kJ/mol 45.0174 ± 0.0010 *2564-84-3*100 Cyanato cation [NCO]+ (g) 1261.52 1262.02 ± 0.58 kJ/mol 42.01629 ± 0.00086 17247-99-3*0 Nitrosomethyliumylidene [CNO]+ (g) 1509.8 1510.9 ± 1.7 kJ/mol 42.01629 ± 0.00086 67197-19-7*0 Fulminate [CNO]- (g) 59.5 59.8 ± 1.7 kJ/mol 42.01739 ± 0.00086 28269-67-2*0 Ammonium hydroxide NH4OH (cr,l) -360.45 -361.53 ± 0.57 kJ/mol 35.04584 ± 0.00047 1336-21-6*500 Bromine dioxide OBrO (g) 165.6 156.0 ± 2.1 kJ/mol 111.9028 ± 0.0012 21255-83-4*0 Fluoroniumyl ion [HF]+ (g) 1275.556 1275.788 ± 0.022 kJ/mol 20.005795 ± 0.000070 12381-92-9*0 Ammonium hydroxide NH4OH (aq) -362.833 ± 0.061 kJ/mol 35.04584 ± 0.00047 1336-21-6*800 Glyoxal OCHCHO (g, cis) -189.37 -194.82 ± 0.70 kJ/mol 58.0361 ± 0.0017 107-22-2*2 Ethynediol HOCCOH (g) -18.3 -22.1 ± 1.6 kJ/mol 58.0361 ± 0.0017 16005-17-7*0 Chlorite [OClO]- (g) -105.51 -107.68 ± 0.37 kJ/mol 67.4520 ± 0.0011 14998-27-7*0 Dimethylaminylium [(CH3)2N]+ (g) 1040.9 1025.5 ± 1.8 kJ/mol 44.0752 ± 0.0017 49784-85-2*0 Nitrous acid HONO (g) -72.988 -78.645 ± 0.077 kJ/mol 47.01348 ± 0.00061 7782-77-6*0 Ethylimidogen CH3CH2N (g) 306.1 291.5 ± 2.0 kJ/mol 43.0678 ± 0.0016 27770-44-1*0 Trichloride [Cl3]- (g) -328.5 -327.6 ± 1.3 kJ/mol 106.3586 ± 0.0027 18434-33-8*0 Trifluoride ion [F3]- (g) -348.6 -349.4 ± 2.5 kJ/mol 56.9957582 ± 0.0000015 25730-99-8*0 Diisocyanogen CNNC (g) 610.9 613.2 ± 1.7 kJ/mol 52.0349 ± 0.0016 78800-21-2*0 Cyanoamidogen anion [HNCN]- (g, c-triplet) 391.7 389.5 ± 1.8 kJ/mol 41.03267 ± 0.00082 67131-47-9*12 Chlorine difluoride anion [FClF]- (g) -504.9 -505.8 ± 1.9 kJ/mol 73.45005 ± 0.00090 16892-05-0*0 Dioxofluorine OFO (g) 523.9 523.2 ± 1.0 kJ/mol 50.99720 ± 0.00060 175861-93-5*0 Methyleneoxonium cation [CH2OH2]+ (g) 827.8 818.3 ± 1.7 kJ/mol 32.04131 ± 0.00090 *177788-17-9*0 Diazirenide [HC(NN)]- (g) 454.9 452.2 ± 1.5 kJ/mol 41.03267 ± 0.00082 130614-84-5*0 Cyanamide cation [NH2CN]+ (g) 1158.8 1152.4 ± 1.5 kJ/mol 42.03951 ± 0.00082 148556-23-4*0 3-Diaziridinylidene C(NHNH) (g, anti) 521.9 515.0 ± 1.5 kJ/mol 42.04006 ± 0.00082 85513-79-7*1 Diazomethylene CNN (g) 577.9 578.6 ± 2.2 kJ/mol 40.02418 ± 0.00081 2468-81-7*0 (Z)-Diazene cation [HNNH]+ (g, cis) 1157.0 1150.2 ± 1.3 kJ/mol 30.02881 ± 0.00020 86631-37-0*0 Dichloromethylene CCl2 (g, triplet) 313.99 315.20 ± 0.90 kJ/mol 82.9161 ± 0.0020 1605-72-7*1 Chloromethyliumyl [CHCl]+ (g) 1207.4 1207.7 ± 2.0 kJ/mol 48.4708 ± 0.0012 89877-51-0*0 Chloromethylene anion [CHCl]- (g) 203.54 204.35 ± 0.94 kJ/mol 48.4719 ± 0.0012 75466-08-9*0 Chlorohydroxymethyl CH(Cl)OH (g, anti-gauche) -46.0 -51.6 ± 2.0 kJ/mol 65.4787 ± 0.0012 147139-06-8*2 1,1,1,2-Tetrachloroethane CH2ClCCl3 (cr,l) -193.4 ± 1.1 kJ/mol 167.8481 ± 0.0039 630-20-6*500 Hexachloroethane CCl3CCl3 (cr,l) -214.1 ± 2.8 kJ/mol 236.7376 ± 0.0056 67-72-1*500 3-Chloro-3-methyl-3H-diazirine (NN)CClCH3 (g) 251.5 239.6 ± 2.7 kJ/mol 90.5114 ± 0.0019 4222-21-3*0 trans-1,2-Dichloroethene CHClCHCl (g, trans) 5.66 0.24 ± 0.56 kJ/mol 96.9427 ± 0.0024 156-60-5*0 Azidonitrene NNNN (g, C2h) 660.8 657.7 ± 1.6 kJ/mol 56.02696 ± 0.00028 147363-92-6*1 Bromomethylidyne CBr (g) 504.2 500.5 ± 2.1 kJ/mol 91.9147 ± 0.0013 3889-77-8*0 Iodomethylidyne CI (g) 554.8 556.7 ± 2.1 kJ/mol 138.91517 ± 0.00080 3889-78-9*0 Sulfuryl dichloride OS(O)Cl2 (g) -348.06 -354.22 ± 0.75 kJ/mol 134.9702 ± 0.0063 7791-25-5*0 Hydroxymethylene cation [HCOH]+ (g, cis) 986.4 982.8 ± 1.6 kJ/mol 30.02543 ± 0.00087 135395-06-1*2 Hydroxymethylene cation [HCOH]+ (g, gauche quartet) 1482.1 1479.4 ± 1.9 kJ/mol 30.02543 ± 0.00087 135395-06-1*3 Fluorochlorobromomethane CHFClBr (g) -218.3 -230.9 ± 4.9 kJ/mol 147.3737 ± 0.0016 593-98-6*0 Fluoromethyliumyl [CHF]+ (g) 1116.6 1116.9 ± 1.7 kJ/mol 32.01649 ± 0.00080 89877-52-1*0 Fluoromethylene anion [CHF]- (g) 95.95 96.48 ± 0.61 kJ/mol 32.01759 ± 0.00080 71267-42-0*0 Hydroxymethylene anion [HCOH]- (g, cis) 160.2 157.5 ± 1.7 kJ/mol 30.02653 ± 0.00087 207914-87-2*2 Polytetrafluoroethylene CF2CF2 (s) -829.94 ± 0.54 kJ/mol 100.0150 ± 0.0016 9002-84-0*591 Hydroxymethylene anion [HCOH]- (g, gauche quartet) 334.0 334.8 ± 2.1 kJ/mol 30.02653 ± 0.00087 207914-87-2*3 Nitric acid HON(O)O (cr,l) -178.95 -173.23 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*500 trans-1,2-Difluoroethene CHFCHF (g, trans) -299.72 -306.16 ± 0.83 kJ/mol 64.0341 ± 0.0016 1630-78-0*0 Trioxidanylium [HOOO]+ (g, cis) 1085.5 1079.2 ± 1.4 kJ/mol 49.00559 ± 0.00090 74241-49-9*2 Fluoroethynide [CCF]- (g) 133.3 137.5 ± 1.5 kJ/mol 43.0204 ± 0.0016 85905-56-2*0 Formyl fluoride cation [CHFO]+ (g) 816.6 813.3 ± 1.3 kJ/mol 48.01589 ± 0.00086 99766-68-4*0 Formyl fluoride [FCO]- (g) -405.1 -403.7 ± 1.6 kJ/mol 47.00905 ± 0.00085 62227-71-8*0 Aquacarbon H2OC (g, singlet vdW) 467.6 465.5 ± 1.9 kJ/mol 30.02598 ± 0.00087 81434-73-3*102 Fluoroisoformyl cation [COF]+ (g) 1347.4 1349.5 ± 1.9 kJ/mol 47.00795 ± 0.00085 *1871-25-6*0 Trioxidanyl HOOO (g, cis) 26.35 23.08 ± 0.19 kJ/mol 49.00614 ± 0.00090 12500-78-6*2 Aquacarbon cation [H2OC]+ (g) 1196.1 1193.0 ± 1.7 kJ/mol 30.02543 ± 0.00087 *81434-73-3*0 Dihydrogen fluoride anion [(HF)(H)]- (g, singlet) -61.9 -60.5 ± 3.2 kJ/mol 21.01483 ± 0.00014 117339-92-1*2 o-Benzyne cation [C6H4]+ (g) 1392.2 1384.2 ± 1.6 kJ/mol 76.0954 ± 0.0048 70220-84-7*0 m-Benzyne cation [C6H4]+ (g) 1363.1 1354.6 ± 1.5 kJ/mol 76.0954 ± 0.0048 121058-08-0*0 p-Benzyne C6H4 (g, triplet) 603.6 594.2 ± 1.2 kJ/mol 76.0960 ± 0.0048 3355-34-8*1 1-Hydrazinylium-1-yl [NNH2]+ (g) 1143.4 1136.4 ± 1.4 kJ/mol 30.02881 ± 0.00020 63986-30-1*0 Hydrogen fluoride HF (aq, 22 H2O) -321.85 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*902 Dioxaziridinyl cation [N(OO)]+ (g) 1365.9 1363.3 ± 1.7 kJ/mol 46.00499 ± 0.00060 *66252-29-7*0 1,3-Cycloheptadiene CH2(CHCHCHCHCH2CH2) (g, c-c) 123.68 94.57 ± 0.78 kJ/mol 94.1543 ± 0.0056 4054-38-0*1 Tropylium [CH(CHCHCHCHCHCH)]+ (g) 899.22 879.45 ± 0.99 kJ/mol 91.1299 ± 0.0056 26811-28-9*0 Dioxaziridinyl anion [N(OO)]- (g) 295.9 293.4 ± 1.6 kJ/mol 46.00609 ± 0.00060 66252-31-1*0 Ethane cation [CH3CH3]+ (g) 1043.15 1029.14 ± 0.59 kJ/mol 30.0685 ± 0.0017 34488-65-8*0 Peroxyimidogen cation [NOO]+ (g) 1409.6 1406.8 ± 1.9 kJ/mol 46.00499 ± 0.00060 *60488-32-6*0 Hexafluorobenzene C6F6 (cr,l) -997.16 -983.37 ± 0.87 kJ/mol 186.0546 ± 0.0048 392-56-3*500 Chlorine difluoride ClFF (g) 22.5 23.9 ± 1.9 kJ/mol 73.44951 ± 0.00090 91483-78-2*0 Trioxidaniumyl [HOOOH]+ (g, c, t) 935.2 926.1 ± 1.5 kJ/mol 50.01353 ± 0.00091 161321-37-5*3 Peroxyformic acid HC(O)OOH (g, gauche) -265.1 -273.0 ± 1.4 kJ/mol 62.0248 ± 0.0012 107-32-4*3 Ethylene anion [CH2CH2]- (g, anti ?) 232.1 224.4 ± 2.0 kJ/mol 28.0537 ± 0.0016 34527-91-8*1 Peroxyimidogen anion [NOO]- (g) 165.1 162.7 ± 1.7 kJ/mol 46.00609 ± 0.00060 60488-31-5*0 Ethyl nitrite CH3CH2ONO (g) -79.93 -97.33 ± 0.86 kJ/mol 75.0666 ± 0.0017 109-95-5*0 Nirous oxide cation [NNO]+ (g) 1329.70 1326.80 ± 0.12 kJ/mol 44.01233 ± 0.00033 12269-46-4*0 Glycine cation [NH2CH2C(O)OH]+ (g, syn-gauche) 520.3 501.8 ± 2.8 kJ/mol 75.0661 ± 0.0017 35492-82-1*1 Tetrabromoethene CBr2CBr2 (g) 218.8 190.3 ± 2.2 kJ/mol 343.6374 ± 0.0043 79-28-7*0 Oxadiazirine anion [O(NN)]- (g) 95.1 95.5 ± 2.9 kJ/mol 44.01343 ± 0.00033 350586-31-1*0 Tetraiodoethene CI2CI2 (g) 392.2 388.0 ± 2.2 kJ/mol 531.6393 ± 0.0016 513-92-8*0 1,1-Dibromoethane CH3CHBr2 (g) -4.8 -31.8 ± 1.8 kJ/mol 187.8612 ± 0.0026 557-91-5*0 Peroxychlorite [OClOO]- (g, triplet) -116.2 -114.9 ± 2.3 kJ/mol 83.4514 ± 0.0013 852472-63-0*1 Fluorosyl fluoride anion [FFO]- (g, doublet) -147.1 -146.8 ± 3.0 kJ/mol 53.99675 ± 0.00030 *86825-57-2*2 Carbamoyl HNCOH (g, trans-trans) 74.1 67.7 ± 2.7 kJ/mol 44.03272 ± 0.00087 *2858-51-7*1 Formaldiminoxy CH2NO (g) 161.0 154.0 ± 1.5 kJ/mol 44.03272 ± 0.00087 2683-96-7*0 Formaldoxime CH2NOH (g, cis) 50.7 39.8 ± 1.8 kJ/mol 45.04066 ± 0.00088 75-17-2*2 Oxaziridine CH2(NHO) (g) 115.6 103.8 ± 2.1 kJ/mol 45.04066 ± 0.00088 6827-26-5*0 Cyanoethynyl CCCN (g) 715.8 722.2 ± 1.1 kJ/mol 50.0388 ± 0.0024 62435-43-2*0 2-Methylene-2H-azirine (CHN)CCH2 (g) 404.3 397.0 ± 1.7 kJ/mol 53.0627 ± 0.0024 110027-86-6*0 Trioxodinitrate anion [ONN(O)O]- (g, vdW) -104.3 -107.5 ± 1.9 kJ/mol 76.01223 ± 0.00091 194856-62-7*100 2-Cyanovinylium [CHCHCN]+ (g, syn triplet) 1517.5 1515.3 ± 1.8 kJ/mol 52.0542 ± 0.0024 85398-67-0*22 2-Cyanovinyl anion [CHCHCN]- (g, anti) 266.2 263.3 ± 1.8 kJ/mol 52.0553 ± 0.0024 *85398-67-0*1 2-Isocyanovinyl CHCHNC (g, syn) 544.6 542.7 ± 1.7 kJ/mol 52.0547 ± 0.0024 225798-14-1*2 Cyanomethylene HCCN (g, singlet) 529.4 530.4 ± 1.3 kJ/mol 39.0361 ± 0.0016 2612-62-6*2 Isocyanomethylene HCNC (g, triplet) 585.2 586.3 ± 1.6 kJ/mol 39.0361 ± 0.0016 78694-65-2*2 3-Methylcycloprop-3-en-2-ylium-1-yl [CH3C(CHC)]+ (g) 1284.0 1277.5 ± 1.5 kJ/mol 52.0740 ± 0.0032 *185841-59-2*0 Vinylvinylidene cation [CH2CHCHC]+ (g, trans) 1429.9 1424.2 ± 2.0 kJ/mol 52.0740 ± 0.0032 161054-20-2*1 1,2-Butadien-1-ylidene CH3CHCC (g, singlet) 511.8 506.3 ± 2.0 kJ/mol 52.0746 ± 0.0032 119908-55-3*2 1-Buten-3-ynylium [HCCCHCH]+ (g, trans) 1482.5 1480.0 ± 1.4 kJ/mol 51.0661 ± 0.0032 84654-85-3*1 3-Buten-1-ynylium [CH2CHCC]+ (g, triplet) 1572.7 1570.3 ± 1.7 kJ/mol 51.0661 ± 0.0032 103928-84-3*1 3-Methylene-1-cyclopropen-1-ylium [CH2C(CHC)]+ (g, singlet) 1398.8 1395.5 ± 1.7 kJ/mol 51.0661 ± 0.0032 117469-28-0*2 Nitrosyl nitrate ON(O2)NO (g, perp) 70.6 62.3 ± 1.8 kJ/mol 92.0111 ± 0.0012 *15969-55-8*0 Butyraldehyde CH3CH2CH2CHO (g) -185.26 -205.63 ± 0.85 kJ/mol 72.1057 ± 0.0033 123-72-8*0 Chloroallene CH2CCHCl (g) 181.9 175.2 ± 1.6 kJ/mol 74.5086 ± 0.0026 3223-70-9*0 1-Chloropropyne CH3CCCl (g) 192.1 188.0 ± 1.6 kJ/mol 74.5086 ± 0.0026 7747-84-4*0 Methylcyclopentane CH3CH(CH2CH2CH2CH2) (g) -68.58 -106.11 ± 0.36 kJ/mol 84.1595 ± 0.0049 96-37-7*0 Dioxosilane SiO2 (cr,l) -906.77 -911.75 ± 0.63 kJ/mol 60.08430 ± 0.00067 7631-86-9*500 Dioxosilane SiO2 (vitr) -826.32 -902.25 ± 0.64 kJ/mol 60.08430 ± 0.00067 7631-86-9*520 Silicon carbide cation [SiC]+ (g) 1604.8 1609.4 ± 2.4 kJ/mol 40.09565 ± 0.00085 78393-58-5*0 Tetrafluorosilane cation [SiF4]+ (g) -138.1 -142.4 ± 9.4 kJ/mol 104.07856 ± 0.00030 62859-94-3*0 Acetylene anion [HCCH]- (g, trans ?) 356.9 356.7 ± 1.9 kJ/mol 26.0378 ± 0.0016 50443-89-5*1 Difluorosilyliumyl [SiF2]+ (g) 416.0 415.3 ± 2.0 kJ/mol 66.08176 ± 0.00030 37300-76-8*0 Silyliumyl [SiH2]+ (g) 1155.47 1153.85 ± 0.93 kJ/mol 30.10083 ± 0.00033 28149-31-7*0 Fluorodioxidenium [FOO]+ (g) 1221.9 1219.5 ± 2.0 kJ/mol 50.99665 ± 0.00060 139584-95-5*0 Disilanyl anion [SiH3SiH2]- (g) 63.3 50.9 ± 2.1 kJ/mol 61.21125 ± 0.00069 53199-49-8*0 Disilene SiH2SiH2 (g, triplet) 393.4 384.9 ± 2.2 kJ/mol 60.20276 ± 0.00066 15435-77-5*1 Di-mu-hydrodihydrodisilicon HSi(HSiHH) (g, cis-singlet) 385.7 375.3 ± 2.6 kJ/mol 60.20276 ± 0.00066 129970-82-7*22 Fluorine atom cation F+ (g) 1758.301 1760.600 ± 0.017 kJ/mol 18.99785462 ± 0.00000050 14701-13-4*0 Iodosilane SiH3I (g) 6.9 -2.8 ± 2.6 kJ/mol 158.01379 ± 0.00037 13598-42-0*0 Trimethylsilanide [Si(CH3)3]- (g) -42.0 -65.4 ± 2.1 kJ/mol 73.1896 ± 0.0025 54711-92-1*0 Fluorodioxidanide [FOO]- (g) -256.8 -256.1 ± 1.9 kJ/mol 50.99775 ± 0.00060 23553-17-5*0 1-Chloro ozone anion [ClOOO]- (g, perp) -109.0 -111.5 ± 2.1 kJ/mol 83.4514 ± 0.0013 224299-15-4*3 (3E)-1,3-Hexadien-5-yne CH2CHCHCHCCH (g, trans) 358.9 346.6 ± 1.9 kJ/mol 78.1118 ± 0.0048 5222-77-5*0 Divinylacetylene CH2CHCCCHCH2 (g, cis) 361.9 350.5 ± 1.9 kJ/mol 78.1118 ± 0.0048 821-08-9*2 1,2,4-Cyclohexatriene CH2(CHCHCHCCH) (g) 419.5 403.7 ± 2.0 kJ/mol 78.1118 ± 0.0048 124869-33-6*0 1-Chloro ozone anion [ClOOO]- (g, cis) -66.9 -68.8 ± 2.1 kJ/mol 83.4514 ± 0.0013 224299-15-4*1 Ethylammoniumyl [CH3CH2NH2]+ (g) 827.6 807.6 ± 1.6 kJ/mol 45.0832 ± 0.0017 41857-50-5*0 2-Methyl-2-propanamine (CH3)3CNH2 (g) -87.00 -120.65 ± 0.55 kJ/mol 73.1369 ± 0.0033 75-64-9*0 Deuterium atom cation D+ (g) 1532.210 1534.123 ± 0.000 kJ/mol 2.01355319809 ± 0.00000000040 14464-47-2*0 Benzophenone C6H5C(O)C6H5 (g) 80.7 51.5 ± 1.5 kJ/mol 182.2179 ± 0.0104 119-61-9*0 Nitrosyl fluoride FNO (g) -85.48 -87.85 ± 0.76 kJ/mol 49.00454 ± 0.00031 7789-25-5*0 Helium He (g, triplet) 1912.302 1912.302 ± 0.000 kJ/mol 4.0026020 ± 0.0000020 7440-59-7*1 Helium cation He+ (g) 2372.322 2372.322 ± 0.000 kJ/mol 4.0020534 ± 0.0000020 14234-48-1*0 Neonium [NeH]+ (g) 1324.85 1323.04 ± 0.87 kJ/mol 21.18709 ± 0.00060 12200-65-6*0 Kryptonium [KrH]+ (g) 1106.29 1104.50 ± 0.68 kJ/mol 84.8074 ± 0.1000 37276-90-7*0 Monosulfur cation S+ (g) 1276.42 1278.21 ± 0.14 kJ/mol 32.0655 ± 0.0060 14701-12-3*0 Iodine I (g, 2P1/2) 198.109 197.709 ± 0.0021 kJ/mol 126.904470 ± 0.000030 14362-44-8*2 Oxosulfur [SO]+ (g) 999.26 999.87 ± 0.13 kJ/mol 48.0649 ± 0.0060 767269-11-4*0 Bifluoride [FHF]- (g) -705.22 -709.07 ± 0.35 kJ/mol 39.005295 ± 0.000070 18130-74-0*0 Hydrogen oxide sulfide H2OS (g) 51.1 45.1 ± 1.4 kJ/mol 50.0813 ± 0.0060 155348-09-7*0 Sulfuric acid OS(O)(OH)2 (aq, 75 H2O) -887.18 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*825 Sulfuric acid OS(O)(OH)2 (aq, 7000 H2O) -899.22 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*846 Hydrogen sulfite [OS(OH)O]- (g) -684.8 -692.1 ± 1.8 kJ/mol 81.0727 ± 0.0061 15181-46-1*0 Dioxoperoxysulfane (O2S)(OO) (g, singlet C1) -176.7 -177.7 ± 2.1 kJ/mol 96.0636 ± 0.0061 *103613-08-7*11 Dioxoperoxysulfane (O2S)(OO) (g, triplet C1) -296.1 -296.1 ± 2.0 kJ/mol 96.0636 ± 0.0061 *103613-08-7*21 Dioxoperoxysulfate dianion [OS(O)OO]-2 (g, C1) -209.1 -214.8 ± 2.1 kJ/mol 96.0647 ± 0.0061 *14808-79-8*1 Ethanethiol CH3CH2SH (cr,l) -71.48 -73.08 ± 0.37 kJ/mol 62.1350 ± 0.0062 75-08-1*500 Dimethylsulfoxide CH3S(O)CH3 (cr,l) -201.92 -203.58 ± 0.49 kJ/mol 78.1344 ± 0.0062 67-68-5*500 Carbon monosulfide CS (g) 278.91 282.16 ± 0.68 kJ/mol 44.0767 ± 0.0061 2944-05-0*0 Platinum Pt (g) 563.4 564.3 ± 1.7 kJ/mol 195.0780 ± 0.0020 7440-06-4*0 Perchloryloxy OCl(O)(O)O (g) 248.4 240.8 ± 1.8 kJ/mol 99.4503 ± 0.0015 12133-63-0*0 1-Hydroxyethanide [CH3CHOH]- (g) -20.3 -33.7 ± 2.2 kJ/mol 45.0610 ± 0.0017 88032-18-2*0 (Methylmethylene)oxonium [CH3OCH2]+ (g) 686.0 671.7 ± 2.2 kJ/mol 45.0600 ± 0.0017 23653-97-6*0 Methoxymethyl anion [CH3OCH2]- (g) 23.4 10.4 ± 2.3 kJ/mol 45.0610 ± 0.0017 61192-30-1*0 Triiodine cation [I3]+ (g) 946.1 941.0 ± 4.1 kJ/mol 380.712861 ± 0.000090 12596-32-6*0 Acetaldehyde anion [CH3CHO]- (g) -62.1 -72.4 ± 2.2 kJ/mol 44.0531 ± 0.0017 60427-04-5*0 Dichlorine Cl2 (aq, undissoc) -16.473 ± 0.090 kJ/mol 70.9054 ± 0.0018 7782-50-5*1000 Ketene cation [CH2CO]+ (g) 882.24 879.07 ± 0.11 kJ/mol 42.0361 ± 0.0016 64999-16-2*0 Ketene anion [CH2CO]- (g) -16.0 -19.1 ± 2.2 kJ/mol 42.0372 ± 0.0016 56391-79-8*0 Hydrogen chloride HCl (aq, 140 H2O) -165.945 ± 0.024 kJ/mol 36.46064 ± 0.00090 7647-01-0*907 Oxoethenylium [HCCO]+ (g) 1139.7 1142.5 ± 2.1 kJ/mol 41.0282 ± 0.0016 92056-63-8*0 Isocyanomethylium [CH2NC]+ (g) 1272.6 1270.4 ± 2.2 kJ/mol 40.0435 ± 0.0016 78269-43-9*0 Aminooxy anion [NH2O]- (g) 47.3 40.4 ± 1.7 kJ/mol 32.02257 ± 0.00034 51375-41-8*0 Dibromine Br2 (aq) -2.25 ± 0.18 kJ/mol 159.8080 ± 0.0020 7726-95-6*800 Ammonium chloride (NH4)Cl (cr) -311.555 -314.717 ± 0.062 kJ/mol 53.49120 ± 0.00095 12125-02-9*510 Ammonium bromide (NH4)Br (cr) -253.26 -269.84 ± 0.14 kJ/mol 97.9425 ± 0.0010 12124-97-9*510 Oxiranylidene CH2(CO) (g, triplet) 456.1 452.1 ± 2.2 kJ/mol 42.0367 ± 0.0016 50983-85-2*1 Oxiranylidene cation [CH2(CO)]+ (g) 1165.4 1161.9 ± 2.5 kJ/mol 42.0361 ± 0.0016 *50983-85-2*0 Oxiranylidene anion [CH2(CO)]- (g) 236.4 232.4 ± 2.3 kJ/mol 42.0372 ± 0.0016 *50983-86-3*0 Methyl hydroperoxide cation [CH3OOH]+ (g) 833.8 819.7 ± 2.0 kJ/mol 48.0407 ± 0.0010 112465-88-0*0 Nitrosyl nitrate ONONO2 (g, trans) 48.3 40.3 ± 1.8 kJ/mol 92.0111 ± 0.0012 15969-55-8*1 Dihydroxymethylium [CH(OH)2]+ (g, syn-anti) 421.5 410.2 ± 3.0 kJ/mol 47.0328 ± 0.0010 180071-68-5*1 Hydroxymethoxy cation [CH2(OH)O]+ (g, triplet gauche) 925.0 914.7 ± 3.2 kJ/mol 47.0328 ± 0.0010 180071-69-6*13 1-Propenylidene CH3CHC (g, triplet) 630.5 623.0 ± 1.7 kJ/mol 40.0639 ± 0.0024 70277-78-0*2 Oxybismethanol HOCH2OCH2OH (g, C1 I) -534.2 -557.2 ± 1.9 kJ/mol 78.0672 ± 0.0019 4407-89-0*11 Methoxyoxoniumylidene [CH3OO]+ (g) 1012.33 1003.50 ± 0.67 kJ/mol 47.0328 ± 0.0010 86475-50-5*0 Ethylperoxy CH3CH2OO (g, trans) -5.31 -21.41 ± 0.86 kJ/mol 61.0599 ± 0.0017 3170-61-4*1 Formic acid HC(O)OH (cr,l) -431.46 -424.63 ± 0.20 kJ/mol 46.0254 ± 0.0010 64-18-6*500 Dioxirane anion [CH2(OO)]- (g) -173.0 -179.8 ± 3.4 kJ/mol 46.0259 ± 0.0010 *157-26-6*0 Dioxymethyl anion [CH2OO]- (g) 55.1 49.9 ± 1.4 kJ/mol 46.0259 ± 0.0010 93207-29-5*0 Hypofluorous acid cation [HOF]+ (g) 1142.01 1139.00 ± 0.87 kJ/mol 36.00519 ± 0.00031 90243-22-4*0 H-CO2 vdW complex (H)(OCO) (g, vdW) -178.3 -177.5 ± 2.1 kJ/mol 45.0174 ± 0.0010 *2564-83-2*100 1,2-Propadien-1-yl-3-ylidene anion [CCC]- (g) 621.7 629.1 ± 1.3 kJ/mol 36.0326 ± 0.0024 109292-47-9*0 Bromine atom Br (g, 2P3/2) 117.925 111.863 ± 0.055 kJ/mol 79.90400 ± 0.00100 10097-32-2*1 2-Propanol CH3CH(OH)CH3 (cr,l) -305.33 -318.14 ± 0.26 kJ/mol 60.0950 ± 0.0025 67-63-0*500 1-Propanol CH3CH2CH2OH (cr,l) -290.26 -302.44 ± 0.19 kJ/mol 60.0950 ± 0.0025 71-23-8*500 Hydrooxonitrate [HNO]- (g) 78.60 75.68 ± 0.99 kJ/mol 31.01463 ± 0.00032 66057-02-1*0 Imidogen anion [NH]- (g) 322.63 322.68 ± 0.16 kJ/mol 15.015229 ± 0.000099 23841-33-0*0 Oxazirinyl cation [C(NO)]+ (g) 1565.5 1566.2 ± 2.3 kJ/mol 42.01629 ± 0.00086 *228850-18-8*0 Oxazirinyl anion [C(NO)]- (g) 448.2 449.0 ± 2.4 kJ/mol 42.01739 ± 0.00086 28269-68-3*0 Acetic acid CH3C(O)OH (cr,l) -484.02 -483.59 ± 0.18 kJ/mol 60.0520 ± 0.0017 64-19-7*500 Acetic acid CH3C(O)OH (aq, 75 H2O) -484.60 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*825 Acetic acid CH3C(O)OH (aq, 1500 H2O) -484.80 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*840 Nitrate [ON(O)O]- (aq) -206.52 ± 0.18 kJ/mol 62.00549 ± 0.00090 14797-55-8*800 Cyanogen bromide anion [BrCN]- (g) 57.9 54.3 ± 3.8 kJ/mol 105.9220 ± 0.0013 54092-05-6*0 Ethyl formate HC(O)OCH2CH3 (cr,l) -425.8 ± 1.1 kJ/mol 74.0785 ± 0.0025 109-94-4*500 Hydrogen fluoride HF (aq, 40 H2O) -321.92 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*821 Hydroxyimidogen anion [NOH]- (g) 229.8 227.4 ± 2.2 kJ/mol 31.01463 ± 0.00032 *35337-59-8*0 Methylimidogen anion [CH3N]- (g) 321.1 313.4 ± 1.3 kJ/mol 29.04181 ± 0.00083 82539-34-2*0 Hypofluorous acid anion [HOF]- (g, quartet) 155.3 154.7 ± 2.6 kJ/mol 36.00629 ± 0.00031 36505-07-4*2 2-Cyclopropyn-1-ylidene C(CC) (g, singlet) 993.1 1000.0 ± 2.6 kJ/mol 36.0321 ± 0.0024 102508-15-6*2 Propionic acid CH3CH2C(O)OH (g, anti) -415.4 -433.0 ± 1.3 kJ/mol 74.0785 ± 0.0025 79-09-4*2 2-Cyclopropyn-1-yl anion [C(CC)]- (g) 664.5 671.8 ± 1.6 kJ/mol 36.0326 ± 0.0024 500574-36-7*0 2-Propenylidyne anion [CH2CHC]- (g) 464.6 460.9 ± 1.7 kJ/mol 39.0565 ± 0.0024 120126-89-8*0 Imidogen NH (g, triplet) 358.75 358.80 ± 0.16 kJ/mol 15.014680 ± 0.000099 13774-92-0*1 2-Propen-3-yliumylidene [CHCHCH]+ (g) 1494.5 1491.6 ± 1.7 kJ/mol 39.0554 ± 0.0024 84654-86-4*0 (1Z)-Ethanimine CH3CHNH (g, cis) 58.9 44.2 ± 1.4 kJ/mol 43.0678 ± 0.0016 56003-82-8*0 (E)-2-Iminoethylium [CH2CHNH]+ (g, anti-singlet) 1108.4 1097.7 ± 2.9 kJ/mol 42.0594 ± 0.0016 91127-33-2*22 2-Iminoethyl anion [CH2CHNH]- (g, syn) 104.5 93.6 ± 2.1 kJ/mol 42.0604 ± 0.0016 73843-87-5*1 2-Propenylidene anion [CHCHCH]- (g) 536.0 532.6 ± 1.7 kJ/mol 39.0565 ± 0.0024 98705-30-7*0 Hydroxyoxoammoniumyl [HONO]+ (g) 984.1 977.7 ± 1.8 kJ/mol 47.01293 ± 0.00061 80371-48-8*0 Cyanogen cation [NCCN]+ (g) 1598.25 1600.47 ± 0.42 kJ/mol 52.0343 ± 0.0016 37354-81-7*0 Isocyanogen CNCN (g) 412.1 414.4 ± 1.3 kJ/mol 52.0349 ± 0.0016 83951-85-3*0 Diazoethenylidene NNCC (g) 658.6 661.2 ± 1.8 kJ/mol 52.0349 ± 0.0016 130760-10-0*0 Methanol anion [CH3OH]- (g) -89.0 -99.7 ± 2.8 kJ/mol 32.04241 ± 0.00090 68474-04-4*0 Isocyanomethyliumylidene [CNC]+ (g) 1615.7 1621.2 ± 1.9 kJ/mol 38.0276 ± 0.0016 78271-45-1*0 Isocyanomethylidyne anion [CNC]- (g) 479.2 482.9 ± 2.0 kJ/mol 38.0287 ± 0.0016 *53590-27-5*0 Cyanomethyliumylidene [CCN]+ (g) 1719.8 1725.3 ± 2.1 kJ/mol 38.0276 ± 0.0016 76619-90-4*0 Cyanomethylidyne anion [CCN]- (g) 410.0 413.7 ± 2.2 kJ/mol 38.0287 ± 0.0016 12373-35-2*0 2,3-didehydro-1H-azirin-1-yl N(CC) (g) 720.3 724.4 ± 2.1 kJ/mol 38.0281 ± 0.0016 439586-06-8*0 Fluoronium [HFH]+ (g) 774.04 771.10 ± 0.91 kJ/mol 21.01373 ± 0.00014 12206-67-6*0 Methyleneaminylium [CH2N]+ (g, triplet) 1456.7 1453.1 ± 2.1 kJ/mol 28.03277 ± 0.00082 53518-13-1*1 Hydrogen chloride HCl (aq, 74 H2O) -165.545 ± 0.024 kJ/mol 36.46064 ± 0.00090 7647-01-0*953 Diazirinyl HC(NN) (g, 2A') 557.1 553.9 ± 2.0 kJ/mol 41.03212 ± 0.00082 69967-71-1*2 Carbon tetracation [C]+4 (g) 14993.609 14998.755 ± 0.050 kJ/mol 12.00851 ± 0.00080 16092-62-9*0 Water H2O (l, eq.press.) -285.802 ± 0.022 kJ/mol 18.01528 ± 0.00033 7732-18-5*589 Iminomethylimidogen anion [NCHN]- (g, singlet) 401.9 398.6 ± 2.3 kJ/mol 41.03267 ± 0.00082 150296-30-3*2 1H-Diazirin-3-ylium [HN(NC)]+ (g, singlet) 1527.2 1523.7 ± 2.0 kJ/mol 41.03157 ± 0.00082 735234-64-7*2 1H-Diazirin-3-yl HN(NC) (g, quartet) 917.7 914.3 ± 1.9 kJ/mol 41.03212 ± 0.00082 324529-57-9*2 1H-diazirin-3-ide [HN(NC)]- (g, singlet) 379.8 376.7 ± 2.0 kJ/mol 41.03267 ± 0.00082 *735234-64-7*2 1,3-Propanediyl CH2CH2CH2 (g, singlet C2v TS EE) 337.7 323.0 ± 2.2 kJ/mol 42.0797 ± 0.0024 32458-33-6*21 Methanediimine cation [HNCNH]+ (g, cis) 1137.8 1133.1 ± 2.2 kJ/mol 42.03951 ± 0.00082 1189338-16-6*2 Diazomethane cation [CH2NN]+ (g) 1141.94 1135.66 ± 0.87 kJ/mol 42.03951 ± 0.00082 58852-13-4*0 3H-Diazirine cation [CH2(NN)]+ (g) 1327.6 1322.0 ± 1.7 kJ/mol 42.03951 ± 0.00082 796039-16-2*0 Hydroperoxyimidogen HOON (g, trans) 103.3 99.8 ± 2.4 kJ/mol 47.01348 ± 0.00061 877456-58-1*1 1H-Diazirene cation [CH(NHN)]+ (g) 1333.4 1326.3 ± 1.9 kJ/mol 42.03951 ± 0.00082 *157-23-3*0 Isocyanamide cation [NH2NC]+ (g) 1321.4 1316.1 ± 1.9 kJ/mol 42.03951 ± 0.00082 160951-17-7*0 3-Diaziridinylidene cation [C(NHNH)]+ (g, anti) 1479.7 1473.7 ± 2.4 kJ/mol 42.03951 ± 0.00082 *85513-79-7*1 Hydrogen chloride HCl (aq, 1000 H2O) -166.563 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*839 Trichloromethylium [CCl3]+ (g) 856.15 854.63 ± 0.93 kJ/mol 118.3683 ± 0.0028 27130-34-3*0 Aminomethyliumylidene [CNH2]+ (g) 1168.3 1165.1 ± 2.2 kJ/mol 28.03277 ± 0.00082 86784-42-1*0 Dichloromethyliumyl [CCl2]+ (g) 1122.0 1122.9 ± 1.8 kJ/mol 82.9156 ± 0.0020 55945-51-2*0 Fluoroaminyliumyl [NF]+ (g) 1415.09 1415.63 ± 0.85 kJ/mol 33.004595 ± 0.000070 33146-36-0*0 Formaldehyde anion [CH2O]- (g) -26.7 -28.3 ± 2.0 kJ/mol 30.02653 ± 0.00087 27837-46-3*0 Triazirinylium ion [N(NN)]+ (g) 1609.0 1606.1 ± 1.6 kJ/mol 42.01967 ± 0.00021 92220-05-8*0 Formaldehyde CH2O (g, triplet) 196.011 192.708 ± 0.094 kJ/mol 30.02598 ± 0.00087 50-00-0*1 Propynylidene HCCCH (g) 543.73 546.73 ± 0.58 kJ/mol 38.0480 ± 0.0024 67152-18-5*0 Hydrogen chloride HCl (aq, 1250 H2O) -166.604 ± 0.024 kJ/mol 36.46064 ± 0.00090 7647-01-0*954 Triazirine HN(NN) (g) 464.2 457.7 ± 2.6 kJ/mol 43.02816 ± 0.00022 157-29-9*0 1,1,1-Trichloroethane CH3CCl3 (l) -183.82 -177.17 ± 0.53 kJ/mol 133.4033 ± 0.0031 71-55-6*500 3-Methanetetrayl-1,2-cyclopropanediylidene CC(CC) (g) 1154.7 1164.2 ± 1.9 kJ/mol 48.0428 ± 0.0032 78015-08-4*0 Nitric acid cation [HON(O)O]+ (g) 1029.21 1020.14 ± 0.69 kJ/mol 63.01233 ± 0.00091 272109-63-4*0 Vinyl chloride CH2CHCl (cr,l) -3.59 0.98 ± 0.91 kJ/mol 62.4979 ± 0.0018 75-01-4*500 1-Cyclopropene-1,2-diyl CH2(CC) (g) 791.2 790.7 ± 1.5 kJ/mol 38.0480 ± 0.0024 202744-75-0*0 Chloromethane cation [CH3Cl]+ (g) 1014.63 1007.86 ± 0.17 kJ/mol 50.4867 ± 0.0012 12538-71-5*0 Fluorosyl fluoride cation [FFO]+ (g, quartet) 1413.1 1413.4 ± 3.5 kJ/mol 53.99566 ± 0.00030 *86825-50-5*1 Dinitrogen pentoxide O2NONO2 (cr,l) -41.16 ± 0.38 kJ/mol 108.0105 ± 0.0015 10102-03-1*500 2-Cyclopropyn-1-ylidenemethyl anion [CC(CC)]- (g) 800.8 809.8 ± 1.7 kJ/mol 48.0433 ± 0.0032 289679-90-9*0 Hydrogen chloride HCl (aq, 1500 H2O) -166.635 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*840 Bromofluoromethane CH2FBr (g) -197.4 -211.9 ± 4.9 kJ/mol 112.9290 ± 0.0013 373-52-4*0 Fluorodibromomethane CHFBr2 (g) -159.7 -179.3 ± 4.9 kJ/mol 191.8250 ± 0.0022 1868-53-7*0 Difluorochlorobromomethane CF2ClBr (g) -428.9 -439.9 ± 4.9 kJ/mol 165.3642 ± 0.0016 353-59-3*0 Dichlorofluorobromomethane CCl2FBr (g) -228.3 -238.3 ± 4.9 kJ/mol 181.8185 ± 0.0022 353-58-2*0 Dibromofluorochloromethane CBr2FCl (g) -169.9 -186.8 ± 4.9 kJ/mol 226.2698 ± 0.0023 353-55-9*0 Krypton cation Kr+ (g) 1350.756 1350.756 ± 0.000 kJ/mol 83.7995 ± 0.1000 16915-28-9*0 Hydrogen bromide HBr (aq, 600 H2O) -120.01 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*834 Cyclopropenyliumdiyl [CH(CC)]+ (g) 1692.3 1695.3 ± 1.8 kJ/mol 37.0395 ± 0.0024 127476-05-5*0 Cyclopropynyl anion [CH(CC)]- (g) 518.40 521.38 ± 0.76 kJ/mol 37.0406 ± 0.0024 136861-42-2*0 Trioxidanylium [HOOO]+ (g) 1070.7 1064.5 ± 1.4 kJ/mol 49.00559 ± 0.00090 74241-49-9*0 Chlorine difluoride cation [ClFF]+ (g) 1346.3 1344.9 ± 2.1 kJ/mol 73.44896 ± 0.00090 86825-59-4*0 Tetranitrogen cation [NNNN]+ (g) 1392.8 1392.5 ± 1.5 kJ/mol 56.02641 ± 0.00028 12185-04-5*0 1,2-Difluoroacetylene cation [FCCF]+ (g) 1081.7 1084.4 ± 1.3 kJ/mol 62.0177 ± 0.0016 268566-70-7*0 Difluorophosgene cation [CF2O]+ (g) 653.45 650.69 ± 0.51 kJ/mol 66.00636 ± 0.00085 73256-56-1*0 Nitric acid HON(O)O (aq, 1 H2O) -186.79 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*801 Chlorine difluoride anion [ClFF]- (g) -319.0 -319.0 ± 2.2 kJ/mol 73.45005 ± 0.00090 91419-41-9*0 Chloro(chlorooxy)methylene ClCOCl (g, cis) 73.5 73.7 ± 3.6 kJ/mol 98.9155 ± 0.0020 479587-31-0*2 Chlorohydroxymethylene ClCOH (g, trans) 14.0 11.1 ± 2.5 kJ/mol 64.4707 ± 0.0012 147723-60-2*1 (Chlorooxy)methylene HCOCl (g, cis) 119.3 117.9 ± 2.7 kJ/mol 64.4707 ± 0.0012 331419-80-8*2 Dibromophosgene CBr2O (l) -143.98 ± 0.95 kJ/mol 187.8181 ± 0.0022 593-95-3*590 2-Chloroethanol ClCH2CH2OH (l) -314.89 ± 0.53 kJ/mol 80.5132 ± 0.0019 107-07-3*590 2-Bromoethanol BrCH2CH2OH (l) -274.36 ± 0.46 kJ/mol 124.9645 ± 0.0019 540-51-2*590 Nitric acid HON(O)O (aq, 3 H2O) -197.73 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*805 Phenylium [C6H5]+ (g, singlet) 1149.32 1136.54 ± 0.85 kJ/mol 77.1034 ± 0.0048 17333-73-2*2 m-Benzyne anion [C6H4]- (g) 444.6 435.7 ± 1.3 kJ/mol 76.0965 ± 0.0048 249589-31-9*0 p-Benzyne anion [C6H4]- (g) 465.2 455.6 ± 1.3 kJ/mol 76.0965 ± 0.0048 219298-17-6*0 Chlorosyl chloride cation [ClClO]+ (g) 1132.6 1130.8 ± 2.0 kJ/mol 86.9043 ± 0.0018 *86825-56-1*0 Cycloheptane CH2(CH2CH2CH2CH2CH2CH2) (cr,l) -126.54 -156.43 ± 0.50 kJ/mol 98.1861 ± 0.0057 291-64-5*500 Ethylbenzene C6H5CH2CH3 (cr,l) -12.30 ± 0.52 kJ/mol 106.1650 ± 0.0064 100-41-4*500 Phenylacetylene C6H5CCH (cr,l) 273.87 ± 0.70 kJ/mol 102.1332 ± 0.0064 536-74-3*500 Indane C6H4(CH2CH2CH2) (cr,l) 25.43 10.95 ± 0.76 kJ/mol 118.1757 ± 0.0072 496-11-7*500 Chlorosyl chloride anion [ClClO]- (g) -185.4 -184.7 ± 2.3 kJ/mol 86.9053 ± 0.0018 *86825-55-0*0 Indene cation [C6H4(CHCHCH2)]+ (g) 969.97 946.73 ± 0.73 kJ/mol 116.1593 ± 0.0072 42949-13-3*0 Indene C6H4(CHCHCH2) (cr,l) 117.25 109.96 ± 0.85 kJ/mol 116.1598 ± 0.0072 95-13-6*500 Phenyloxoniumylidene [C6H5O]+ (g) 898.7 884.4 ± 1.4 kJ/mol 93.1028 ± 0.0048 41071-17-4*0 Hydrogen bromide HBr (aq, 1250 H2O) -120.14 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*954 Fluorobenzene C6H5F (cr,l) -148.76 -146.34 ± 0.39 kJ/mol 96.1023 ± 0.0048 462-06-6*500 Chloryl chloride ClCl(O)O (g) 126.1 122.1 ± 1.7 kJ/mol 102.9042 ± 0.0019 117489-73-3*0 Ethanium [C2H7]+ (g, classical Cs I) 888.8 870.3 ± 1.8 kJ/mol 31.0764 ± 0.0017 24669-33-8*2 Ethanium [C2H7]+ (g, classical Cs II) 895.2 877.3 ± 1.9 kJ/mol 31.0764 ± 0.0017 24669-33-8*3 Bromobenzene C6H5Br (cr,l) 60.3 ± 1.3 kJ/mol 157.0079 ± 0.0049 108-86-1*500 Hypochlorous acid cation [HOCl]+ (g) 998.94 995.90 ± 0.90 kJ/mol 52.45949 ± 0.00095 71606-47-8*0 2-Butynylium [CH3CCCH2]+ (g, triplet) 1258.8 1251.5 ± 1.6 kJ/mol 53.0820 ± 0.0032 64235-83-2*1 Pyridinium [NH(CHCHCHCHCH)]+ (g) 761.7 740.8 ± 1.3 kJ/mol 80.1073 ± 0.0040 16969-45-2*0 Acetone CH3C(O)CH3 (cr,l) -244.53 -247.64 ± 0.26 kJ/mol 58.0791 ± 0.0025 67-64-1*500 2-Hydroxy-2-propenyl CH2C(OH)CH2 (g) 4.0 -9.5 ± 1.2 kJ/mol 57.0712 ± 0.0024 742072-56-6*0 Ethylene anion [CH2CH2]- (g, syn ?) 231.6 225.5 ± 2.0 kJ/mol 28.0537 ± 0.0016 34527-91-8*2 Propionaldehyde CH3CH2CHO (cr,l) -217.90 -216.44 ± 0.24 kJ/mol 58.0791 ± 0.0025 123-38-6*500 Hydrogen fluoride HF (aq, 60 H2O) -321.97 ± 0.10 kJ/mol 20.006343 ± 0.000070 7664-39-3*823 Nirous oxide anion [NNO]- (g) 99.3 96.7 ± 1.9 kJ/mol 44.01343 ± 0.00033 12274-12-3*0 Ozone cation [OOO]+ (g) 1352.880 1350.541 ± 0.041 kJ/mol 47.99765 ± 0.00090 12596-82-6*0 Difluoronitrate [NF2]- (g) -70.7 -72.6 ± 1.9 kJ/mol 52.004095 ± 0.000070 37366-64-6*0 1-Ethylium-1-yl [CH3CH]+ (g) 1182.0 1174.7 ± 3.2 kJ/mol 28.0526 ± 0.0016 85944-79-2*0 1-Methylene-2-propenylium [CH2CHCCH2]+ (g, singlet) 1059.5 1049.4 ± 1.7 kJ/mol 53.0820 ± 0.0032 62698-26-4*2 1-Methylene-2-propenylium [CH2CHCCH2]+ (g, triplet) 1256.4 1246.7 ± 1.7 kJ/mol 53.0820 ± 0.0032 62698-26-4*1 trans-1,2-Diiodoethene CHICHI (g, trans) 215.19 207.80 ± 0.35 kJ/mol 279.8462 ± 0.0016 590-27-2*0 Ethylidene anion [CH3CH]- (g) 325.7 318.4 ± 1.8 kJ/mol 28.0537 ± 0.0016 35829-99-3*0 Monoammonium succinate (CH2C(O)OH)2(NH3) (cr) -1067.85 ± 0.72 kJ/mol 135.1186 ± 0.0035 38457-08-8*510 Diammonium succinate (CH2COOH)2(NH3)2 (cr) -1182.36 ± 0.47 kJ/mol 152.1492 ± 0.0035 2226-88-2*510 Acrolein CH2CHCHO (g, cis) -46.3 -56.7 ± 1.3 kJ/mol 56.0633 ± 0.0024 107-02-8*2 2H-Oxete O(CH2CHCH) (g) 65.8 53.3 ± 1.2 kJ/mol 56.0633 ± 0.0024 287-25-2*0 Hydrogen bromide HBr (aq, 5000 H2O) -120.30 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*844 1-Formylethenylium [CH2CCHO]+ (g, singlet) 1023.5 1018.0 ± 2.3 kJ/mol 55.0548 ± 0.0024 101705-89-9*2 3-Oxo-1-propenylium [CHCHCHO]+ (g, singlet) 1005.1 1002.8 ± 2.4 kJ/mol 55.0548 ± 0.0024 101705-90-2*2 Ethenedione cation [OCCO]+ (g) 909.5 912.6 ± 2.0 kJ/mol 56.0197 ± 0.0017 12541-99-0*0 Hypochlorous acid anion [HOCl]- (g) 198.7 198.4 ± 2.5 kJ/mol 52.46059 ± 0.00095 34524-94-2*0 Hydrogen difluoride cation [FFH]+ (g, singlet) 1174.3 1171.3 ± 1.5 kJ/mol 39.004198 ± 0.000070 *126950-54-7*2 1,3-Butadienylium [CH2CHCHCH]+ (g, singlet) 1133.7 1123.7 ± 2.5 kJ/mol 53.0820 ± 0.0032 86181-69-3*2 Fluorosyl fluoride anion [FFO]- (g, quartet) -56.6 -55.7 ± 2.4 kJ/mol 53.99675 ± 0.00030 *86825-57-2*1 3-Imino-2-propen-1-ylidene CHCHCNH (g, anti-singlet) 533.0 527.9 ± 1.8 kJ/mol 53.0627 ± 0.0024 916765-05-4*12 3-Imino-2-propen-1-ylidene CHCHCNH (g, syn-triplet) 572.6 567.3 ± 2.0 kJ/mol 53.0627 ± 0.0024 916765-05-4*22 2-(Methylidyneamino)ethenyl CHCHNCH (g, syn-singlet) 604.5 599.7 ± 1.9 kJ/mol 53.0627 ± 0.0024 123416-74-0*12 2-(Methylidyneamino)ethenyl CHCHNCH (g, syn-triplet) 637.1 632.3 ± 2.0 kJ/mol 53.0627 ± 0.0024 123416-74-0*22 1-Cyanovinylium [CH2CCN]+ (g) 1318.3 1317.1 ± 2.2 kJ/mol 52.0542 ± 0.0024 85399-09-3*0 Hydrogen carbonate [HOC(O)O]- (aq) -689.864 ± 0.039 kJ/mol 61.0174 ± 0.0012 71-52-3*800 Ammonium radical NH4 (g) 190.01 179.42 ± 0.43 kJ/mol 18.03850 ± 0.00029 92075-50-8*0 Tetraoxygen O4 (g, C2h singlet) 145.8 142.2 ± 3.8 kJ/mol 63.9976 ± 0.0012 12596-83-7*22 Butatriene cation [CH2CCCH2]+ (g) 1210.6 1204.8 ± 1.3 kJ/mol 52.0740 ± 0.0032 65513-85-1*0 Bicyclo[1.1.0]but-3-ene CH2(CCH)CH (g) 483.2 474.2 ± 1.6 kJ/mol 52.0746 ± 0.0032 78525-41-4*0 Vinylvinylidene anion [CH2CHCHC]- (g, trans) 405.8 399.0 ± 2.0 kJ/mol 52.0751 ± 0.0032 167386-49-4*1 Hydrogen fluoride HF (aq, 18 H2O) -321.82 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*901 Tetrahedrane cation [CH(CH(CHCH))]+ (g) 1326.8 1318.6 ± 1.7 kJ/mol 52.0740 ± 0.0032 80826-01-3*0 Bicyclo[1.1.0]but-1(3)-ene CH2(CC)CH2 (g) 578.8 570.4 ± 1.9 kJ/mol 52.0746 ± 0.0032 58208-49-4*0 Bicyclo[1.1.0]but-1(3)-ene cation [CH2(CC)CH2]+ (g) 1461.7 1453.6 ± 2.1 kJ/mol 52.0740 ± 0.0032 *58208-49-4*0 1-Buten-3-yn-1-yl HCCCHCH (g, cis) 547.9 545.2 ± 1.2 kJ/mol 51.0666 ± 0.0032 2810-61-9*2 3-Buten-1-ynylium [CH2CHCC]+ (g, singlet) 1603.9 1603.0 ± 1.7 kJ/mol 51.0661 ± 0.0032 103928-84-3*2 3-Methylene-1-cyclopropen-1-ylium [CH2C(CHC)]+ (g, triplet) 1467.7 1464.1 ± 1.6 kJ/mol 51.0661 ± 0.0032 117469-28-0*1 2-Cyclopropen-1-ylidenemethylium [CHC(CHCH)]+ (g, singlet) 1346.5 1343.9 ± 1.8 kJ/mol 51.0661 ± 0.0032 112936-36-4*2 1,3-Cyclobutadien-1-ylium [C(CHCHCH)]+ (g, singlet) 1388.4 1383.4 ± 1.8 kJ/mol 51.0661 ± 0.0032 81913-77-1*2 Cyanic azide NCNNN (g) 502.8 498.3 ± 1.9 kJ/mol 68.03766 ± 0.00085 764-05-6*0 Phenyl hydroperoxide C6H5OOH (g) 13.8 -5.2 ± 2.1 kJ/mol 110.1106 ± 0.0049 36112-26-2*0 trans-1,3,5-Hexatriene CH2CHCHCHCHCH2 (g, trans) 184.1 164.2 ± 2.4 kJ/mol 80.1277 ± 0.0048 821-07-8*0 Methylcyclopentadienyl CH3C(CHCHCHCH) (g) 239.0 221.4 ± 2.1 kJ/mol 79.1198 ± 0.0048 72348-44-8*0 Methylcyclopentane CH3CH(CH2CH2CH2CH2) (cr,l) -116.53 -137.89 ± 0.35 kJ/mol 84.1595 ± 0.0049 96-37-7*500 Dioxosilane SiO2 (cr, cristobalite) -904.07 -908.93 ± 0.68 kJ/mol 60.08430 ± 0.00067 7631-86-9*510 Cyclopentene CH2(CH2CHCHCH2) (l) 7.40 ± 0.48 kJ/mol 68.1170 ± 0.0040 142-29-0*590 Fluorosilylidyne SiF (g) -60.32 -58.48 ± 0.62 kJ/mol 47.08390 ± 0.00030 11128-24-8*0 Deuterium hydride cation [HD]+ (g) 1490.498 1490.587 ± 0.000 kJ/mol 3.021493 ± 0.000070 12181-16-7*0 Hydrogen fluoride HF (aq, 5 H2O) -321.318 ± 0.099 kJ/mol 20.006343 ± 0.000070 7664-39-3*809 Acetylene anion [HCCH]- (g, cis ?) 380.1 380.4 ± 1.9 kJ/mol 26.0378 ± 0.0016 50443-89-5*2 Silylene anion [SiH2]- (g) 167.2 165.6 ± 1.4 kJ/mol 30.10193 ± 0.00033 54991-62-7*0 Silyliumylidene [SiH]+ (g) 1136.49 1137.70 ± 0.80 kJ/mol 29.09289 ± 0.00031 31241-66-4*0 Chloroniumyl ion [HCl]+ (g) 1137.798 1137.732 ± 0.0051 kJ/mol 36.46009 ± 0.00090 12258-94-5*0 Disilene cation [SiH2SiH2]+ (g) 1069.5 1060.4 ± 2.0 kJ/mol 60.20221 ± 0.00066 108492-63-3*0 Di-mu-hydrodihydrodisilicon cation [HSi(HSiHH)]+ (g, trans) 1180.3 1172.7 ± 3.2 kJ/mol 60.20221 ± 0.00066 *129970-82-7*1 Di-mu-hydrodihydrodisilicon anion [HSi(HSiHH)]- (g, trans) 288.5 280.0 ± 3.3 kJ/mol 60.20331 ± 0.00066 *129970-83-8*1 mu-Hydrotrihydrodisilicon Si(HSiH3) (g, triplet) 459.2 450.9 ± 2.5 kJ/mol 60.20276 ± 0.00066 497967-55-2*1 Acetylene HCCH (g, cis-triplet) 599.3 599.1 ± 1.4 kJ/mol 26.0373 ± 0.0016 74-86-2*11 Vinylsilane CH2CHSiH3 (g) 107.9 92.5 ± 2.2 kJ/mol 58.1545 ± 0.0017 7291-09-0*0 Carbon C (g, triplet) 711.393 716.878 ± 0.040 kJ/mol 12.01070 ± 0.00080 7440-44-0*1 Tribromine Br3 (g) 156.0 134.3 ± 3.2 kJ/mol 239.7120 ± 0.0030 11094-39-6*0 Diazenium [NH2NH]+ (g) 968.67 957.41 ± 0.73 kJ/mol 31.03675 ± 0.00025 37369-93-0*0 Peroxychloric acid HOOCl(O)O (g) 76.6 68.4 ± 2.5 kJ/mol 100.4582 ± 0.0015 177778-91-5*0 Tribromide [Br3]- (g) -287.4 -308.5 ± 1.9 kJ/mol 239.7125 ± 0.0030 14522-80-6*0 Dewar benzene (CHCH)(CHCHCHCH) (g) 422.2 405.1 ± 1.7 kJ/mol 78.1118 ± 0.0048 5649-95-6*0 Methylammoniumyl [CH3NH2]+ (g) 865.99 852.05 ± 0.25 kJ/mol 31.05659 ± 0.00088 34516-31-9*0 1,2-Hexadien-4-yne CH2CCHCCCH3 (g) 407.5 397.5 ± 1.7 kJ/mol 78.1118 ± 0.0048 34783-10-3*0 3-Methylene-1-penten-4-yne CH2CHC(CH2)CCH (g, trans) 362.7 350.1 ± 2.2 kJ/mol 78.1118 ± 0.0048 6929-96-0*1 3-Methyl-1,4-pentadiyne HCCCH(CH3)CCH (g) 439.1 427.7 ± 1.6 kJ/mol 78.1118 ± 0.0048 57242-04-3*0 Dioxodiazoxane ONONO (g, t, c) 109.3 105.3 ± 1.8 kJ/mol 76.01168 ± 0.00091 122413-35-8*2 Methylamine anion [CH3NH2]- (g) 84.2 69.4 ± 2.8 kJ/mol 31.05769 ± 0.00088 81096-79-9*0 Ethylaminylium [CH3CH2NH]+ (g, syn-triplet) 1092.4 1076.5 ± 2.4 kJ/mol 44.0752 ± 0.0017 54387-08-5*11 Hydrogen chloride HCl (aq, 75 H2O) -165.555 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*825 2-Methyl-2-propanamine (CH3)3CNH2 (cr,l) -133.10 -150.59 ± 0.53 kJ/mol 73.1369 ± 0.0033 75-64-9*500 1,2-Diphenylethane C6H5CH2CH2C6H5 (cr,l) 84.82 51.08 ± 0.75 kJ/mol 182.2610 ± 0.0112 103-29-7*500 Anthracene C6H4(CH(CC(C4H4)CH)) (cr,l) 151.29 125.48 ± 0.84 kJ/mol 178.2292 ± 0.0112 120-12-7*500 Phenanthrene C6H4(C2H2(CC(C4H4))) (cr,l) 136.33 111.05 ± 0.64 kJ/mol 178.2292 ± 0.0112 85-01-8*500 Diphenylacetylene C6H5CCC6H5 (g) 432.4 407.3 ± 1.2 kJ/mol 178.2292 ± 0.0112 501-65-5*0 Diphenylacetylene C6H5CCC6H5 (cr,l) 334.68 312.73 ± 0.93 kJ/mol 178.2292 ± 0.0112 501-65-5*500 Benzophenone C6H5C(O)C6H5 (cr,l) -16.7 -41.9 ± 1.5 kJ/mol 182.2179 ± 0.0104 119-61-9*500 Bicyclo[1.1.0]buta-1,1-diene-2,4-diyl C(CCH)C (g) 990.4 993.6 ± 2.0 kJ/mol 49.0507 ± 0.0032 *99417-53-5*0 Benzoic acid C6H5C(O)OH (g) -274.33 -294.13 ± 0.19 kJ/mol 122.1213 ± 0.0056 65-85-0*0 Argonium [ArH]+ (g) 1151.8 1150.1 ± 1.4 kJ/mol 40.9554 ± 0.0010 12254-68-1*0 Carbon C (g, singlet) 833.324 838.470 ± 0.040 kJ/mol 12.01070 ± 0.00080 7440-44-0*2 Xenonium [XeH]+ (g) 1038.20 1036.42 ± 0.88 kJ/mol 132.2974 ± 0.0200 37276-91-8*0 Sulfur dioxide OSO (aq, undissoc) -320.69 ± 0.14 kJ/mol 64.0648 ± 0.0060 7446-09-5*1000 Trifluorine cation [F3]+ (g) 1530.0 1527.9 ± 2.2 kJ/mol 56.9946610 ± 0.0000015 64710-22-1*0 Sulfur oxide peroxide OSOO (g, cis) -26.0 -30.2 ± 2.3 kJ/mol 80.0642 ± 0.0061 175799-68-5*2 Trisulfide [SSS]- (g) -83.72 -84.64 ± 0.71 kJ/mol 96.1985 ± 0.0180 12597-04-5*0 Cyclohexene CH2(CHCHCH2CH2CH2) (g) 27.19 -4.28 ± 0.32 kJ/mol 82.1436 ± 0.0049 110-83-8*0 Cyclohexene CH2(CHCHCH2CH2CH2) (cr,l) -21.96 -37.83 ± 0.30 kJ/mol 82.1436 ± 0.0049 110-83-8*500 iso-Proplylide [CH3CHCH3]- (g) 128.8 110.4 ± 1.5 kJ/mol 43.0882 ± 0.0024 25012-80-0*0 Aminomethyl anion [CH2NH2]- (g) 209.5 199.2 ± 2.1 kJ/mol 30.04975 ± 0.00085 74215-21-7*0 Propylene cation [CH3CHCH2]+ (g) 975.20 961.67 ± 0.18 kJ/mol 42.0792 ± 0.0024 34504-10-4*0 Sulfuric acid OS(O)(OH)2 (aq, 115 H2O) -887.70 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*893 2-Chloro ozone anion [ClO(O)O]- (g) -103.6 -105.9 ± 3.2 kJ/mol 83.4514 ± 0.0013 *141801-67-4*0 Sulfuric acid OS(O)(OH)2 (aq, 30 H2O) -885.87 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*820 Sulfuric acid OS(O)(OH)2 (aq, 50 H2O) -886.66 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*822 Sulfuric acid OS(O)(OH)2 (aq, 10000 H2O) -900.64 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*850 Methylaminilium [CH3NH]+ (g) 1135.2 1125.4 ± 2.1 kJ/mol 30.04865 ± 0.00085 49784-84-1*0 Sulfur tetraoxide OS(O)(O)O (g, singlet Td) -163.8 -169.6 ± 2.9 kJ/mol 96.0636 ± 0.0061 12772-98-4*22 Dioxoperoxysulfane (O2S)(OO) (g, triplet Cs ?) -295.8 -295.5 ± 2.7 kJ/mol 96.0636 ± 0.0061 *103613-08-7*22 Methyliumylamino [CH2NH]+ (g) 1056.1 1049.2 ± 1.7 kJ/mol 29.04071 ± 0.00083 65130-65-6*0 Methanethiol CH3SH (cr,l) -46.75 -44.57 ± 0.44 kJ/mol 48.1085 ± 0.0061 74-93-1*500 Azanidylmethyl [CH2NH]- (g) 224.4 217.1 ± 2.2 kJ/mol 29.04181 ± 0.00083 127593-73-1*0 Hydroxydimethylsulfur CH3S(OH)CH3 (g) -19.7 -37.7 ± 2.6 kJ/mol 79.1424 ± 0.0062 52670-37-8*0 Aminomethyliumyl [CHNH2]+ (g) 1039.5 1031.8 ± 2.3 kJ/mol 29.04071 ± 0.00083 89302-94-3*0 Carbon disulfide SCS (cr,l) 78.25 89.05 ± 0.69 kJ/mol 76.1427 ± 0.0120 75-15-0*500 Hydrogen atom H (ad, 1 Pt(111)) -22.3 -24.0 ± 1.5 kJ/mol 1.007940 ± 0.000070 12385-13-6*1000001 Aminomethylene anion [CHNH2]- (g) 353.0 346.1 ± 2.3 kJ/mol 29.04181 ± 0.00083 207914-86-1*0 Hydrogen atom H (ad, 1 Pt(111) hcp) -17.0 -20.2 ± 5.2 kJ/mol 1.007940 ± 0.000070 12385-13-6*1003001 Hydrogen atom H (ad, 1 Pt(111) bridge) -14.1 -17.0 ± 8.5 kJ/mol 1.007940 ± 0.000070 12385-13-6*1004001 Hydrogen atom H (ad, 4 Pt(111) hcp) -30.3 -33.4 ± 7.2 kJ/mol 1.007940 ± 0.000070 12385-13-6*1003004 Hydrogen atom H (ad, 4 Pt(111) bridge) -28.3 -31.1 ± 7.6 kJ/mol 1.007940 ± 0.000070 12385-13-6*1004004 Formyloxidanyl HC(O)O (g) -125.76 -127.12 ± 0.55 kJ/mol 45.0174 ± 0.0010 16499-21-1*0 Dioxiranyl HC(OO) (g) 217.3 213.9 ± 2.0 kJ/mol 45.0174 ± 0.0010 120595-16-6*0 1,2-Propadien-1-ylium-1-yl-3-ylidene [CCC]+ (g, lin) 1957.18 1965.05 ± 0.82 kJ/mol 36.0316 ± 0.0024 118090-85-0*1 1-Propynylium [CH3CC]+ (g) 1547.1 1545.1 ± 3.1 kJ/mol 39.0554 ± 0.0024 24858-94-4*0 Diethyl ether CH3CH2OCH2CH3 (cr,l) -265.24 -277.55 ± 0.75 kJ/mol 74.1216 ± 0.0033 60-29-7*500 1-Butanol CH3CH2CH2CH2OH (cr,l) -312.82 -327.10 ± 0.21 kJ/mol 74.1216 ± 0.0033 71-36-3*500 2-Methyl-2-propanol (CH3)3COH (g) -282.0 -312.1 ± 1.9 kJ/mol 74.1216 ± 0.0033 75-65-0*0 Isocyanogen chloride ClNC (g) 314.7 316.3 ± 2.4 kJ/mol 61.4701 ± 0.0012 75754-69-7*0 Oxobromonium [BrO]+ (g) 1140.0 1132.2 ± 1.6 kJ/mol 95.9029 ± 0.0010 142315-39-7*0 Cycloprop-1-enylium [CH2(CHC)]+ (g) 1502.3 1498.0 ± 2.2 kJ/mol 39.0554 ± 0.0024 117067-78-4*0 Methoxymethylene CH3OCH (g, syn singlet) 144.8 134.4 ± 1.4 kJ/mol 44.0526 ± 0.0017 19527-10-7*22 Glycolaldehyde HC(O)CH2OH (g, anti-anti) -292.1 -304.7 ± 1.7 kJ/mol 60.0520 ± 0.0017 141-46-8*21 Glycolaldehyde HC(O)CH2OH (g, gauche-anti) -290.4 -302.8 ± 1.7 kJ/mol 60.0520 ± 0.0017 141-46-8*31 Glycolaldehyde HC(O)CH2OH (g, anti-syn) -283.8 -296.6 ± 1.7 kJ/mol 60.0520 ± 0.0017 141-46-8*22 Dioxiranylidene anion [C(OO)]- (g, ?) -110.2 -109.7 ± 3.0 kJ/mol 44.01005 ± 0.00100 *138832-58-3*0 Methyl acetate CH3C(O)OCH3 (l) -445.59 ± 0.56 kJ/mol 74.0785 ± 0.0025 79-20-9*500 Carbon dication [C]+2 (g) 4150.462 4155.609 ± 0.040 kJ/mol 12.00960 ± 0.00080 16092-61-8*0 1-Hydroxy-2-propanone CH3C(O)CH2OH (g, anti-anti) -340.5 -360.3 ± 1.7 kJ/mol 74.0785 ± 0.0025 116-09-6*21 1-Hydroxy-2-propanone CH3C(O)CH2OH (g, gauche-anti) -337.9 -356.1 ± 1.7 kJ/mol 74.0785 ± 0.0025 116-09-6*31 1-Hydroxy-2-propanone CH3C(O)CH2OH (g, anti-syn) -329.6 -349.6 ± 1.7 kJ/mol 74.0785 ± 0.0025 116-09-6*22 Isocyanogen bromide BrNC (g) 341.2 335.5 ± 3.5 kJ/mol 105.9214 ± 0.0013 65997-98-0*0 Cycloprop-2-enylide [CH(CHCH)]- (g) 514.9 511.9 ± 2.2 kJ/mol 39.0565 ± 0.0024 20829-57-6*0 Methoxyoxomethyl CH3OCO (g, syn-staggered) -151.7 -160.8 ± 1.5 kJ/mol 59.0440 ± 0.0017 16481-04-2*2 Hydrogen chloride HCl (aq, 2439 H2O) -166.712 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*951 Dioxymethylidyne cation [COO]+ (g, doublet) 1436.6 1439.0 ± 2.7 kJ/mol 44.00895 ± 0.00100 *791121-04-5*2 Hydroxyoxoammoniumyl [HONO]+ (g, trans) 984.1 977.7 ± 1.8 kJ/mol 47.01293 ± 0.00061 80371-48-8*1 Isocyanogen iodide INC (g) 341.7 341.9 ± 4.9 kJ/mol 152.92191 ± 0.00080 66004-32-8*0 Isocyanogen iodide anion [INC]- (g) 123.0 125.2 ± 9.3 kJ/mol 152.92246 ± 0.00080 *66004-32-8*0 Propionic acid CH3CH2C(O)OH (cr,l) -505.37 -509.52 ± 0.17 kJ/mol 74.0785 ± 0.0025 79-09-4*500 Ammonium hydroxide NH4OH (aq, 1 H2O) -363.82 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*801 Ethylene glycol (CH2OH)2 (cr,l) -448.63 -455.15 ± 0.37 kJ/mol 62.0678 ± 0.0018 107-21-1*500 Oxalic acid (C(O)OH)2 (cr) -819.55 -829.64 ± 0.42 kJ/mol 90.0349 ± 0.0020 144-62-7*500 Dimethylamine (CH3)2NH (l) -42.59 ± 0.56 kJ/mol 45.0837 ± 0.0017 124-40-3*500 Ammonium hydroxide NH4OH (aq, 2 H2O) -364.67 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*803 Tetrafluorohydrazine NF2NF2 (g) -13.4 -22.5 ± 1.4 kJ/mol 104.00709 ± 0.00014 10036-47-2*0 (E)-2-Iminoethylium [CH2CHNH]+ (g, anti-triplet) 1148.7 1138.9 ± 3.3 kJ/mol 42.0594 ± 0.0016 91127-33-2*12 1-Iminoethylium [CH3CNH]+ (g, singlet) 833.7 823.2 ± 3.0 kJ/mol 42.0594 ± 0.0016 *128365-64-0*2 1-Iminoethanide [CH3CNH]- (g, anti) 185.7 175.3 ± 3.2 kJ/mol 42.0604 ± 0.0016 *128365-65-1*2 1-Iminoethylium [CH3CNH]+ (g, anti-triplet) 1342.2 1333.3 ± 3.9 kJ/mol 42.0594 ± 0.0016 *128365-64-0*12 Nitrous acid anion [HONO]- (g, cis) -105.84 -110.46 ± 0.78 kJ/mol 47.01403 ± 0.00061 256393-36-9*2 N-Methylenemethaniminium [CH2NCH2]+ (g, singlet) 904.4 893.4 ± 3.1 kJ/mol 42.0594 ± 0.0016 88333-01-1*2 2-Hydroxyethenyl CHCHOH (g, cis-cis) 143.87 137.31 ± 0.99 kJ/mol 43.0446 ± 0.0016 108665-16-3*11 (Methylimino)methanide [CH3NCH]- (g, trans) 223.0 212.2 ± 3.2 kJ/mol 42.0604 ± 0.0016 *64709-60-0*1 Ammonium hydroxide NH4OH (aq, 3 H2O) -365.13 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*805 2-Aminoethenylium [CHCHNH2]+ (g, anti triplet) 1110.6 1099.5 ± 2.4 kJ/mol 42.0594 ± 0.0016 64724-21-6*12 2-Hydroxyethenyl CHCHOH (g, trans-trans) 147.2 140.9 ± 1.2 kJ/mol 43.0446 ± 0.0016 108665-16-3*22 2-Aminoethenyl anion [CHCHNH2]- (g, anti) 230.2 219.3 ± 2.6 kJ/mol 42.0604 ± 0.0016 *64724-21-6*2 Aziridine NH(CH2CH2) (cr,l) 92.36 ± 0.86 kJ/mol 43.0678 ± 0.0016 151-56-4*500 2-Aziridinylium [NH(CHCH2)]+ (g, singlet) 1010.9 998.9 ± 3.3 kJ/mol 42.0594 ± 0.0016 *91127-35-4*2 2-Aziridinide [NH(CHCH2)]- (g, anti) 316.2 304.1 ± 3.4 kJ/mol 42.0604 ± 0.0016 111127-93-6*2 2-Aziridinyl NH(CHCH2) (g, anti) 364.6 352.4 ± 2.1 kJ/mol 42.0599 ± 0.0016 *23838-09-7*2 2-Aziridinylium [NH(CHCH2)]+ (g, anti-triplet) 1305.0 1293.3 ± 4.1 kJ/mol 42.0594 ± 0.0016 *91127-35-4*12 Trimethylamine (CH3)3N (l) -48.26 ± 0.87 kJ/mol 59.1103 ± 0.0025 75-50-3*500 2-Hydroxyethenyl CHCHOH (g, cis-trans) 150.6 144.5 ± 1.6 kJ/mol 43.0446 ± 0.0016 108665-16-3*12 Cyanogen anion [NCCN]- (g) 281.5 284.7 ± 2.2 kJ/mol 52.0354 ± 0.0016 11118-88-0*0 Diisocyanogen cation [CNNC]+ (g, trans) 1825.3 1828.1 ± 3.2 kJ/mol 52.0343 ± 0.0016 *78800-21-2*1 Dioxymethylidyne cation [(C)(OO)]+ (g, vdW quartet) 1388.2 1391.7 ± 3.2 kJ/mol 44.00895 ± 0.00100 *791121-04-5*101 Cyanoaminyliumyl [NCN]+ (g) 1672.4 1673.7 ± 2.6 kJ/mol 40.02363 ± 0.00081 316122-03-9*0 Cyanoamidogen anion [NCN]- (g) 211.89 211.82 ± 0.60 kJ/mol 40.02473 ± 0.00081 189879-95-6*0 Oxygen atom hexacation [O]+6 (g) 42035.28 42037.14 ± 0.12 kJ/mol 15.99611 ± 0.00030 14158-22-6*0 Cyanoaminylium [HNCN]+ (g, singlet) 1460.2 1458.0 ± 1.9 kJ/mol 41.03157 ± 0.00082 205443-18-1*2 Carbon dioxide anion [CO2]- (g) -340.6 -340.1 ± 2.2 kJ/mol 44.01005 ± 0.00100 14485-07-5*0 Diazomethanide [HCNN]- (g, triplet) 479.8 478.3 ± 1.8 kJ/mol 41.03267 ± 0.00082 100840-43-5*1 Methanol dimer (CH3OH)2 (g) -398.3 -419.0 ± 1.4 kJ/mol 64.0837 ± 0.0018 42845-44-3*0 Cyclopropenylidene anion [C(CHCH)]- (g) 544.2 543.8 ± 2.2 kJ/mol 38.0485 ± 0.0024 *16165-40-5*0 Bicyclo[1.1.0]buta-1,3-dien-4-ylium-2-yl [C(CC)C]+ (g) 2087.7 2097.5 ± 2.3 kJ/mol 48.0423 ± 0.0032 289679-91-0*0 1H-Diazirin-3-ylium [HN(NC)]+ (g, triplet) 1640.4 1638.1 ± 2.0 kJ/mol 41.03157 ± 0.00082 735234-64-7*1 1H-diazirin-3-ide [HN(NC)]- (g, triplet) 655.3 652.1 ± 2.1 kJ/mol 41.03267 ± 0.00082 *735234-64-7*1 1H-Diazirin-3-yl HN(NC) (g) 618.7 615.8 ± 1.6 kJ/mol 41.03212 ± 0.00082 324529-57-9*0 Peroxyhypochlorite [ClOO]- (g) -252.78 -251.75 ± 0.34 kJ/mol 67.4520 ± 0.0011 224299-14-3*0 Chloryl ion [OClO]+ (g) 1100.26 1097.60 ± 0.53 kJ/mol 67.4510 ± 0.0011 25052-55-5*0 Cyanamide NH2CN (cr) 59.04 ± 0.52 kJ/mol 42.04006 ± 0.00082 420-04-2*500 Dihydrogen H2 (g, para) -0.000 -0.058 ± 0.000 kJ/mol 2.01588 ± 0.00014 1333-74-0*2 Bicyclo[1.1.0]buta-1,3-dien-2-yl anion [C(CC)C]- (g) 803.1 810.7 ± 1.8 kJ/mol 48.0433 ± 0.0032 289679-89-6*0 Methylenediazeniumide HCNNH (g) 375.2 368.7 ± 1.9 kJ/mol 42.04006 ± 0.00082 24153-51-3*0 Methylidynehydrazinium-1-yl [HCNNH]+ (g) 1251.8 1245.8 ± 1.9 kJ/mol 42.03951 ± 0.00082 160951-16-6*0 (Iminomethyl)imidogen HNCHN (g, anti-triplet) 420.1 413.1 ± 2.9 kJ/mol 42.04006 ± 0.00082 87570-07-8*11 Diazomethyliumyl [CNN]+ (g) 1639.6 1640.8 ± 3.1 kJ/mol 40.02363 ± 0.00081 307495-90-5*0 Diazomethylene anion [CNN]- (g) 407.0 407.1 ± 2.4 kJ/mol 40.02473 ± 0.00081 205498-92-6*0 3H-Diazirin-3-ylidene C(NN) (g) 579.1 579.5 ± 2.7 kJ/mol 40.02418 ± 0.00081 253308-70-2*0 Tetrafluorohydrazine cation [NF2NF2]+ (g, trans) 1129.2 1122.5 ± 2.5 kJ/mol 104.00654 ± 0.00014 37366-75-9*1 Ammonium hydroxide NH4OH (aq, 4 H2O) -365.43 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*807 Hydrogen fluoride HF (aq, 50 H2O) -321.95 ± 0.10 kJ/mol 20.006343 ± 0.000070 7664-39-3*822 Ethynylaminylium [HCCNH]+ (g, triplet) 1277.8 1277.4 ± 2.6 kJ/mol 40.0435 ± 0.0016 103835-08-1*1 Chloromethyliumylidene [CCl]+ (g) 1282.8 1285.8 ± 2.4 kJ/mol 47.4629 ± 0.0012 69773-94-0*0 Chloromethylidyne anion [CCl]- (g) 319.8 323.6 ± 2.5 kJ/mol 47.4639 ± 0.0012 117129-77-8*0 (Z)-Diazene anion [HNNH]- (g, cis) 280.0 273.3 ± 2.0 kJ/mol 30.02991 ± 0.00020 *86631-37-0*0 Chlorodioxidanyl ClOO (g) 100.36 99.27 ± 0.34 kJ/mol 67.4515 ± 0.0011 17376-09-9*0 Carbon dioxide cation [CO2]+ (g, quartet) 1335.0 1335.5 ± 2.4 kJ/mol 44.00895 ± 0.00100 12181-61-2*1 Paraformaldehyde CH2O (cr, paraformaldehyde) -176.4 ± 1.5 kJ/mol 30.02598 ± 0.00087 30525-89-4*500 Peroxyhypochlorous acid cation [HOOCl]+ (g, trans) 1030.4 1024.6 ± 2.5 kJ/mol 68.4589 ± 0.0011 *67952-07-2*1 1,3-Butadiynyl anion [CCCC]- (g) 677.2 686.3 ± 1.1 kJ/mol 48.0433 ± 0.0032 59158-53-1*0 Poly(vinylchloride) CH2CHCl (s, poly) -84.6 -94.0 ± 1.3 kJ/mol 62.4979 ± 0.0018 9002-86-2*500 1,1-Dichloroethene CH2CCl2 (l) -23.43 ± 0.51 kJ/mol 96.9427 ± 0.0024 75-35-4*500 2-Cyclopropyn-1-ylidenemethyliumyl [CC(CC)]+ (g) 2239.7 2247.6 ± 2.3 kJ/mol 48.0423 ± 0.0032 289679-92-1*0 Hydrogen fluoride HF (aq, 55 H2O) -321.96 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*905 2-Propen-3-ylium-1-ylidyne [CHCHC]+ (g) 1791.2 1792.8 ± 2.6 kJ/mol 38.0474 ± 0.0024 161054-36-0*0 Peroxyhypochlorous acid anion [HOOCl]- (g, cis quartet) -32.2 -33.9 ± 2.6 kJ/mol 68.4600 ± 0.0011 *67952-08-3*2 Propenediylidene anion [CHCHC]- (g) 588.8 590.1 ± 2.3 kJ/mol 38.0485 ± 0.0024 *161054-36-0*0 Iodoform CHI3 (cr,l) 181.11 ± 0.60 kJ/mol 393.73205 ± 0.00081 75-47-8*500 Diiodomethane CH2I2 (l) 68.21 ± 0.58 kJ/mol 267.83552 ± 0.00081 75-11-6*590 Dichloromethane CH2Cl2 (l) -122.70 ± 0.36 kJ/mol 84.9320 ± 0.0020 75-09-2*590 Ammonium hydroxide NH4OH (aq, 10 H2O) -366.00 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*815 Tribromofluoromethane CBr3F (g) -97.9 -121.9 ± 1.4 kJ/mol 270.7211 ± 0.0031 353-54-8*0 Tribromochloromethane CBr3Cl (g) 86.7 63.9 ± 1.4 kJ/mol 287.1754 ± 0.0032 594-15-0*0 Tetrazete N(NNN) (g, D2h) 764.9 759.0 ± 1.8 kJ/mol 56.02696 ± 0.00028 42851-09-2*0 Difluoromethylene anion [CF2]- (g) -211.16 -209.98 ± 0.58 kJ/mol 50.00805 ± 0.00080 66212-40-6*0 Fluoromethylidyne anion [CF]- (g) 200.8 204.3 ± 1.9 kJ/mol 31.00965 ± 0.00080 33412-12-3*0 Hydrogen fluoride HF (aq, 23 H2O) -321.85 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*903 Tetraazatetrahedrane N(N(N)N) (g, Td) 763.7 757.3 ± 1.7 kJ/mol 56.02696 ± 0.00028 12596-63-3*0 Ammonium hydroxide NH4OH (aq, 20 H2O) -366.20 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*818 Difluorovinylidene CCF2 (g) 129.4 130.6 ± 2.2 kJ/mol 62.0182 ± 0.0016 41895-33-4*0 Fluoroethynylium [CCF]+ (g) 1536.5 1541.2 ± 2.3 kJ/mol 43.0193 ± 0.0016 268566-69-4*0 2-Oxo-1-ethylium-1-yl [HCC(O)H]+ (g, anti-quartet) 1289.4 1286.0 ± 2.5 kJ/mol 42.0361 ± 0.0016 214464-96-7*11 Dioxohydrazine ONNO (g, cis) 172.90 171.13 ± 0.14 kJ/mol 60.01228 ± 0.00062 16824-89-8*2 Oxygen difluoride cation [FOF]+ (g) 1292.10 1289.58 ± 0.66 kJ/mol 53.99566 ± 0.00030 39432-25-2*0 Oxoethylidene anion [HCC(O)H]- (g, anti-gauche) 86.9 83.6 ± 2.1 kJ/mol 42.0372 ± 0.0016 106543-38-8*1 Chloro(chlorooxy)methylene ClCOCl (g, trans singlet) 98. 101. ± 15. kJ/mol 98.9155 ± 0.0020 479587-31-0*11 Chlorooxomethylium [ClCO]+ (g) 783.7 783.9 ± 2.2 kJ/mol 63.4623 ± 0.0012 38264-03-8*0 2-Iodoethanol ICH2CH2OH (l) -207.2 ± 2.4 kJ/mol 171.9650 ± 0.0017 624-76-0*590 1,3-Butadiyne cation [HCCCCH]+ (g) 1440.26 1442.12 ± 0.55 kJ/mol 50.0581 ± 0.0032 55468-55-8*0 Carbon monoxide anion [CO]- (g) 30.0 33.7 ± 2.3 kJ/mol 28.01065 ± 0.00085 12539-63-8*0 1,3,5-Hexatriynide [CCCCCCH]- (g) 635.6 644.1 ± 2.3 kJ/mol 73.0727 ± 0.0048 85905-65-3*0 Carbon suboxide cation [OCCCO]+ (g) 928.8 932.3 ± 1.1 kJ/mol 68.0304 ± 0.0025 151528-67-5*0 Carbon suboxide anion [OCCCO]- (g) -131.1 -127.7 ± 2.5 kJ/mol 68.0314 ± 0.0025 109362-94-9*0 Benzene anion [C6H6]- (g) 209.1 197.2 ± 1.2 kJ/mol 78.1124 ± 0.0048 34562-85-1*0 Acetonitrile CH3CN (cr,l) 40.63 ± 0.22 kJ/mol 41.0520 ± 0.0016 75-05-8*500 Ammonium hydroxide NH4OH (aq, 50 H2O) -366.32 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*822 o-Benzyne C6H4 (g, triplet) 625.8 616.4 ± 1.1 kJ/mol 76.0960 ± 0.0048 462-80-6*1 m-Benzyne C6H4 (g) 527.5 519.0 ± 1.2 kJ/mol 76.0960 ± 0.0048 1828-89-3*0 p-Benzyne cation [C6H4]+ (g) 1423.7 1416.4 ± 2.0 kJ/mol 76.0954 ± 0.0048 121058-09-1*0 p-Benzyne C6H4 (g) 587.1 577.7 ± 1.2 kJ/mol 76.0960 ± 0.0048 3355-34-8*0 Deuterium hydride HD (g) 0.328 0.319 ± 0.000 kJ/mol 3.022042 ± 0.000070 13983-20-5*0 Toluene C6H5CH3 (l) 19.80 12.04 ± 0.31 kJ/mol 92.1384 ± 0.0056 108-88-3*500 Carbon monoxide CO (g, triplet) 465.584 469.291 ± 0.026 kJ/mol 28.01010 ± 0.00085 630-08-0*1 Dihydrogen cation [H2]+ (g, ortho) 1489.060 1488.480 ± 0.000 kJ/mol 2.01533 ± 0.00014 12184-90-6*1 Cyclobutane CH2(CH2CH2CH2) (l) 3.90 ± 0.38 kJ/mol 56.1063 ± 0.0032 287-23-0*590 Cyclopentadienylium [CH(CHCHCHCH)]+ (g) 1088.72 1075.85 ± 0.80 kJ/mol 65.0927 ± 0.0040 29661-18-5*0 Ammonium hydroxide NH4OH (aq, 100 H2O) -366.36 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*828 Cycloheptene CH2(CHCHCH2CH2CH2CH2) (cr,l) -25.1 -46.2 ± 1.7 kJ/mol 96.1702 ± 0.0057 628-92-2*500 Cycloheptatriene CH2(CHCHCHCHCHCH) (cr,l) 154.47 145.68 ± 0.92 kJ/mol 92.1384 ± 0.0056 544-25-2*500 Methylcyclopropane CH3CH(CH2CH2) (l) 1.92 ± 0.59 kJ/mol 56.1063 ± 0.0032 594-11-6*590 Phenylethene C6H5CHCH2 (cr,l) 104.49 ± 0.47 kJ/mol 104.1491 ± 0.0064 100-42-5*500 Difluorodioxidanium [FOOF]+ (g, trans) 1283.7 1279.2 ± 2.3 kJ/mol 69.99506 ± 0.00060 *7783-44-0*1 Benzonitrile C6H5CN (cr,l) 161.18 163.54 ± 0.90 kJ/mol 103.1213 ± 0.0056 100-47-0*500 Isocyanobenzene C6H5NC (g) 321.0 307.1 ± 1.7 kJ/mol 103.1213 ± 0.0056 931-54-4*0 Isoindene C6H4(CHCH2CH) (g) 269.9 246.5 ± 1.9 kJ/mol 116.1598 ± 0.0072 270-53-1*0 Dioxygen difluoride OOF2 (g) 75.1 71.7 ± 3.6 kJ/mol 69.99561 ± 0.00060 183051-89-0*0 Phenol C6H5OH (cr,l) -146.15 -161.99 ± 0.64 kJ/mol 94.1112 ± 0.0048 108-95-2*500 Anisole C6H5OCH3 (l) -117.51 ± 0.61 kJ/mol 108.1378 ± 0.0056 100-66-3*500 Benzaldehyde C6H5C(O)H (cr,l) -85.59 -86.66 ± 0.90 kJ/mol 106.1219 ± 0.0056 100-52-7*500 Dioxohydrazine ONNO (g) 172.90 171.13 ± 0.14 kJ/mol 60.01228 ± 0.00062 16824-89-8*0 Acetophenone C6H5C(O)CH3 (cr,l) -139.3 ± 1.1 kJ/mol 120.1485 ± 0.0064 98-86-2*500 1-Phenylethenol C6H5C(OH)CH2 (g) -8.7 -32.5 ± 2.0 kJ/mol 120.1485 ± 0.0064 4383-15-7*0 p-Tolualdehyde CH3C6H4C(O)H (cr, l, para) -125.8 ± 1.3 kJ/mol 120.1485 ± 0.0064 104-87-0*500 Perchloryl cation [OCl(O)O]+ (g) 1252.1 1246.4 ± 2.5 kJ/mol 83.4504 ± 0.0013 23594-88-9*0 o-Tolualdehyde CH3C6H4C(O)H (cr, l, ortho) -118.9 ± 1.1 kJ/mol 120.1485 ± 0.0064 529-20-4*500 Tetraoxodinitrogen cation [O2NNO2]+ (g) 1030.6 1025.1 ± 2.6 kJ/mol 92.0105 ± 0.0012 64476-91-1*0 Ammonium hydroxide NH4OH (aq, 500 H2O) -366.38 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*833 Fluorobenzene anion [C6H5F]- (g) -15.3 -27.1 ± 1.6 kJ/mol 96.1029 ± 0.0048 34561-55-2*0 Hexafluorobenzene anion [C6F6]- (g) -992.7 -995.0 ± 3.5 kJ/mol 186.0552 ± 0.0048 37551-90-9*0 Tetraoxidanyl HOOOO (g, cis) 53.0 46.0 ± 5.1 kJ/mol 65.0055 ± 0.0012 69696-93-1*2 m-Chlorophenylium [C6H4Cl]+ (g) 1161.7 1151.6 ± 2.6 kJ/mol 111.5481 ± 0.0049 127983-85-1*0 Dihydrogen H2 (g, ortho) 1.417 0.019 ± 0.000 kJ/mol 2.01588 ± 0.00014 1333-74-0*1 p-Chlorophenylium [C6H4Cl]+ (g) 1149.0 1139.5 ± 2.5 kJ/mol 111.5481 ± 0.0049 42766-43-8*0 o-Chlorophenylium [C6H4Cl]+ (g) 1168.3 1159.0 ± 2.5 kJ/mol 111.5481 ± 0.0049 137963-70-3*0 Ammonia anion [NH3]- (g) 94.3 87.3 ± 2.4 kJ/mol 17.03111 ± 0.00022 37353-00-7*0 Trichlorine Cl3 (g) 125.3 125.8 ± 2.0 kJ/mol 106.3581 ± 0.0027 11094-65-8*0 Iodobenzene cation [C6H5I]+ (g) 1023.62 1008.19 ± 0.99 kJ/mol 204.0078 ± 0.0048 38406-85-8*0 Nitrobenzene C6H5N(O)O (cr,l) 7.4 ± 1.3 kJ/mol 123.1094 ± 0.0049 98-95-3*500 Furan O(CHCHCHCH) (cr,l) -62.55 -61.94 ± 0.60 kJ/mol 68.0740 ± 0.0032 110-00-9*500 Hydroxymethoxy CH2(OH)O (g) -159.58 -169.43 ± 0.84 kJ/mol 47.0333 ± 0.0010 72144-78-6*0 Pyridine N(CHCHCHCHCH) (cr,l) 102.23 100.20 ± 0.38 kJ/mol 79.0999 ± 0.0040 110-86-1*500 Hydrogen iodide HI (aq) -56.824 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*800 Hydraziniumyl [NH2NH2]+ (g) 886.7 873.3 ± 2.0 kJ/mol 32.04469 ± 0.00031 20771-51-1*0 Nitromethane CH3N(O)O (cr,l) -113.95 -112.76 ± 0.39 kJ/mol 61.0401 ± 0.0010 75-52-5*500 Hydrogen difluoride cation [FHF]+ (g, triplet ?) 1241. 1238. ± 17. kJ/mol 39.004198 ± 0.000070 126950-54-7*1 Nitroethane CH3CH2N(O)O (cr,l) -141.89 -144.10 ± 0.57 kJ/mol 75.0666 ± 0.0017 79-24-3*500 Isodiazene anion [NNH2]- (g) 380.9 374.1 ± 2.1 kJ/mol 30.02991 ± 0.00020 *63986-30-1*0 Glycine NH2CH2C(O)OH (aq, undissoc) -514.22 ± 0.20 kJ/mol 75.0666 ± 0.0017 56-40-6*1000 Oxadiazirine cation [O(NN)]+ (g) 1509.9 1507.2 ± 2.4 kJ/mol 44.01233 ± 0.00033 *227934-45-4*0 Hydroxymethyleneoxonium [CH2OOH]+ (g) 792.97 782.83 ± 0.62 kJ/mol 47.0328 ± 0.0010 77144-12-8*0 Ethyl hydroperoxide CH3CH2OOH (cr,l) -209. ± 20. kJ/mol 62.0678 ± 0.0018 3031-74-1*500 2,2,4-Trimethylpentane (CH3)2CHCH2C(CH3)3 (cr,l) -224.2 -258.6 ± 1.5 kJ/mol 114.2285 ± 0.0065 540-84-1*500 Norbornadiene (CHCH)(CHCH2CH)(CHCH) (l) 206.3 ± 1.6 kJ/mol 92.1384 ± 0.0056 121-46-0*500 2,3-Butanedione CH3C(O)C(O)CH3 (cr,l) -365.56 ± 0.53 kJ/mol 86.0892 ± 0.0033 431-03-8*500 Succinic acid (CH2C(O)OH)2 (g) -801.1 -823.3 ± 2.7 kJ/mol 118.0880 ± 0.0034 110-15-6*0 1,2-Diiodoethane CH2ICH2I (g) 87.84 73.18 ± 0.90 kJ/mol 281.8621 ± 0.0016 624-73-7*0 1,2-Diiodoethane CH2ICH2I (cr,l) 9.31 ± 0.60 kJ/mol 281.8621 ± 0.0016 624-73-7*500 2-Butanone CH3CH2C(O)CH3 (cr,l) -267.71 -273.20 ± 0.79 kJ/mol 72.1057 ± 0.0033 78-93-3*500 Trioxirane O(OO) (g) 272.5 269.9 ± 1.3 kJ/mol 47.99820 ± 0.00090 153851-84-4*0 Acrolein cation [CH2CHCHO]+ (g, trans) 920.02 909.88 ± 0.79 kJ/mol 56.0627 ± 0.0024 84005-05-0*1 Acrolein anion [CH2CHCHO]- (g, cis) -71.8 -81.9 ± 3.1 kJ/mol 56.0638 ± 0.0024 23555-87-5*2 Acrolein CH2CHCHO (cr,l) -95.57 ± 0.96 kJ/mol 56.0633 ± 0.0024 107-02-8*500 1-Oxo-2-propenylium [CH2CHCO]+ (g, singlet) 772.8 766.0 ± 3.0 kJ/mol 55.0548 ± 0.0024 35335-83-2*2 1-Oxo-2-propenide [CH2CHCO]- (g, I, trans) 50.7 46.0 ± 2.6 kJ/mol 55.0559 ± 0.0024 78944-75-9*1 Chlorine chlorite ClOClO (g, cis) 177.4 175.1 ± 2.2 kJ/mol 102.9042 ± 0.0019 105206-44-8*2 3-Oxo-1-propenylium [CHCHCHO]+ (g, anti-cis-triplet) 1197.7 1192.0 ± 3.4 kJ/mol 55.0548 ± 0.0024 101705-90-2*121 NON cation [NON]+ (g) 1444.0 1444.2 ± 2.8 kJ/mol 44.01233 ± 0.00033 *227934-46-5*0 Ethenedione anion [OCCO]- (g) -149.7 -147.1 ± 1.7 kJ/mol 56.0207 ± 0.0017 77783-15-4*0 Urea NH2C(O)NH2 (cr,l) -317.73 -333.33 ± 0.12 kJ/mol 60.05534 ± 0.00091 57-13-6*500 1,2-Butadienylium [CH3CHCCH]+ (g, triplet) 1315.5 1307.5 ± 1.7 kJ/mol 53.0820 ± 0.0032 *65114-67-2*1 Trioxidanyl HOOO (g) 25.36 23.27 ± 0.13 kJ/mol 49.00614 ± 0.00090 12500-78-6*0 Formamide CH(O)NH2 (cr,l) -251.05 ± 0.28 kJ/mol 45.04066 ± 0.00088 75-12-7*500 Aminohydroxymethylene NH2COH (g, Cs-triplet) 217.2 208.7 ± 3.0 kJ/mol 45.04066 ± 0.00088 160720-48-9*11 Acetamide CH3C(O)NH2 (cr,l) -315.89 ± 0.53 kJ/mol 59.0672 ± 0.0017 60-35-5*500 Acrylonitrile CH2CHCN (g, triplet) 446.5 441.1 ± 1.7 kJ/mol 53.0627 ± 0.0024 107-13-1*2 Acrylonitrile CH2CHCN (cr,l) 146.53 154.19 ± 0.73 kJ/mol 53.0627 ± 0.0024 107-13-1*500 Isocyanoethene CH2CHNC (g, triplet) 544.2 539.3 ± 1.8 kJ/mol 53.0627 ± 0.0024 14668-82-7*2 NON anion [NON]- (g) 495.3 492.8 ± 2.5 kJ/mol 44.01343 ± 0.00033 *227934-47-6*0 1-Isocyanoethylidene CH3CNC (g) 527.9 523.2 ± 1.1 kJ/mol 53.0627 ± 0.0024 *498544-34-6*0 Carbonate [OC(O)O]-2 (g) -225.2 -228.4 ± 2.5 kJ/mol 60.0100 ± 0.0012 3812-32-6*0 1,3-Butadienylium [CH2CHCHCH]+ (g, triplet) 1255.9 1246.6 ± 2.3 kJ/mol 53.0820 ± 0.0032 86181-69-3*1 Carbon dioxide CO2 (aq, undissoc) -412.868 ± 0.018 kJ/mol 44.00950 ± 0.00100 124-38-9*1000 1,3-Dioxolan-2-one C(O)(OCH2CH2O) (cr,l) -581.53 ± 0.36 kJ/mol 88.0621 ± 0.0026 96-49-1*500 Hydrazine NH2NH2 (cr,l) 57.30 50.74 ± 0.18 kJ/mol 32.04524 ± 0.00031 302-01-2*500 Tetraoxygen O4 (g, C2h triplet) 104.4 102.4 ± 3.5 kJ/mol 63.9976 ± 0.0012 12596-83-7*11 Vinylacetylene CH2CHCCH (cr,l) 266.5 ± 2.1 kJ/mol 52.0746 ± 0.0032 689-97-4*500 Nitric acid trihydrate (HON(O)O)(H2O)3 (cr,l) -1061.98 -1055.13 ± 0.20 kJ/mol 117.0587 ± 0.0019 13444-83-2*500 Oxygen difluoride anion [FOF]- (g) -202.1 -201.9 ± 2.7 kJ/mol 53.99675 ± 0.00030 *7783-41-7*0 Hydrogen peroxide HOOH (cr,l) -193.105 -187.288 ± 0.077 kJ/mol 34.01468 ± 0.00062 7722-84-1*500 Dihydrogen cation [H2]+ (g, para) 1488.364 1488.480 ± 0.000 kJ/mol 2.01533 ± 0.00014 12184-90-6*2 Vinylvinylidene CH2CHCHC (g, triplet, trans) 690.5 684.4 ± 2.6 kJ/mol 52.0746 ± 0.0032 148759-16-4*11 Isocyanic fluoride FNC (g) 300.9 302.7 ± 1.8 kJ/mol 45.01584 ± 0.00080 16992-26-0*0 Nitric acid monohydrate (HON(O)O)(H2O) (cr,l) -479.09 -472.59 ± 0.18 kJ/mol 81.0282 ± 0.0012 13444-82-1*500 1-Buten-3-ynylium [HCCCHCH]+ (g, cis) 1483.2 1480.7 ± 1.6 kJ/mol 51.0661 ± 0.0032 84654-85-3*2 Hydrogen difluoride cation [(HF)(F)]+ (g, triplet) 1267.6 1265.4 ± 4.1 kJ/mol 39.004198 ± 0.000070 *126950-54-7*1 Ethynylene C2 (g, triplet) 827.207 833.912 ± 0.085 kJ/mol 24.0214 ± 0.0016 12070-15-4*1 1,3-Propanediyl CH2CH2CH2 (g, triplet C2) 320.3 308.5 ± 1.5 kJ/mol 42.0797 ± 0.0024 32458-33-6*12 2-Cyclopropen-1-ylidenemethylium [CHC(CHCH)]+ (g, triplet) 1433.2 1429.5 ± 1.9 kJ/mol 51.0661 ± 0.0032 112936-36-4*1 Ammonium hydroxide NH4OH (aq, 5000 H2O) -366.30 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*844 1,3-Cyclobutadien-1-ylium [C(CHCHCH)]+ (g, triplet) 1473.1 1468.5 ± 1.9 kJ/mol 51.0661 ± 0.0032 81913-77-1*1 1,3-Cyclobutadien-1-yl anion [C(CHCHCH)]- (g) 616.5 611.9 ± 2.1 kJ/mol 51.0672 ± 0.0032 154675-37-3*0 Iodine monochloride ICl (cr) -36.511 -35.537 ± 0.063 kJ/mol 162.35717 ± 0.00090 7790-99-0*510 Cyclobutenylium [CH2(CHCHCH)]+ (g) 1038.7 1025.6 ± 2.8 kJ/mol 53.0820 ± 0.0032 12316-90-4*0 Butyraldehyde CH3CH2CH2CHO (cr,l) -235.80 -239.32 ± 0.84 kJ/mol 72.1057 ± 0.0033 123-72-8*500 Peroxychlorous acid HOOClO (g, anti) 102.7 96.9 ± 2.4 kJ/mol 84.4588 ± 0.0013 177778-92-6*2 Dihydrogen fluoride (HF)(H) (g) -56.5 -54.2 ± 1.7 kJ/mol 21.01428 ± 0.00014 12592-22-2*2 Peroxynitrous acid HOONO (g) -5.74 -11.57 ± 0.35 kJ/mol 63.01288 ± 0.00091 14691-52-2*0 Trihydrogen H(HH) (g, 2p 2A2" Ry) 756.931 754.146 ± 0.015 kJ/mol 3.02382 ± 0.00021 12184-91-7*2 Dimethyl carbonate C(O)(OCH3)2 (cr,l) -608.58 ± 0.31 kJ/mol 90.0779 ± 0.0026 616-38-6*500 Disilicon cation [Si2]+ (g) 1352.3 1355.9 ± 2.4 kJ/mol 56.17045 ± 0.00060 12597-36-3*0 Dioxosilane cation [SiO2]+ (g) 946.3 946.2 ± 2.8 kJ/mol 60.08375 ± 0.00067 59458-81-0*0 Silicate [SiO2]- (g) -477.5 -478.2 ± 2.6 kJ/mol 60.08485 ± 0.00067 53095-83-3*0 Formic acid HC(O)OH (aq) -425.44 ± 0.45 kJ/mol 46.0254 ± 0.0010 64-18-6*800 Oxosilicate [SiO]- (g) -106.0 -104.8 ± 2.6 kJ/mol 44.08545 ± 0.00042 12503-59-2*0 Silicon carbide SiC (cr, beta-cubic) -71.9 -72.9 ± 1.4 kJ/mol 40.09620 ± 0.00085 409-21-2*502 Ammonium hydroxide NH4OH (aq, 10000 H2O) -366.25 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*850 Bicyclo[1.1.1]pentane-1,3-diyl C(CH2)3C (g, triplet) 783.4 766.2 ± 1.8 kJ/mol 66.1011 ± 0.0040 863892-18-6*1 Fluorosilylidyne anion [SiF]- (g) -139.0 -137.7 ± 1.8 kJ/mol 47.08445 ± 0.00030 11080-58-3*0 Chlorine hydride oxide HCl(O)(O)O (g) 163.9 154.0 ± 2.4 kJ/mol 84.4588 ± 0.0013 1027055-52-2*0 Silane cation [SiH4]+ (g) 1104.7 1097.5 ± 1.6 kJ/mol 32.11671 ± 0.00041 34826-51-2*0 Silylium [SiH3]+ (g) 989.66 984.08 ± 0.89 kJ/mol 31.10877 ± 0.00037 41753-67-7*0 Triiodine I3 (g) 153.4 149.4 ± 3.6 kJ/mol 380.713410 ± 0.000090 12596-31-5*0 Silylidyne anion [SiH]- (g) 250.0 251.2 ± 1.1 kJ/mol 29.09399 ± 0.00031 68865-96-3*0 Disilanylium [SiH3SiH2]+ (g) 981.5 970.2 ± 2.5 kJ/mol 61.21015 ± 0.00069 86860-82-4*0 1-Disilanylium-1-yl [SiH3SiH]+ (g) 1124.1 1116.5 ± 2.2 kJ/mol 60.20221 ± 0.00066 108492-64-4*0 Di-mu-hydrodihydrodisilicon cation [HSi(HSiHH)]+ (g, cis) 1194.4 1184.8 ± 3.4 kJ/mol 60.20221 ± 0.00066 *129970-82-7*2 Di-mu-hydrodihydrodisilicon anion [HSi(HSiHH)]- (g, cis) 296.7 289.2 ± 3.5 kJ/mol 60.20331 ± 0.00066 *129970-83-8*2 1-Ethenylium-1-yl [CCH2]+ (g) 1507.1 1507.1 ± 2.1 kJ/mol 26.0367 ± 0.0016 80541-07-7*0 Bromosyl bromide BrBrO (g) 180.4 164.6 ± 2.1 kJ/mol 175.8074 ± 0.0020 68322-97-4*0 Vinylcyclopentadienylium [CH2CHC(CHCHCHCH)]+ (g, singlet) 1076.9 1059.5 ± 3.7 kJ/mol 91.1299 ± 0.0056 146893-89-2*2 Ammonium hydroxide NH4OH (aq, 50000 H2O) -366.02 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*855 Ammonium hydroxide NH4OH (aq, 100000 H2O) -365.86 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*861 Hydrazoic acid cation [HNNN]+ (g) 1333.73 1328.06 ± 0.82 kJ/mol 43.02761 ± 0.00022 58852-14-5*0 Hydronium radical (H2O)(H) (g, vdW) -18.5 -21.5 ± 2.1 kJ/mol 19.02322 ± 0.00037 12168-76-2*100 Bromoniumyl [HBr]+ (g) 1098.16 1090.32 ± 0.12 kJ/mol 80.9114 ± 0.0010 12258-64-9*0 Nitrosyl nitrite anion [ONONO]- (g, t, t) -103.1 -106.2 ± 2.8 kJ/mol 76.01223 ± 0.00091 *122413-35-8*1 Hydrazoic acid anion [HNNN]- (g, trans) 309.1 302.8 ± 2.3 kJ/mol 43.02871 ± 0.00022 203264-98-6*1 2,4-Hexadiyne CH3CCCCCH3 (cr,l) 319.19 312.84 ± 0.95 kJ/mol 78.1118 ± 0.0048 2809-69-0*500 Hydrochlorate ion [HCl]- (g) -25.2 -24.2 ± 2.5 kJ/mol 36.46119 ± 0.00090 63099-75-2*0 Trimethylenecyclopropane (C3)(CH2)3 (g) 454.3 441.4 ± 1.8 kJ/mol 78.1118 ± 0.0048 3227-90-5*0 3,4-Bis(methylene)cyclobutene CH2(CCHCHC)CH2 (g) 355.6 341.1 ± 1.8 kJ/mol 78.1118 ± 0.0048 5291-90-7*0 1-Ethynylcyclobutene HCCC(CHCH2CH2) (g) 402.3 388.0 ± 1.8 kJ/mol 78.1118 ± 0.0048 813466-25-0*0 3-Methyl-1,2-pentadien-4-yne CH2CC(CH3)CCH (g) 414.7 403.5 ± 2.2 kJ/mol 78.1118 ± 0.0048 813466-14-7*0 Isoprene CH2C(CH3)CHCH2 (cr,l) 48.99 ± 0.69 kJ/mol 68.1170 ± 0.0040 78-79-5*500 Dioxodiazoxane ONONO (g, c, p) 125.7 120.4 ± 2.1 kJ/mol 76.01168 ± 0.00091 122413-35-8*3 1-Ethynyl-2-propyn-1-ylidene HCCCCCH (g, singlet C2v) 787.5 792.5 ± 2.1 kJ/mol 62.0694 ± 0.0040 882068-94-2*21 1-Ethynyl-2-propyn-1-ylidene HCCCCCH (g, singlet Cs) 796.1 801.0 ± 2.6 kJ/mol 62.0694 ± 0.0040 882068-94-2*22 1,3-Pentadiyne-1.5-diyl CH2CCCC (g) 783.8 787.4 ± 2.1 kJ/mol 62.0694 ± 0.0040 117992-81-1*0 1,3-Pentadiyne HCCCCCH3 (cr,l) 385.1 ± 5.0 kJ/mol 64.0853 ± 0.0040 4911-55-1*500 Penta-1,4-diyn-3-ide [CHCCHCCH]- (g, syn) 443.9 443.3 ± 3.2 kJ/mol 63.0779 ± 0.0040 553662-77-4*1 Propane cation [CH3CH2CH3]+ (g) 974.7 954.6 ± 1.7 kJ/mol 44.0951 ± 0.0025 34479-70-4*0 1-Aminoethylium [CH3CHNH2]+ (g) 683.4 664.8 ± 2.3 kJ/mol 44.0752 ± 0.0017 *30208-36-7*0 1-Propanamine CH3CH2CH2NH2 (cr,l) -93.76 -101.37 ± 0.40 kJ/mol 59.1103 ± 0.0025 107-10-8*500 2-Propanamine CH3CH(CH3)NH2 (cr,l) -101.52 -112.14 ± 0.52 kJ/mol 59.1103 ± 0.0025 75-31-0*500 Naphthalene C6H4(C4H4) (cr,l) 94.71 75.13 ± 0.55 kJ/mol 128.1705 ± 0.0080 91-20-3*500 Azide [NNN]- (aq) 272.69 ± 0.47 kJ/mol 42.02077 ± 0.00021 14343-69-2*800 Methylamine CH3NH2 (l) -45.18 ± 0.44 kJ/mol 31.05714 ± 0.00088 74-89-5*500 1-Propenylium [CH3CHCH]+ (g, cis) 1231.9 1221.6 ± 1.7 kJ/mol 41.0713 ± 0.0024 50457-58-4*2 Biphenyl C6H5C6H5 (cr,l) 121.6 97.2 ± 1.1 kJ/mol 154.2078 ± 0.0096 92-52-4*500 Biphenyl C6H5C6H5 (cr) 121.6 97.2 ± 1.1 kJ/mol 154.2078 ± 0.0096 92-52-4*520 1-Propenylide [CH3CHCH]- (g, cis) 204.0 192.7 ± 1.8 kJ/mol 41.0723 ± 0.0024 65887-20-9*2 Aniline C6H5NH2 (cr,l) 37.29 31.03 ± 0.63 kJ/mol 93.1265 ± 0.0048 62-53-3*500 Dihelium He2 (g, triplet) 1733.310 1729.576 ± 0.018 kJ/mol 8.0052040 ± 0.0000040 12184-98-4*1 Dihydrohelium cation [HeHH]+ (g) 1467.27 1461.99 ± 0.44 kJ/mol 6.01793 ± 0.00014 12500-88-8*0 Neon cation Ne+ (g) 2080.662 2080.769 ± 0.000 kJ/mol 20.17915 ± 0.00060 14782-23-1*0 Pyruvic acid CH3C(O)C(O)OH (cr,l) -588.44 ± 0.73 kJ/mol 88.0621 ± 0.0026 127-17-3*500 Disulfur cation [S2]+ (g) 1031.49 1032.08 ± 0.32 kJ/mol 64.1315 ± 0.0120 12597-02-3*0 Sulfur trioxide OS(O)O (l) -440.87 ± 0.30 kJ/mol 80.0642 ± 0.0061 7446-11-9*590 Cyclic thiozone S(SS) (g) 168.5 166.7 ± 2.3 kJ/mol 96.1980 ± 0.0180 *12597-03-4*0 Trifluoroammoniumyl [NF3]+ (g) 1093.4 1087.3 ± 2.3 kJ/mol 71.001401 ± 0.000070 54384-83-7*0 Hydroxylamine NH2OH (aq, undissoc) -97.0 ± 2.2 kJ/mol 33.02996 ± 0.00037 7803-49-8*1000 Sulfanylium [SH]+ (g) 1148.36 1148.36 ± 0.19 kJ/mol 33.0734 ± 0.0060 12273-42-6*0 Dioxiranylidene cation [C(OO)]+ (g) 1409.1 1410.3 ± 2.6 kJ/mol 44.00895 ± 0.00100 *138832-57-2*0 Sulfuric acid OS(O)(OH)2 (aq, 70 H2O) -887.09 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*824 Trifluorine F3 (g) 80.9 82.1 ± 2.5 kJ/mol 56.9952096 ± 0.0000015 73455-86-4*0 Ethylideneoxoniumyloxy [CH3CHOO]+ (g, anti) 950.9 938.4 ± 2.2 kJ/mol 60.0514 ± 0.0017 1427752-17-7*1 n-Heptane CH3(CH2)5CH3 (cr,l) -201.46 -223.91 ± 0.44 kJ/mol 100.2019 ± 0.0057 142-82-5*500 Dioxidanyl dimer (HOO)2 (g, triplet) -8.28 -17.85 ± 0.50 kJ/mol 66.0135 ± 0.0012 240125-82-0*1 Sulfur hydroxide oxide cation [OHS(O)(O)O]+ (g, eclipsed) 658.6 647.8 ± 3.4 kJ/mol 97.0710 ± 0.0061 *12337-07-4*2 Sulfurous acid S(O)(OH)2 (g) -511.31 -520.82 ± 0.89 kJ/mol 82.0801 ± 0.0061 7782-99-2*0 Sulfurous acid S(O)(OH)2 (aq, undissoc) -606.49 ± 0.14 kJ/mol 82.0801 ± 0.0061 7782-99-2*1000 Hydrogen sulfite [OS(OH)O]- (aq, undissoc) -631.83 ± 0.15 kJ/mol 81.0727 ± 0.0061 15181-46-1*1000 Sulfur dioxide - hydroxyl complex (OH)(OSO) (g, vdW) -266.0 -268.1 ± 2.2 kJ/mol 81.0721 ± 0.0061 *32750-86-0*100 Trifluoronitrate [NF3]- (g) -246.7 -248.9 ± 2.5 kJ/mol 71.002498 ± 0.000070 37366-69-1*0 Sulfate monoanion [OS(O)(O)O]- (g) -736.9 -744.6 ± 2.2 kJ/mol 96.0641 ± 0.0061 12143-45-2*0 n-Octane CH3(CH2)6CH3 (cr,l) -226.28 -249.41 ± 0.52 kJ/mol 114.2285 ± 0.0065 111-65-9*500 n-Nonane CH3(CH2)7CH3 (cr,l) -247.62 -274.48 ± 0.47 kJ/mol 128.2551 ± 0.0073 111-84-2*500 2,4,5-Trioxa-1,3-diazabicyclo[1.1.1]pentane N(O3)N (g) 602.5 593.3 ± 2.1 kJ/mol 76.01168 ± 0.00091 224950-18-9*0 1-Methyl-1-ethylium-1-yl [CH3CCH3]+ (g) 1058.3 1045.8 ± 1.9 kJ/mol 42.0792 ± 0.0024 121408-19-3*0 n-Decane CH3(CH2)8CH3 (cr,l) -272.87 -300.41 ± 0.75 kJ/mol 142.2817 ± 0.0081 124-18-5*500 1,5-Hexadiene CH2CHCH2CH2CHCH2 (cr,l) 54.56 ± 0.31 kJ/mol 82.1436 ± 0.0049 592-42-7*500 Platinum atom cation Pt+ (g) 1427.8 1428.3 ± 1.7 kJ/mol 195.0775 ± 0.0020 20561-56-2*0 Platinum dimer Pt2 (g) 823.5 822.5 ± 3.9 kJ/mol 390.1560 ± 0.0040 12596-95-1*0 Platinum hydride PtH (g) 451.6 450.7 ± 3.8 kJ/mol 196.0859 ± 0.0020 13966-55-7*0 Platinum hydride cation [PtH]+ (g) 1363.1 1382.3 ± 4.9 kJ/mol 196.0854 ± 0.0020 87882-39-1*0 Hydrogen atom H (ad, Pt(111)) -37.0 -38.7 ± 1.1 kJ/mol 1.007940 ± 0.000070 12385-13-6*1000000 Isopropylidene anion [CH3CCH3]- (g) 282.5 268.4 ± 2.0 kJ/mol 42.0803 ± 0.0024 *121408-19-3*0 Hydrogen atom H (ad, 4 Pt(111)) -33.4 -35.1 ± 1.5 kJ/mol 1.007940 ± 0.000070 12385-13-6*1000004 Nitrogen atom dianion [N]-2 (g) 1062.8 1065.0 ± 2.8 kJ/mol 14.007837 ± 0.000070 16727-21-2*0 Diazirinylium [HC(NN)]+ (g, singlet) 1384.8 1381.2 ± 2.1 kJ/mol 41.03157 ± 0.00082 77116-26-8*2 Ketene CH2CO (g, para singlet) -45.33 -48.39 ± 0.11 kJ/mol 42.0367 ± 0.0016 463-51-4*21 Iminomethylimidogen cation [NCHN]+ (g, triplet) 1677.6 1676.4 ± 2.3 kJ/mol 41.03157 ± 0.00082 *150296-30-3*1 Iminomethylimidogen anion [NCHN]- (g, triplet) 405.3 402.1 ± 2.5 kJ/mol 41.03267 ± 0.00082 150296-30-3*1 Difluoroaminylium [NF2]+ (g, triplet) 1376.5 1373.9 ± 2.4 kJ/mol 52.002998 ± 0.000070 31685-31-1*1 Iodine monochloride ICl (l) -24.048 ± 0.063 kJ/mol 162.35717 ± 0.00090 7790-99-0*590 Tetrafluorohydrazine NF2NF2 (g, gauche) -12.5 -22.1 ± 1.4 kJ/mol 104.00709 ± 0.00014 10036-47-2*2 Ammonia NH3 (aq, 10000 H2O) -80.45 ± 0.41 kJ/mol 17.03056 ± 0.00022 7664-41-7*850 Fluorine atom pentacation [F]+5 (g) 30617.6 30619.4 ± 1.8 kJ/mol 18.99566030 ± 0.00000050 14701-05-4*0 Trihydrogen H(HH) (g, 2s 2A1' Ry) 745.878 743.094 ± 0.062 kJ/mol 3.02382 ± 0.00021 12184-91-7*1 (Iminomethyl)imidogen HNCHN (g, triplet) 420.1 413.3 ± 2.9 kJ/mol 42.04006 ± 0.00082 87570-07-8*1 Chlorine atom dication [Cl]+2 (g) 3668.474 3670.081 ± 0.013 kJ/mol 35.45160 ± 0.00090 15723-23-6*0 Bicyclo[1.1.0]buta-1,3-diene-2,4-diyl C(CC)C (g, singlet) 1047.14 1054.73 ± 0.68 kJ/mol 48.0428 ± 0.0032 12184-80-4*2 Fluoroimidogen NF (g, singlet) 369.43 369.41 ± 0.80 kJ/mol 33.005143 ± 0.000070 13967-06-1*2 2-Hydroxyethylium [CH2CH2OH]+ (g, gauche) 1024.8 1012.2 ± 2.0 kJ/mol 45.0600 ± 0.0017 38607-31-7*1 Methylaminyliumyl [CH3N]+ (g, doublet ?) 1388.2 1381.9 ± 2.2 kJ/mol 29.04071 ± 0.00083 56924-51-7*1 Formaldehyde CH2O (g, para singlet) -105.380 -109.220 ± 0.094 kJ/mol 30.02598 ± 0.00087 50-00-0*21 Polyoxymethylene CH2O (cr, polyoxymethylene) -170.85 ± 0.21 kJ/mol 30.02598 ± 0.00087 9002-81-7*500 Ethynylaminylium [HCCNH]+ (g, singlet) 1350.6 1348.8 ± 2.5 kJ/mol 40.0435 ± 0.0016 103835-08-1*2 Formaldehyde CH2O (aq, unhydrol) -165.65 ± 0.22 kJ/mol 30.02598 ± 0.00087 50-00-0*1000 1,3-Butadiyn-4-ylium-1-yl [CCCC]+ (g) 2109.8 2120.5 ± 2.8 kJ/mol 48.0423 ± 0.0032 124708-46-9*0 Dioxaziridine HN(OO) (g) 277.5 270.8 ± 1.9 kJ/mol 47.01348 ± 0.00061 67394-35-8*0 1,3-Butadiyne-1,4-diyl CCCC (g, triplet) 1052.24 1062.21 ± 0.64 kJ/mol 48.0428 ± 0.0032 78015-07-3*1 Peroxyhypochlorous acid cation [HOOCl]+ (g, cis) 1050.8 1045.2 ± 2.5 kJ/mol 68.4589 ± 0.0011 *67952-07-2*2 Oxygen atom dication [O]+2 (g) 4949.458 4953.000 ± 0.013 kJ/mol 15.99830 ± 0.00030 14127-63-0*0 Dinitrogen dimer (N2)2 (g) -0.88 0.84 ± 0.67 kJ/mol 56.02696 ± 0.00028 154680-01-0*0 Propadienylidene CH2CC (g, singlet) 554.47 555.61 ± 0.39 kJ/mol 38.0480 ± 0.0024 60731-10-4*2 Tetrabromomethane CBr4 (cr, monoclinic) 60.61 ± 0.96 kJ/mol 331.6267 ± 0.0041 558-13-4*500 Bromomethane CH3Br (l) -56.17 -59.19 ± 0.20 kJ/mol 94.9385 ± 0.0013 74-83-9*590 Fluorine atom octacation [F]+8 (g) 155686.5 155688.3 ± 1.8 kJ/mol 18.99401456 ± 0.00000050 15721-58-1*0 Ammonia NH3 (aq, 100000 H2O) -80.06 ± 0.41 kJ/mol 17.03056 ± 0.00022 7664-41-7*861 Hydrogen fluoride HF (aq, undissoc) -321.36 ± 0.16 kJ/mol 20.006343 ± 0.000070 7664-39-3*1000 Peroxyhypochlorous acid anion [HOOCl]- (g, trans quartet) -2.8 -3.3 ± 2.6 kJ/mol 68.4600 ± 0.0011 *67952-08-3*1 Carbon pentacation [C]+5 (g) 52824.592 52829.739 ± 0.050 kJ/mol 12.00796 ± 0.00080 14280-11-6*0 Fluorine atom hexacation [F]+6 (g) 45781.5 45783.3 ± 1.8 kJ/mol 18.99511172 ± 0.00000050 14701-04-3*0 1,2-Propadien-1-ylium-1-yl-3-ylidene [CCC]+ (g) 1939.2 1947.1 ± 1.3 kJ/mol 36.0316 ± 0.0024 118090-85-0*0 Fluorine atom F (g, 2P3/2) 77.254 79.039 ± 0.017 kJ/mol 18.99840320 ± 0.00000050 14762-94-8*1 Propylidene CH3CH2CH (g, triplet) 349.52 335.76 ± 0.92 kJ/mol 42.0797 ± 0.0024 6700-78-3*1 Hydroxylamine NH2OH (cr,l) -107.44 ± 0.60 kJ/mol 33.02996 ± 0.00037 7803-49-8*500 Deuteride D- (g) 146.991 148.904 ± 0.0021 kJ/mol 2.01465035791 ± 0.00000000040 14452-69-8*0 Nitrosyl nitrate ONONO2 (g, cis-perp) 60.4 52.5 ± 1.9 kJ/mol 92.0111 ± 0.0012 15969-55-8*2 Methyl acetate CH3C(O)OCH3 (g) -394.13 -413.00 ± 0.56 kJ/mol 74.0785 ± 0.0025 79-20-9*0 Ethyl bromide CH3CH2Br (l) -55.37 -90.90 ± 0.25 kJ/mol 108.9651 ± 0.0019 74-96-4*500 Carbon hexacation [C]+6 (g) 100101.747 100106.893 ± 0.050 kJ/mol 12.00741 ± 0.00080 16249-02-8*0 Hydroxymethylene HCOH (g) 112.70 108.94 ± 0.27 kJ/mol 30.02598 ± 0.00087 19710-56-6*0 Hydrogen fluoride HF (aq, 3 H2O) -320.69 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*805 Chlorodioxidenium [ClOO]+ (g) 1215.1 1212.9 ± 6.3 kJ/mol 67.4510 ± 0.0011 64710-10-7*0 Chlorine trifluoride cation [FCl(F)F]+ (g) 1053.5 1049.2 ± 2.3 kJ/mol 92.44736 ± 0.00090 478167-77-0*0 Difluorovinylidene cation [CCF2]+ (g) 1181.5 1183.0 ± 2.3 kJ/mol 62.0177 ± 0.0016 268566-71-8*0 Oxygen atom octacation [O]+8 (g) 197447.75 197449.60 ± 0.12 kJ/mol 15.99501 ± 0.00030 21450-98-6*0 1,2-Diiodoacetylene ICCI (g) 416.0 416.8 ± 2.5 kJ/mol 277.8303 ± 0.0016 624-74-8*0 Dioxofluorine anion [OFO]- (g) 155.9 154.4 ± 2.5 kJ/mol 50.99775 ± 0.00060 *175861-93-5*0 2-Oxo-1-ethylium-1-yl [HCC(O)H]+ (g, syn-quartet) 1292.1 1288.7 ± 2.4 kJ/mol 42.0361 ± 0.0016 214464-96-7*12 sec-Butylium [CH3CH2CHCH3]+ (g) 792.8 769.2 ± 1.5 kJ/mol 57.1137 ± 0.0033 16548-59-7*0 Chloro(chlorooxy)methylene ClCOCl (g, trans triplet) 101.1 104.7 ± 4.8 kJ/mol 98.9155 ± 0.0020 479587-31-0*12 Oxoethylidene anion [HCC(O)H]- (g, syn-gauche) 92.3 89.0 ± 2.3 kJ/mol 42.0372 ± 0.0016 106543-38-8*2 1,3,5-Hexatriynylium [CCCCCCH]+ (g, singlet) 1952.6 1961.4 ± 7.6 kJ/mol 73.0716 ± 0.0048 81932-75-4*2 Methyl formate HC(O)OCH3 (g) -346.82 -359.87 ± 0.61 kJ/mol 60.0520 ± 0.0017 107-31-3*0 Fluorine atom tetracation [F]+4 (g) 19594.3 19596.6 ± 1.7 kJ/mol 18.99620888 ± 0.00000050 14700-79-9*0 Ethyl formate HC(O)OCH2CH3 (g) -375.0 -393.7 ± 1.0 kJ/mol 74.0785 ± 0.0025 109-94-4*0 Carbon suboxide OCCCO (cr,l) -131.18 -116.15 ± 0.97 kJ/mol 68.0309 ± 0.0025 504-64-3*500 Nitride [N]-3 (g) 1879.1 1881.0 ± 4.4 kJ/mol 14.008386 ± 0.000070 18851-77-9*0 Water H2O (cr) -286.273 -292.713 ± 0.022 kJ/mol 18.01528 ± 0.00033 7732-18-5*510 Hypoiodite [IO]- (aq) -116.3 ± 5.4 kJ/mol 142.90442 ± 0.00030 15065-65-3*800 Carbon monoxide CO (g, singlet) -113.799 -110.518 ± 0.026 kJ/mol 28.01010 ± 0.00085 630-08-0*2 m-Benzyne C6H4 (g, triplet) 615.1 605.7 ± 1.4 kJ/mol 76.0960 ± 0.0048 1828-89-3*1 Chlorine atom tetracation [Cl]+4 (g) 12615.5 12617.1 ± 4.6 kJ/mol 35.45051 ± 0.00090 22541-74-8*0 Methylene CH2 (g) 391.076 391.622 ± 0.094 kJ/mol 14.02658 ± 0.00081 2465-56-7*0 Fulvenallene CH2CC(CHCHCHCH) (g, triplet) 549.1 536.7 ± 2.4 kJ/mol 90.1225 ± 0.0056 27041-32-3*1 Cycloheptatetraene C(CHCHCHCHCHCH) (g, triplet) 529.1 515.1 ± 2.3 kJ/mol 90.1225 ± 0.0056 52783-93-4*1 4,5-Bis(methylene)-2-cyclopenten-1-yl CH(CHC(CH2)C(CH2)CH) (g) 315.3 297.1 ± 2.0 kJ/mol 91.1305 ± 0.0056 302792-28-5*0 2,5-Bis(methylene)-3-cyclopenten-1-yl CH(C(CH2)CHCHC(CH2)) (g) 321.0 302.8 ± 2.0 kJ/mol 91.1305 ± 0.0056 512782-58-0*0 Tetraoxodinitrate anion [O2NNO2]- (g) -184.6 -187.8 ± 2.4 kJ/mol 92.0116 ± 0.0012 63552-02-3*0 Dioxofluorine cation [OFO]+ (g) 1667.0 1664.8 ± 2.8 kJ/mol 50.99665 ± 0.00060 223566-05-0*0 Hypochlorite [ClO]- (aq) -110.484 ± 0.076 kJ/mol 51.45265 ± 0.00095 14380-61-1*1000 Isocyanogen bromide anion [BrNC]- (g) 105.1 101.9 ± 4.6 kJ/mol 105.9220 ± 0.0013 *238754-53-5*0 1-Methylethenyl hydroperoxide CH2C(CH3)OOH (g, gauche-perp I) -54.9 -72.9 ± 2.1 kJ/mol 74.0785 ± 0.0025 177944-34-2*21 Tropylide [CH(CHCHCHCHCHCH)]- (g) 261.7 245.4 ± 2.0 kJ/mol 91.1310 ± 0.0056 34464-18-1*0 Isoindene cation [C6H4(CHCH2CH)]+ (g) 985.2 961.9 ± 1.8 kJ/mol 116.1593 ± 0.0072 1442045-79-5*0 Indenylium [C6H4(CHCHCH)]+ (g, triplet) 1081.2 1061.7 ± 2.2 kJ/mol 115.1513 ± 0.0072 12203-21-3*1 Acetoxy CH3C(O)O (g) -182.02 -190.74 ± 0.76 kJ/mol 59.0440 ± 0.0017 13799-69-4*0 Carbon trication [C]+3 (g) 8770.930 8776.077 ± 0.047 kJ/mol 12.00905 ± 0.00080 14067-06-2*0 Water trimer (H2O)3 (g) -762.64 -776.75 ± 0.20 kJ/mol 54.04584 ± 0.00099 31014-12-7*0 Fluorine atom heptacation [F]+7 (g) 63649.3 63651.1 ± 1.8 kJ/mol 18.99456314 ± 0.00000050 14700-77-7*0 Difluorodioxidanium [FOOF]+ (g, cis) 1287.3 1283.1 ± 2.3 kJ/mol 69.99506 ± 0.00060 *7783-44-0*2 Propionic acid CH3CH2C(O)OH (g) -435.77 -453.66 ± 0.60 kJ/mol 74.0785 ± 0.0025 79-09-4*0 Hypoiodous acid HOI (aq, undissoc) -146.9 ± 4.9 kJ/mol 143.91181 ± 0.00031 14332-21-9*1000 Chlorine atom hexacation [Cl]+6 (g) 28501. 28503. ± 11. kJ/mol 35.44941 ± 0.00090 22541-73-7*0 1-Hydroxyethenylium [CH2COH]+ (g, anti-triplet) 1025.4 1018.3 ± 2.9 kJ/mol 43.0441 ± 0.0016 41084-89-3*11 2-Methyl-2-propanol (CH3)3COH (l) -358.9 ± 1.9 kJ/mol 74.1216 ± 0.0033 75-65-0*590 Oxygen atom trication [O]+3 (g) 10249.928 10252.880 ± 0.018 kJ/mol 15.99775 ± 0.00030 14127-64-1*0 2-Propen-1-ylium-1-ylidene [CH2CHC]+ (g) 1373.2 1369.7 ± 2.0 kJ/mol 39.0554 ± 0.0024 88000-25-3*0 Fluorine atom trication [F]+3 (g) 11182.872 11186.697 ± 0.032 kJ/mol 18.99675746 ± 0.00000050 14700-88-0*0 Acetaldehyde CH3CHO (cr,l) -186.89 -191.60 ± 0.28 kJ/mol 44.0526 ± 0.0017 75-07-0*500 Glycinate [NH2CH2C(O)O]- (aq) -470.09 ± 0.21 kJ/mol 74.0592 ± 0.0017 23297-34-9*800 Dihydrogen anion [H2]- (g) 253.8 254.7 ± 1.2 kJ/mol 2.01643 ± 0.00014 12184-89-3*0 Difluorine cation [F2]+ (g) 1514.301 1514.475 ± 0.013 kJ/mol 37.9962578 ± 0.0000010 12184-86-0*0 Bromodioxy BrOO (g) 116.8 107.7 ± 3.8 kJ/mol 111.9028 ± 0.0012 67177-47-3*0 Hydrogen bromide HBr (aq, 2570 H2O) -120.24 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*952 Succinic acid (CH2C(O)OH)2 (cr,l) -918.49 -940.21 ± 0.12 kJ/mol 118.0880 ± 0.0034 110-15-6*500 Ethynylene C2 (g, singlet) 819.984 826.557 ± 0.085 kJ/mol 24.0214 ± 0.0016 12070-15-4*2 Peroxyformate [HC(O)OO]- (g, anti) -320.6 -326.5 ± 1.7 kJ/mol 61.0174 ± 0.0012 104960-05-6*2 1,2-Dibromoethane CH2BrCH2Br (cr,l) -80.1 ± 1.2 kJ/mol 187.8612 ± 0.0026 106-93-4*500 Peroxyformyl HC(O)OO (g, anti) -90.4 -95.9 ± 1.7 kJ/mol 61.0168 ± 0.0012 56240-83-6*2 1,3-Butadien-2-ol CH2C(OH)CHCH2 (g, s-cis, syn) -42.6 -59.1 ± 2.3 kJ/mol 70.0898 ± 0.0032 59120-04-6*21 1,3-Butadien-2-ol CH2C(OH)CHCH2 (g, s-trans) -53.3 -68.6 ± 1.5 kJ/mol 70.0898 ± 0.0032 59120-04-6*1 Hydroxyoxoammoniumyl [HONO]+ (g, cis) 1014.8 1008.4 ± 2.0 kJ/mol 47.01293 ± 0.00061 80371-48-8*2 Hydrogen peroxide cation [HOOH]+ (g, trans, ortho) 897.30 890.32 ± 0.51 kJ/mol 34.01413 ± 0.00062 12325-10-9*11 Acrolein CH2CHCHO (g) -55.11 -65.20 ± 0.64 kJ/mol 56.0633 ± 0.0024 107-02-8*0 1-Oxo-2-propenide [CH2CHCO]- (g, II) 83.6 78.7 ± 2.5 kJ/mol 55.0559 ± 0.0024 78944-75-9*2 Propadien-1-olate [CH2CCHO]- (g) 1.5 -4.4 ± 2.5 kJ/mol 55.0559 ± 0.0024 109686-13-7*0 1-Formylethenylium [CH2CCHO]+ (g, triplet) 1158.8 1154.2 ± 3.0 kJ/mol 55.0548 ± 0.0024 101705-89-9*1 3-Oxo-1-propenyl CHCHCHO (g, trans) 190.97 184.99 ± 0.91 kJ/mol 55.0553 ± 0.0024 206255-29-0*1 3-Oxo-1-propenyl CHCHCHO (g, anti-cis) 191.7 185.7 ± 2.1 kJ/mol 55.0553 ± 0.0024 206255-29-0*21 Nitrous acid anion [HONO]- (g, trans) -105.4 -109.4 ± 1.8 kJ/mol 47.01403 ± 0.00061 256393-36-9*1 2-Formylethen-1-ide [CHCHCHO]- (g, anti-cis) 30.5 23.8 ± 3.1 kJ/mol 55.0559 ± 0.0024 135924-69-5*21 1,2-Propadien-1-one cation [CH2CCO]+ (g) 1012.8 1011.4 ± 1.8 kJ/mol 54.0468 ± 0.0024 87612-93-9*0 Hypochloroperoxoous acid, hydroxy ester HOOOCl (g, anti) 48.7 41.8 ± 2.5 kJ/mol 84.4588 ± 0.0013 928652-99-7*2 2-Propynal cation [CHCCHO]+ (g) 1168.4 1167.2 ± 1.2 kJ/mol 54.0468 ± 0.0024 100815-70-1*0 Formylethynyl cation [CC(CHO)]+ (g, singlet) 1540.0 1541.9 ± 2.7 kJ/mol 53.0389 ± 0.0024 *85905-64-2*2 Formylethynyl cation [CCCHO]+ (g, triplet) 1540.7 1542.9 ± 2.8 kJ/mol 53.0389 ± 0.0024 *85905-64-2*1 Carbide [C]-4 (g) 2709.5 2714.7 ± 2.7 kJ/mol 12.01289 ± 0.00080 12385-15-8*0 Hydrogen peroxide cation [HOOH]+ (g, cis, para) 931.06 924.21 ± 0.98 kJ/mol 34.01413 ± 0.00062 12325-10-9*22 Oxygen atom heptacation [O]+7 (g) 113369.48 113371.34 ± 0.12 kJ/mol 15.99556 ± 0.00030 14274-89-6*0 (Hydroxyimino)methyl HCNOH (g, trans-cis) 258.9 252.8 ± 2.0 kJ/mol 44.03272 ± 0.00087 206442-92-4*2 2-Iminoethyl CH2CHNH (g, syn) 221.7 210.4 ± 1.8 kJ/mol 42.0599 ± 0.0016 73843-90-0*1 2-Iminoethyl anion [CH2CHNH]- (g, anti) 110.7 100.2 ± 2.3 kJ/mol 42.0604 ± 0.0016 73843-87-5*2 Cyanoacetylene cation [HCCCN]+ (g) 1495.59 1497.89 ± 0.57 kJ/mol 51.0462 ± 0.0024 85398-68-1*0 Isocyanoacetylene cation [HCCNC]+ (g) 1567.8 1570.4 ± 1.3 kJ/mol 51.0462 ± 0.0024 145076-03-5*0 Cyanoethynylium [CCCN]+ (g) 1867.6 1874.3 ± 3.2 kJ/mol 50.0383 ± 0.0024 104233-69-4*0 Fluorosyl fluoride FFO (g, singlet) 227. 225. ± 21. kJ/mol 53.99621 ± 0.00030 86825-57-2*2 2-Iminoethylium [CH2CHNH]+ (g, singlet) 1108.4 1097.7 ± 2.9 kJ/mol 42.0594 ± 0.0016 73843-91-1*2 mu-Oxodichlorate anion [ClOCl]- (g) -147.8 -147.7 ± 2.5 kJ/mol 86.9053 ± 0.0018 365546-30-1*0 1-Hydroperoxyethylium [CH3CHOOH]+ (g, singlet) 690.7 675.8 ± 1.5 kJ/mol 61.0594 ± 0.0017 *126898-98-4*2 3-Imino-2-propen-1-ylidene CHCHCNH (g, singlet) 530.7 526.4 ± 1.2 kJ/mol 53.0627 ± 0.0024 916765-05-4*1 (E)-2-Iminoethylium [CH2CHNH]+ (g, anti) 1108.4 1094.9 ± 2.9 kJ/mol 42.0594 ± 0.0016 91127-33-2*0 2-(Methylidyneamino)ethenyl CHCHNCH (g, singlet) 600.7 596.4 ± 1.2 kJ/mol 53.0627 ± 0.0024 123416-74-0*1 (Z)-2-Iminoethylium [CH2CHNH]+ (g, syn) 1151.8 1143.1 ± 3.3 kJ/mol 42.0594 ± 0.0016 91127-34-3*0 (Z)-2-Iminoethylium [CH2CHNH]+ (g, syn-triplet) 1151.8 1143.1 ± 3.3 kJ/mol 42.0594 ± 0.0016 91127-34-3*11 Nitrogen atom tetracation [N]+4 (g) 16781.74 16783.61 ± 0.23 kJ/mol 14.004546 ± 0.000070 14452-70-1*0 Carbonic acid C(O)(OH)2 (aq, undissoc) -698.669 ± 0.028 kJ/mol 62.0248 ± 0.0012 463-79-6*1000 Tetraoxygen O4 (g, D2h singlet) 69.8 65.1 ± 4.4 kJ/mol 63.9976 ± 0.0012 12596-83-7*21 Tetraoxygen O4 (g, D2d singlet) 399.0 393.4 ± 3.9 kJ/mol 63.9976 ± 0.0012 12596-83-7*23 Tetraoxygen O4 (g, D3h singlet) 465.6 459.6 ± 4.2 kJ/mol 63.9976 ± 0.0012 12596-83-7*24 2-Hydroperoxyethyl CH2CH2OOH (g, anti-anti) 65.2 51.4 ± 2.2 kJ/mol 61.0599 ± 0.0017 126898-97-3*11 Dimethyl carbonate C(O)(OCH3)2 (g) -550.03 -570.45 ± 0.37 kJ/mol 90.0779 ± 0.0026 616-38-6*0 1,2-Butadien-1-ylium-1-yl [CH3CHCC]+ (g) 1467.0 1461.8 ± 3.1 kJ/mol 52.0740 ± 0.0032 161054-21-3*0 Bicyclo[1.1.0]butan-3-id-1-yl [CH2(CC)CH2]- (g) 524.7 516.0 ± 2.6 kJ/mol 52.0751 ± 0.0032 131273-95-5*0 1,2-Cyclobutadiene C(CHCH2CH) (g) 586.0 579.4 ± 2.2 kJ/mol 52.0746 ± 0.0032 50682-90-1*0 Trioxodinitrate anion [ONN(O)O]- (g, non-vdW) -87.3 -93.1 ± 2.2 kJ/mol 76.01223 ± 0.00091 194856-62-7*1 Nitrogen atom pentacation [N]+5 (g) 26226.70 26228.56 ± 0.23 kJ/mol 14.003997 ± 0.000070 20508-99-0*0 Hydrazine monohydrate (NH2NH2)(H2O) (l) -242.58 ± 0.19 kJ/mol 50.06052 ± 0.00053 7803-57-8*500 Formylimidogen HC(O)N (g, singlet) 245.3 242.1 ± 3.3 kJ/mol 43.02478 ± 0.00086 42288-92-6*2 But-3-en-1-yn-1-ide [CH2CHCC]- (g, triplet) 559.2 558.5 ± 2.2 kJ/mol 51.0672 ± 0.0032 58870-47-6*1 Chlorine atom pentacation [Cl]+5 (g) 19147. 19149. ± 11. kJ/mol 35.44996 ± 0.00090 20337-89-7*0 Ammonia NH3 (aq, 5000 H2O) -80.50 ± 0.41 kJ/mol 17.03056 ± 0.00022 7664-41-7*844 Trioxirane cation [O(OO)]+ (g) 1444.4 1442.2 ± 2.2 kJ/mol 47.99765 ± 0.00090 *153851-84-4*0 Nitrogen atom anion N- (g) 488.2 490.5 ± 2.3 kJ/mol 14.007289 ± 0.000070 17778-87-9*0 Trioxygen difluoride FOOOF (g) 112.5 107.3 ± 1.1 kJ/mol 85.99501 ± 0.00090 16829-28-0*0 Chlorine atom Cl (g, 2P3/2) 119.621 121.228 ± 0.0011 kJ/mol 35.45270 ± 0.00090 22537-15-1*1 Silicon atom dication [Si]+2 (g) 2814.00 2816.98 ± 0.56 kJ/mol 28.08440 ± 0.00030 14175-55-4*0 Silicon atom trication [Si]+3 (g) 6045.58 6048.56 ± 0.56 kJ/mol 28.08385 ± 0.00030 14175-56-5*0 Methyl hydrocarbonate C(O)(OH)OCH3 (g) -576.99 -591.80 ± 0.87 kJ/mol 76.0514 ± 0.0019 7456-87-3*0 Oxygen atom tetracation [O]+4 (g) 17719.207 17721.064 ± 0.025 kJ/mol 15.99721 ± 0.00030 14127-65-2*0 Formic acid HC(O)OH (aq, undissoc) -425.34 ± 0.45 kJ/mol 46.0254 ± 0.0010 64-18-6*1000 Dioxosilane SiO2 (cr, tridymite) -901.5 -906.3 ± 1.4 kJ/mol 60.08430 ± 0.00067 7631-86-9*515 2-Aminoethenylium [CHCHNH2]+ (g, syn triplet) 1117.9 1106.8 ± 2.4 kJ/mol 42.0594 ± 0.0016 64724-21-6*11 Oxosilyliumyl [SiO]+ (g) 1022.0 1023.1 ± 2.9 kJ/mol 44.08435 ± 0.00042 12359-18-1*0 1-Methylethenylium [CH3CCH2]+ (g) 995.2 986.0 ± 1.9 kJ/mol 41.0713 ± 0.0024 50457-57-3*0 Acetylene anion [HCCH]- (g) 356.9 356.7 ± 1.9 kJ/mol 26.0378 ± 0.0016 50443-89-5*0 2-Aminoethenyl anion [CHCHNH2]- (g, syn) 242.0 231.3 ± 2.6 kJ/mol 42.0604 ± 0.0016 *64724-21-6*1 Cyclopentadiene CH2(CHCHCHCH) (l) 110.39 ± 0.56 kJ/mol 66.1011 ± 0.0040 542-92-7*590 1-Methylethenyl anion [CH3CCH2]- (g) 199.4 188.2 ± 2.0 kJ/mol 41.0723 ± 0.0024 65887-19-6*0 Nitrogen atom hexacation [N]+6 (g) 79493.10 79494.96 ± 0.23 kJ/mol 14.003449 ± 0.000070 15721-56-9*0 mu-Hydrotetrahydrodisilicon cation [SiH2(HSiH2)]+ (g) 981.6 968.8 ± 2.8 kJ/mol 61.21015 ± 0.00069 160896-65-1*0 Di-mu-hydrotrihydrodisilicon cation [SiH2(HSiHH)]+ (g) 1033.7 1020.3 ± 2.8 kJ/mol 61.21015 ± 0.00069 *160896-65-1*0 Chlorine atom trication [Cl]+3 (g) 7487.2 7490.2 ± 3.3 kJ/mol 35.45105 ± 0.00090 16547-50-5*0 Disilene anion [SiH2SiH2]- (g) 178.6 170.2 ± 3.0 kJ/mol 60.20331 ± 0.00066 157379-08-3*0 Silylsilylene anion [SiH3SiH]- (g) 160.3 151.6 ± 3.0 kJ/mol 60.20331 ± 0.00066 286949-98-2*0 Silylsilylene SiH3SiH (g, triplet) 381.3 372.5 ± 2.6 kJ/mol 60.20276 ± 0.00066 50420-90-1*1 mu-Hydrotrihydrodisilicon SiH2(HSiH) (g) 317.9 307.8 ± 2.1 kJ/mol 60.20276 ± 0.00066 497967-56-3*0 Hydrogen iodide HI (aq, 5130 H2O) -56.642 ± 0.089 kJ/mol 127.912410 ± 0.000076 10034-85-2*958 mu-Hydrotrihydrodisilicon cation [Si(HSiH3)]+ (g) 1160.1 1152.0 ± 2.6 kJ/mol 60.20221 ± 0.00066 *497967-55-2*0 Hydrogen fluoride HF (aq, 100 H2O) -322.01 ± 0.10 kJ/mol 20.006343 ± 0.000070 7664-39-3*828 Tribromine cation [Br3]+ (g) 1036.3 1013.6 ± 2.5 kJ/mol 239.7115 ± 0.0030 33105-86-1*0 Silyloxoniumylidene [SiH3O]+ (g, triplet) 1096.3 1089.9 ± 2.9 kJ/mol 47.10817 ± 0.00047 152720-17-7*1 Tribromide [Br3]- (aq) -129.17 ± 0.22 kJ/mol 239.7125 ± 0.0030 14522-80-6*800 Hydroxysilylium [SiH2OH]+ (g) 600.3 591.6 ± 2.9 kJ/mol 47.10817 ± 0.00047 66639-72-3*0 Ammonium oxide (NH4)2O (cr,l) -428.46 -430.46 ± 0.61 kJ/mol 52.07640 ± 0.00065 12161-77-2*500 1-Propen-1-yl-3-ylidene CHCHCH (g, quartet) 656.8 653.4 ± 1.1 kJ/mol 39.0559 ± 0.0024 84654-90-0*1 Nitrosyl nitrite anion [ONONO]- (g, t, c) -100.3 -103.4 ± 2.9 kJ/mol 76.01223 ± 0.00091 *122413-35-8*2 1,5-Hexadiyne HCCCH2CH2CCH (cr,l) 386.0 ± 1.9 kJ/mol 78.1118 ± 0.0048 628-16-0*500 Ammonia NH3 (aq) -77.033 ± 0.056 kJ/mol 17.03056 ± 0.00022 7664-41-7*800 Ammonia NH3 (aq, 1 H2O) -75.73 ± 0.57 kJ/mol 17.03056 ± 0.00022 7664-41-7*801 Bicyclo[3.1.0]hexa-1,3-diene CH2((CCH)(CHCHCH)) (g) 406.5 390.9 ± 2.2 kJ/mol 78.1118 ± 0.0048 28425-23-2*0 3-Ethenylidenecyclobutene CH2CC(CHCHCH2) (g) 406.6 392.5 ± 2.3 kJ/mol 78.1118 ± 0.0048 813466-23-8*0 3,4-Hexadien-1-yne HCCCHCCHCH3 (g) 418.7 407.5 ± 2.6 kJ/mol 78.1118 ± 0.0048 194024-51-6*0 3-Ethynylcyclobutene HCCCH(CHCHCH2) (g) 421.8 407.4 ± 2.4 kJ/mol 78.1118 ± 0.0048 175090-90-1*0 Ammonia NH3 (aq, 2 H2O) -78.02 ± 0.41 kJ/mol 17.03056 ± 0.00022 7664-41-7*803 Ammonia NH3 (aq, 3 H2O) -78.87 ± 0.41 kJ/mol 17.03056 ± 0.00022 7664-41-7*805 1,2,4-Trioxolane O(CH2OOCH2) (g) -204.6 -222.8 ± 2.1 kJ/mol 76.0514 ± 0.0019 289-14-5*0 Hydrogen peroxide HOOH (g, para) -129.418 -135.404 ± 0.058 kJ/mol 34.01468 ± 0.00062 7722-84-1*2 Hydrazoic acid anion [HNNN]- (g, cis) 316.3 310.1 ± 2.3 kJ/mol 43.02871 ± 0.00022 203264-98-6*2 Isocyanogen cation [CNCN]+ (g) 1654.2 1656.5 ± 1.4 kJ/mol 52.0343 ± 0.0016 133415-63-1*0 2-Ethynyl-2-cyclopropen-1-ylidene HCCC(CCH) (g) 726.2 727.4 ± 3.2 kJ/mol 62.0694 ± 0.0040 117992-84-4*0 Oxygen atom pentacation [O]+5 (g) 28708.788 28710.645 ± 0.053 kJ/mol 15.99666 ± 0.00030 14127-66-3*0 Pyramidane C(CH(CHCH)CH) (g) 602.4 593.9 ± 2.3 kJ/mol 64.0853 ± 0.0040 66202-79-7*0 Spiropentadiene C((CHCH))2 (g) 651.9 644.6 ± 2.3 kJ/mol 64.0853 ± 0.0040 1727-65-7*0 Oxoniumyl ion [H2O]+ (g, ortho) 978.496 975.592 ± 0.024 kJ/mol 18.01473 ± 0.00033 56583-62-1*1 Diisocyanogen cation [CNNC]+ (g, cis) 1838.6 1842.6 ± 3.1 kJ/mol 52.0343 ± 0.0016 *78800-21-2*2 2-Aminoethylium [CH2CH2NH2]+ (g, triplet) 1042.7 1026.1 ± 2.4 kJ/mol 44.0752 ± 0.0017 54088-54-9*1 2-Aminoethyl anion [CH2CH2NH2]- (g) 149.0 131.9 ± 2.1 kJ/mol 44.0763 ± 0.0017 71857-14-2*0 Ammonia NH3 (aq, 4 H2O) -79.33 ± 0.41 kJ/mol 17.03056 ± 0.00022 7664-41-7*807 Ammonia NH3 (aq, 5 H2O) -79.63 ± 0.41 kJ/mol 17.03056 ± 0.00022 7664-41-7*809 Hydrazoic acid HNNN (aq, undissoc) 257.71 ± 0.48 kJ/mol 43.02816 ± 0.00022 7782-79-8*1000 1,2-Diphenylethane C6H5CH2CH2C6H5 (g) 180.72 142.23 ± 0.76 kJ/mol 182.2610 ± 0.0112 103-29-7*0 Hydrazoic acid HNNN (aq) 272.69 ± 0.47 kJ/mol 43.02816 ± 0.00022 7782-79-8*800 2-Naphthalenylium [C6H4(CHCCHCH)]+ (g) 1195.7 1177.8 ± 3.5 kJ/mol 127.1620 ± 0.0080 79319-69-0*0 1-Naphthalenylium [C6H4(CCHCHCH)]+ (g) 1192.8 1174.8 ± 3.4 kJ/mol 127.1620 ± 0.0080 79319-68-9*0 Ammonia NH3 (aq, 10 H2O) -80.16 ± 0.41 kJ/mol 17.03056 ± 0.00022 7664-41-7*815 Ammonia NH3 (aq, 20 H2O) -80.38 ± 0.41 kJ/mol 17.03056 ± 0.00022 7664-41-7*818 Ammonia NH3 (aq, 50 H2O) -80.52 ± 0.41 kJ/mol 17.03056 ± 0.00022 7664-41-7*822 Biphenyl C6H5C6H5 (l) 113.7 ± 1.1 kJ/mol 154.2078 ± 0.0096 92-52-4*590 2-Methylpentane CH3CH2CH2CH(CH3)2 (cr,l) -180.15 -203.81 ± 0.73 kJ/mol 86.1754 ± 0.0049 107-83-5*500 Benzophenone C6H5C(O)C6H5 (cr) -16.7 -41.9 ± 1.5 kJ/mol 182.2179 ± 0.0104 119-61-9*510 Buckminsterfullerene C60 (g) 2523.5 2518.9 ± 6.4 kJ/mol 720.6420 ± 0.0480 99685-96-8*0 Buckminsterfullerene C60 (cr,l) 2328.4 2337.9 ± 6.4 kJ/mol 720.6420 ± 0.0480 99685-96-8*500 Cyclobutatrienyl CH(CCC) (g) 962.0 965.5 ± 2.4 kJ/mol 49.0507 ± 0.0032 *99417-52-4*0 3-Methylpentane CH3CH2CH(CH3)CH2CH3 (cr,l) -177.60 -201.87 ± 0.76 kJ/mol 86.1754 ± 0.0049 96-14-0*500 Helium anion He- (g, 1s.2s.2p 4P) 1904.822 1904.822 ± 0.000 kJ/mol 4.0031506 ± 0.0000020 14452-58-5*3 Helium anion He- (g, 2p3 4S3/2) 5724.96 5724.96 ± 0.32 kJ/mol 4.0031506 ± 0.0000020 14452-58-5*4 Dihelium cation [He2]+ (g) 2143.643 2139.915 ± 0.018 kJ/mol 8.0046554 ± 0.0000040 12184-99-5*0 Dihelium anion [He2]- (g, quartet 4Pig) 1714.9 1711.2 ± 1.9 kJ/mol 8.0057526 ± 0.0000040 90188-47-9*1 Deuterium molecule cation [D2]+ (g) 1492.286 1492.361 ± 0.000 kJ/mol 4.02765497609 ± 0.00000000080 12184-84-8*0 Helium dihydride HeHH (g) -0.05 0.87 ± 0.42 kJ/mol 6.01848 ± 0.00014 33309-42-1*0 Nitrogen atom trication [N]+3 (g) 9306.69 9308.55 ± 0.23 kJ/mol 14.005094 ± 0.000070 18396-22-0*0 Helium dihydride HHeH (g) 614.5 608.9 ± 2.6 kJ/mol 6.01848 ± 0.00014 *33309-42-1*0 Dihydrohelium cation [HHeH]+ (g) 1572.2 1568.9 ± 2.4 kJ/mol 6.01793 ± 0.00014 *12500-88-8*0 Neon dication [Ne]+2 (g) 6032.988 6033.214 ± 0.0041 kJ/mol 20.17860 ± 0.00060 14041-55-5*0 Neon trication [Ne]+3 (g) 12152.403 12152.403 ± 0.032 kJ/mol 20.17805 ± 0.00060 14158-25-9*0 Neon tetracation [Ne]+4 (g) 21529.82 21531.45 ± 0.25 kJ/mol 20.17751 ± 0.00060 14041-56-6*0 Neon pentacation [Ne]+5 (g) 33711.1 33711.1 ± 1.2 kJ/mol 20.17696 ± 0.00060 14175-48-5*0 Neon hexacation [Ne]+6 (g) 48949.3 48949.3 ± 1.3 kJ/mol 20.17641 ± 0.00060 14041-57-7*0 Neon heptacation [Ne]+7 (g) 68948.7 68948.7 ± 1.4 kJ/mol 20.17586 ± 0.00060 14175-50-9*0 Neon octacation [Ne]+8 (g) 92018.2 92018.2 ± 1.4 kJ/mol 20.17531 ± 0.00060 14782-26-4*0 Neon nonacation [Ne]+9 (g) 207396.1 207396.1 ± 1.4 kJ/mol 20.17476 ± 0.00060 15721-59-2*0 2,3-Dimethylbutane CH3CH(CH3)CH(CH3)CH3 (cr,l) -182.40 -206.91 ± 0.81 kJ/mol 86.1754 ± 0.0049 79-29-8*500 2,2-Dimethylbutane CH3CH2C(CH3)3 (cr,l) -187.90 -213.62 ± 0.75 kJ/mol 86.1754 ± 0.0049 75-83-2*500 Sulfur atom dication [S]+2 (g) 3528.19 3531.88 ± 0.14 kJ/mol 32.0649 ± 0.0060 14127-58-3*0 Sulfur atom trication [S]+3 (g) 6890.8 6892.8 ± 3.2 kJ/mol 32.0644 ± 0.0060 22541-72-6*0 Sulfur atom tetracation [S]+4 (g) 11447.1 11448.8 ± 3.4 kJ/mol 32.0638 ± 0.0060 20681-10-1*0 Sulfur atom pentacation [S]+5 (g) 18451.4 18453.2 ± 3.4 kJ/mol 32.0633 ± 0.0060 14127-59-4*0 Fluorine atom dication [F]+2 (g) 5132.472 5134.257 ± 0.021 kJ/mol 18.99730604 ± 0.00000050 14701-07-6*0 Dioxathiirane S(OO) (g) 166.2 163.7 ± 2.2 kJ/mol 64.0648 ± 0.0060 191663-73-7*0 Ammonia NH3 (aq, 1000 H2O) -80.57 ± 0.41 kJ/mol 17.03056 ± 0.00022 7664-41-7*839 1-Propenylium [CH3CHCH]+ (g, trans) 1233.8 1223.4 ± 2.0 kJ/mol 41.0713 ± 0.0024 50457-58-4*1 Ammonia NH3 (aq, 100 H2O) -80.56 ± 0.41 kJ/mol 17.03056 ± 0.00022 7664-41-7*828 Sulfur trioxide OS(O)O (cr,l) -454.31 ± 0.37 kJ/mol 80.0642 ± 0.0061 7446-11-9*500 3-Oxidedioxathiirane OS(OO) (g) -127.9 -132.8 ± 2.2 kJ/mol 80.0642 ± 0.0061 2243010-16-2*0 Trioxathietane S(OOO) (g) 263.6 258.5 ± 2.3 kJ/mol 80.0642 ± 0.0061 *2243010-16-2*0 Oxadithiirane O(SS) (g) 136.4 134.3 ± 2.5 kJ/mol 80.1314 ± 0.0120 488092-02-0*0 Sulfanylideneoxidaniumthiolate SOS (g) 220.7 219.0 ± 2.0 kJ/mol 80.1314 ± 0.0120 401811-43-6*0 Thiozone cation [SSS]+ (g) 1073.1 1071.5 ± 2.0 kJ/mol 96.1975 ± 0.0180 60063-56-1*0 cyc-Thiozone cation [S(SS)]+ (g) 1040.2 1039.6 ± 2.7 kJ/mol 96.1975 ± 0.0180 *60063-56-1*0 cyc-Trisulfide [S(SS)]- (g) 15.2 14.6 ± 2.5 kJ/mol 96.1985 ± 0.0180 *12597-04-5*0 mu-Oxodichlorine cation [ClOCl]+ (g) 1130.45 1126.84 ± 0.63 kJ/mol 86.9043 ± 0.0018 51174-96-0*0 Trihydrogen (H)(HH) (g, vdW) 215.9 218.3 ± 1.1 kJ/mol 3.02382 ± 0.00021 12184-91-7*100 Cyanoamidogen HNCN (g, c-quartet) 657.4 654.6 ± 2.0 kJ/mol 41.03212 ± 0.00082 12347-01-2*22 Sulfuric acid OS(O)(OH)2 (aq) -878.92 -909.16 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*800 Ethylideneoxoniumyloxy [CH3CHOO]+ (g, syn) 957.2 944.8 ± 2.2 kJ/mol 60.0514 ± 0.0017 1427752-17-7*2 Sulfuric acid OS(O)(OH)2 (aq, 40 H2O) -886.35 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*821 Nitrogen atom dication [N]+2 (g) 4728.997 4731.825 ± 0.024 kJ/mol 14.005643 ± 0.000070 17439-59-7*0 Sulfuric acid OS(O)(OH)2 (aq, 700 H2O) -891.24 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*835 Sulfuric acid OS(O)(OH)2 (aq, 800 H2O) -891.61 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*837 Sulfuric acid OS(O)(OH)2 (aq, 1500 H2O) -893.41 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*840 Sulfuric acid OS(O)(OH)2 (aq, 2000 H2O) -894.36 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*841 Sulfuric acid OS(O)(OH)2 (aq, 3000 H2O) -895.83 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*842 Sulfuric acid OS(O)(OH)2 (aq, 5000 H2O) -897.86 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*844 2-Chloro ozone ClO(O)O (g) 265.7 265.1 ± 3.7 kJ/mol 83.4509 ± 0.0013 *141801-66-3*0 Sulfuric acid OS(O)(OH)2 (aq, 60 H2O) -886.90 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*823 Sulfuric acid OS(O)(OH)2 (aq, 80 H2O) -887.25 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*826 Sulfuric acid OS(O)(OH)2 (aq, 90 H2O) -887.40 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*827 Sulfuric acid OS(O)(OH)2 (aq, 750 H2O) -891.43 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*836 Sulfuric acid OS(O)(OH)2 (aq, 1250 H2O) -892.87 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*954 Sulfuric acid OS(O)(OH)2 (aq, 6000 H2O) -898.58 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*845 Sulfuric acid OS(O)(OH)2 (aq, 7500 H2O) -899.50 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*847 Sulfuric acid OS(O)(OH)2 (aq, 8000 H2O) -899.76 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*848 Sulfuric acid OS(O)(OH)2 (aq, 9000 H2O) -900.22 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*849 Sulfuric acid monohydrate (OS(O)(OH)2)(H2O) (cr,l) -1126.32 -1127.48 ± 0.13 kJ/mol 116.0948 ± 0.0062 10193-30-3*500 Sulfuric acid dihydrate (OS(O)(OH)2)(H2O)2 (cr,l) -1422.14 -1426.93 ± 0.14 kJ/mol 134.1100 ± 0.0063 13451-10-0*500 Sulfuric acid trihydrate (OS(O)(OH)2)(H2O)3 (cr,l) -1716.08 -1720.20 ± 0.15 kJ/mol 152.1253 ± 0.0064 40835-65-2*500 Sulfuric acid tetrahydrate (OS(O)(OH)2)(H2O)4 (cr,l) -2006.93 -2010.97 ± 0.17 kJ/mol 170.1406 ± 0.0065 37006-20-5*500 Sulfuric acid pentahydrate (OS(O)(OH)2)(H2O)5 (cr,l) -2300.36 ± 0.18 kJ/mol 188.1559 ± 0.0066 137168-49-1*500 Sulfuric acid hexahydrate (OS(O)(OH)2)(H2O)6 (cr,l) -2588.91 ± 0.20 kJ/mol 206.1712 ± 0.0068 137168-50-4*500 Sulfuric acid heptahydrate (OS(O)(OH)2)(H2O)7 (cr,l) -2876.86 ± 0.22 kJ/mol 224.1864 ± 0.0069 137168-51-5*500 Sulfuric acid octahydrate (OS(O)(OH)2)(H2O)8 (cr,l) -3164.36 ± 0.24 kJ/mol 242.2017 ± 0.0071 88434-16-6*500 Sulfuric acid nonahydrate (OS(O)(OH)2)(H2O)9 (cr,l) -3451.52 ± 0.25 kJ/mol 260.2170 ± 0.0073 137168-52-6*500 Sulfuric acid decahydrate (OS(O)(OH)2)(H2O)10 (cr,l) -3738.42 ± 0.27 kJ/mol 278.2323 ± 0.0075 137168-53-7*500 Sulfuric acid dodecahydrate (OS(O)(OH)2)(H2O)12 (cr,l) -4311.63 ± 0.31 kJ/mol 314.2628 ± 0.0079 30383-99-4*500 Sulfuric acid pentadecahydrate (OS(O)(OH)2)(H2O)15 (cr,l) -5170.52 ± 0.37 kJ/mol 368.3087 ± 0.0086 425605-43-2*500 Cyclopropane cation [CH2(CH2CH2)]+ (g) 1021.8 1006.3 ± 1.5 kJ/mol 42.0792 ± 0.0024 34496-93-0*0 1-Propenylide [CH3CHCH]- (g, trans) 210.5 199.3 ± 2.0 kJ/mol 41.0723 ± 0.0024 65887-20-9*1 Water H2O (g, para) -238.903 -241.806 ± 0.022 kJ/mol 18.01528 ± 0.00033 7732-18-5*2 Sulfur tetraoxide OS(O)(O)O (g, triplet Td) -205.2 -211.3 ± 2.6 kJ/mol 96.0636 ± 0.0061 12772-98-4*12 Hydroxylamine NH2OH (g) -33.06 -43.43 ± 0.42 kJ/mol 33.02996 ± 0.00037 7803-49-8*0 Dioxoperoxysulfane (O2S)(OO) (g, singlet Cs ?) -177.1 -177.5 ± 3.5 kJ/mol 96.0636 ± 0.0061 *103613-08-7*12 Oxonium [H3O]+ (g, para) 605.89 599.14 ± 0.17 kJ/mol 19.02267 ± 0.00037 13968-08-6*2 Vinyl hydroperoxide CH2CHOOH (g, gauche I) -21.6 -33.5 ± 1.6 kJ/mol 60.0520 ± 0.0017 66998-78-5*2 Thioformaldehyde cation [CH2S]+ (g) 1025.9 1022.4 ± 2.0 kJ/mol 46.0920 ± 0.0061 61356-81-8*0 Diazomethylium [HCNN]+ (g, singlet) 1458.9 1456.9 ± 2.2 kJ/mol 41.03157 ± 0.00082 271249-81-1*2 Dimethylsulfoxide CH3S(O)CH3 (l) -203.58 ± 0.49 kJ/mol 78.1344 ± 0.0062 67-68-5*590 Vinyl hydroperoxide CH2CHOOH (g, gauche II) -21.4 -33.1 ± 1.6 kJ/mol 60.0520 ± 0.0017 66998-78-5*3 Trihydrogen cation [H3]+ (g, para) 1110.304 1106.697 ± 0.013 kJ/mol 3.02327 ± 0.00021 28132-48-1*2 Ammonia NH3 (aq, 50000 H2O) -80.22 ± 0.41 kJ/mol 17.03056 ± 0.00022 7664-41-7*855 Ammonia NH3 (aq, 500 H2O) -80.58 ± 0.41 kJ/mol 17.03056 ± 0.00022 7664-41-7*833 Ammonium hydroxide NH4OH (aq, undissoc) -366.685 ± 0.059 kJ/mol 35.04584 ± 0.00047 1336-21-6*1000 Cycloheptatetraene C(CHCHCHCHCHCH) (g) 418.8 403.1 ± 1.3 kJ/mol 90.1225 ± 0.0056 52783-93-4*0 Hydroperoxonium [H2OOH]+ (g) 738.2 727.9 ± 1.2 kJ/mol 35.02207 ± 0.00064 70850-26-9*0 Acetic acid CH3C(O)OH (aq, 400 H2O) -484.76 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*832 Hydrogen bromide HBr (aq, 1000 H2O) -120.10 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*839 Trichlorine cation [Cl3]+ (g, triplet) 1196.6 1197.2 ± 3.2 kJ/mol 106.3576 ± 0.0027 33088-85-6*1 2-Hydroxyethyl CH2CH2OH (g) -12.87 -26.13 ± 0.48 kJ/mol 45.0605 ± 0.0017 4422-54-2*0 Tetrafluorohydrazine cation [NF2NF2]+ (g, cis ?) 1146.9 1141.5 ± 3.7 kJ/mol 104.00654 ± 0.00014 37366-75-9*2 Acetic acid CH3C(O)OH (aq, 500 H2O) -484.78 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*833 C=O-C cation [COC]+ (g) 1585.8 1592.9 ± 2.7 kJ/mol 40.0203 ± 0.0016 83483-98-1*0 Chlorine chlorite ClOClO (g) 168.6 166.4 ± 1.3 kJ/mol 102.9042 ± 0.0019 105206-44-8*0 2-Propene-1,2-diol CH2C(OH)CH2OH (g) -295.3 -314.4 ± 1.2 kJ/mol 74.0785 ± 0.0025 44169-27-9*0 Isocyanogen bromide cation [BrNC]+ (g) 1470.0 1464.3 ± 5.9 kJ/mol 105.9209 ± 0.0013 238754-53-5*0 Cyclopentadienide [CH(CHCHCHCH)]- (g) 101.19 88.21 ± 0.96 kJ/mol 65.0937 ± 0.0040 12127-83-2*0 Nitric acid HON(O)O (aq, 20 H2O) -205.90 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*818 Dichloromethylene CCl2 (g) 229.88 231.06 ± 0.64 kJ/mol 82.9161 ± 0.0020 1605-72-7*0 Hydrogen iodide HI (aq, 100 H2O) -56.042 ± 0.097 kJ/mol 127.912410 ± 0.000076 10034-85-2*828 1-Methylethenyl hydroperoxide CH2C(CH3)OOH (g) -63.4 -81.2 ± 1.3 kJ/mol 74.0785 ± 0.0025 177944-34-2*0 trans-Cycloheptene CH2(CHCHCH2CH2CH2CH2) (g) 142.0 103.9 ± 1.9 kJ/mol 96.1702 ± 0.0057 45509-99-7*0 Propylidene CH3CH2CH (g, triplet anti) 349.7 336.0 ± 2.0 kJ/mol 42.0797 ± 0.0024 6700-78-3*12 Ethoxyethene CH2CHOCH2CH3 (g, trans-perp) -108.7 -131.9 ± 2.3 kJ/mol 72.1057 ± 0.0033 109-92-2*11 Acetic acid CH3C(O)OH (aq, 555.1 H2O) -484.78 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*895 Acetic acid CH3C(O)OH (aq, 600 H2O) -484.78 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*834 Chlorous acid cation [HOClO]+ (g) 996.6 991.6 ± 3.1 kJ/mol 68.4589 ± 0.0011 *99559-66-7*0 1,3-Propanediyl CH2CH2CH2 (g) 319.3 307.9 ± 1.3 kJ/mol 42.0797 ± 0.0024 32458-33-6*0 Hydrogen chloride HCl (aq, 2400 H2O) -166.709 ± 0.024 kJ/mol 36.46064 ± 0.00090 7647-01-0*896 1-Methylethenyl hydroperoxide CH2C(CH3)OOH (g, gauche-perp II) -54.0 -72.1 ± 2.7 kJ/mol 74.0785 ± 0.0025 177944-34-2*22 Hydrogen chloride HCl (aq, 3000 H2O) -166.739 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*842 Hydrogen fluoride HF (aq, 3000 H2O) -323.83 ± 0.12 kJ/mol 20.006343 ± 0.000070 7664-39-3*842 Water H2O (g, ortho) -238.618 -241.806 ± 0.022 kJ/mol 18.01528 ± 0.00033 7732-18-5*1 Oxoniumyl ion [H2O]+ (g, para) 978.745 975.594 ± 0.024 kJ/mol 18.01473 ± 0.00033 56583-62-1*2 Carbonylmethyloxonium [CH3OCO]+ (g) 561.2 552.9 ± 3.0 kJ/mol 59.0435 ± 0.0017 24434-00-2*0 Nitrosyl nitrate ONONO2 (g) 48.3 40.4 ± 1.8 kJ/mol 92.0111 ± 0.0012 15969-55-8*0 Isoformyl anion [COH]- (g) 55.7 58.4 ± 1.8 kJ/mol 29.01859 ± 0.00086 81747-63-9*0 Indane cation [C6H4(CH2CH2CH2)]+ (g) 909.4 879.5 ± 1.7 kJ/mol 118.1752 ± 0.0072 78854-02-1*0 Dihydroxymethyl CH(OH)2 (g) -196.9 -205.2 ± 1.1 kJ/mol 47.0333 ± 0.0010 14840-85-8*0 Dihydroxymethyl CH(OH)2 (g, syn-syn) -190.6 -199.3 ± 2.2 kJ/mol 47.0333 ± 0.0010 14840-85-8*2 Dihydroxymethyl CH(OH)2 (g, anti-anti) -187.9 -196.7 ± 2.0 kJ/mol 47.0333 ± 0.0010 14840-85-8*3 Indene anion [C6H4(CHCHCH2)]- (g) 242.7 220.3 ± 3.4 kJ/mol 116.1604 ± 0.0072 39526-38-0*0 Hydrogen chloride HCl (aq, 200 H2O) -166.103 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*830 Hydrogen iodide HI (aq, 12 H2O) -54.02 ± 0.17 kJ/mol 127.912410 ± 0.000076 10034-85-2*816 Ammonium hydroxide NH4OH (aq, 4.5 H2O) -365.54 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*808 Isoindene anion [C6H4(CHCH2CH)]- (g) 239.8 217.2 ± 3.9 kJ/mol 116.1604 ± 0.0072 496764-61-5*0 Hydrogen chloride HCl (aq, 25 H2O) -164.170 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*819 Methoxyoxomethyl CH3OCO (g) -152.8 -160.5 ± 1.1 kJ/mol 59.0440 ± 0.0017 16481-04-2*0 Oxirane O(CH2CH2) (cr,l) -77.12 -77.78 ± 0.60 kJ/mol 44.0526 ± 0.0017 75-21-8*500 Indenide [C6H4(CHCHCH)]- (g) 125.3 105.3 ± 1.6 kJ/mol 115.1524 ± 0.0072 12128-54-0*0 Indenylium [C6H4(CHCHCH)]+ (g) 1030.2 1010.7 ± 2.0 kJ/mol 115.1513 ± 0.0072 12203-21-3*0 Phenol cation [C6H5OH]+ (g) 746.51 727.71 ± 0.63 kJ/mol 94.1107 ± 0.0048 40932-22-7*0 Phenol anion [C6H5OH]- (g) 23.1 8.2 ± 4.9 kJ/mol 94.1118 ± 0.0048 38752-11-3*0 Methoxyoxomethyl CH3OCO (g, anti-eclipsed) -151.9 -160.0 ± 2.1 kJ/mol 59.0440 ± 0.0017 16481-04-2*3 Hydrogen chloride HCl (aq, 3500 H2O) -166.753 ± 0.024 kJ/mol 36.46064 ± 0.00090 7647-01-0*899 Dihydroxymethylium [CH(OH)2]+ (g) 421.5 410.4 ± 3.0 kJ/mol 47.0328 ± 0.0010 180071-68-5*0 Ammonium hydroxide NH4OH (aq, 200 H2O) -366.37 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*830 Chlorine trifluoride anion [FCl(F)F]- (g) -480.4 -481.9 ± 3.5 kJ/mol 92.44846 ± 0.00090 184289-50-7*0 Hydrogen chloride HCl (aq, 4000 H2O) -166.764 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*843 Benzaldehyde cation [C6H5C(O)H]+ (g) 897.0 880.3 ± 1.7 kJ/mol 106.1214 ± 0.0056 80226-59-1*0 Benzaldehyde anion [C6H5C(O)H]- (g) -55.0 -72.7 ± 2.7 kJ/mol 106.1225 ± 0.0056 34473-57-9*0 Acetyloxoniumylidene [CH3C(O)O]+ (g, triplet) 892.4 884.0 ± 2.9 kJ/mol 59.0435 ± 0.0017 67057-47-0*1 Hydrogen fluoride HF (aq, 55.51 H2O) -321.96 ± 0.10 kJ/mol 20.006343 ± 0.000070 7664-39-3*891 Ammonium hydroxide NH4OH (aq, 300 H2O) -366.38 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*831 Benzoyl anion [C6H5CO]- (g) 70.3 57.6 ± 4.0 kJ/mol 105.1145 ± 0.0056 78944-74-8*0 Ammonium hydroxide NH4OH (aq, 400 H2O) -366.39 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*832 Hydrogen bromide HBr (aq, 5 H2O) -110.68 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*809 1-Hydroxyethylidene CH3COH (g, singlet) 57.45 47.14 ± 0.77 kJ/mol 44.0526 ± 0.0017 30967-49-8*2 Ethane anion [CH3CH3]- (g) 41.8 26.5 ± 4.4 kJ/mol 30.0696 ± 0.0017 54064-82-3*0 Hydrogen chloride HCl (aq, 5000 H2O) -166.794 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*844 Acetic acid CH3C(O)OH (aq, 700 H2O) -484.79 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*835 1-Hydroxyethylidene CH3COH (g) 57.45 47.14 ± 0.77 kJ/mol 44.0526 ± 0.0017 30967-49-8*0 Dihydroxymethylium [CH(OH)2]+ (g, anti-anti) 428.5 417.3 ± 3.4 kJ/mol 47.0328 ± 0.0010 180071-68-5*3 Trioxidane HOOOH (g) -81.75 -90.35 ± 0.40 kJ/mol 50.01408 ± 0.00091 14699-99-1*0 Propylidene CH3CH2CH (g, singlet TS) 355.7 340.8 ± 2.0 kJ/mol 42.0797 ± 0.0024 6700-78-3*2 Chlorous acid anion [HOClO]- (g) -154.3 -156.1 ± 3.3 kJ/mol 68.4600 ± 0.0011 99559-66-7*0 m-Tolualdehyde CH3C6H4C(O)H (cr, l, meta) -125.0 ± 1.2 kJ/mol 120.1485 ± 0.0064 620-23-5*500 Hydrogen iodide HI (aq, 600 H2O) -56.389 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*834 Acetate [CH3C(O)O]- (aq) -485.09 ± 0.27 kJ/mol 59.0446 ± 0.0017 71-50-1*800 2-Methanidylidynehydrazin-2-ium-1-ide [HNNC]- (g, triplet) 518.6 516.3 ± 1.6 kJ/mol 41.03267 ± 0.00082 *947408-74-4*1 Hydrogen bromide HBr (aq, 1500 H2O) -120.17 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*840 Cyanogen iodide cation [ICN]+ (g) 1271.3 1271.2 ± 1.7 kJ/mol 152.92136 ± 0.00080 34749-78-5*0 Ammonium hydroxide NH4OH (aq, 5 H2O) -365.63 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*809 Nitric acid HON(O)O (aq, 25 H2O) -205.98 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*819 (Formyloxy)methyl HC(O)OCH2 (g) -151.3 -159.3 ± 1.1 kJ/mol 59.0440 ± 0.0017 3122-12-1*0 Carboxymethyl CH2C(O)OH (g) -226.5 -236.3 ± 1.1 kJ/mol 59.0440 ± 0.0017 2887-46-9*0 Dihydroxymethylium [CH(OH)2]+ (g, syn-syn) 439.4 428.2 ± 3.4 kJ/mol 47.0328 ± 0.0010 180071-68-5*2 Dihydroxymethanide [CH(OH)2]- (g) -194.2 -202.4 ± 1.8 kJ/mol 47.0339 ± 0.0010 61192-32-3*0 Hexafluorobenzene cation [C6F6]+ (g) 13.69 9.91 ± 0.87 kJ/mol 186.0541 ± 0.0048 34528-23-9*0 Hydrogen iodide HI (aq, 20 H2O) -55.08 ± 0.12 kJ/mol 127.912410 ± 0.000076 10034-85-2*818 Hydrogen bromide HBr (aq, 2000 H2O) -120.20 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*841 Formaldehyde CH2O (g, ortho singlet) -105.254 -109.220 ± 0.094 kJ/mol 30.02598 ± 0.00087 50-00-0*22 Dihydroxymethanide [CH(OH)2]- (g, syn-anti) -192.0 -201.3 ± 2.4 kJ/mol 47.0339 ± 0.0010 61192-32-3*1 Dihydroxymethanide [CH(OH)2]- (g, anti-anti) -177.6 -187.5 ± 2.4 kJ/mol 47.0339 ± 0.0010 61192-32-3*3 1,2-Butadiene CH3CHCCH2 (cr,l) 137.82 138.88 ± 0.63 kJ/mol 54.0904 ± 0.0032 590-19-2*500 2-Methoxy-2-oxoethyl CH2C(O)OCH3 (g) -202.9 -218.1 ± 1.5 kJ/mol 73.0706 ± 0.0025 54668-31-4*0 1-Hydroxyethenylium [CH2COH]+ (g) 841.7 834.9 ± 1.4 kJ/mol 43.0441 ± 0.0016 41084-89-3*0 Methylaminyliumyl [CH3N]+ (g ?) 1388.2 1381.9 ± 2.2 kJ/mol 29.04071 ± 0.00083 56924-51-7*0 Hypochlorous acid HOCl (aq) -110.484 ± 0.076 kJ/mol 52.46004 ± 0.00095 7790-92-3*800 (Acetyloxy)methyl CH3C(O)OCH2 (g) -200.1 -213.8 ± 1.5 kJ/mol 73.0706 ± 0.0025 2887-49-2*0 Hydrogen chloride HCl (aq, 300 H2O) -166.254 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*831 Hydroperoxonium [H2OOH]+ (g, cis) 762.6 752.7 ± 2.0 kJ/mol 35.02207 ± 0.00064 70850-26-9*2 (E)-Difluorodiazene cation [FNNF]+ (g, trans) 1307.4 1302.3 ± 3.7 kJ/mol 66.00974 ± 0.00014 *13776-62-0*1 Dioxymethylene HCOO (g) 341.8 339.8 ± 3.0 kJ/mol 45.0174 ± 0.0010 438586-67-5*0 Hydrogen iodide HI (aq, 700 H2O) -56.410 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*835 Acetic acid CH3C(O)OH (aq, 800 H2O) -484.79 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*837 Hydrogen bromide HBr (aq, 30 H2O) -118.58 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*820 Ammonium hydroxide NH4OH (aq, 555.1 H2O) -366.38 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*895 Acetic acid CH3C(O)OH (aq, 900 H2O) -484.79 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*838 Tetroxidane HOOOOH (g) -33.32 -43.26 ± 0.44 kJ/mol 66.0135 ± 0.0012 29683-94-1*0 Aminomethylidyne anion [CNH2]- (g, triplet) 481.6 478.1 ± 3.2 kJ/mol 28.03387 ± 0.00082 96808-04-7*1 Hydrogen iodide HI (aq, 800 H2O) -56.431 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*837 Furaniumyl [O(CHCHCHCH)]+ (g) 836.0 823.2 ± 1.3 kJ/mol 68.0734 ± 0.0032 66429-00-3*0 Furan anion [O(CHCHCHCH)]- (g) 132.1 120.8 ± 3.9 kJ/mol 68.0745 ± 0.0032 40807-44-1*0 2-Methyl-2-propanol (CH3)3COH (cr,l) -341.1 -365.5 ± 1.9 kJ/mol 74.1216 ± 0.0033 75-65-0*500 Fluorosyl fluoride cation [FFO]+ (g) 1413.1 1413.4 ± 3.5 kJ/mol 53.99566 ± 0.00030 *86825-50-5*0 Pyridiniumyl [N(CHCHCHCHCH)]+ (g) 1051.32 1035.37 ± 0.61 kJ/mol 79.0994 ± 0.0040 16399-94-3*0 Pyridine anion [N(CHCHCHCHCH)]- (g) 214.4 200.9 ± 3.2 kJ/mol 79.1005 ± 0.0040 12169-63-0*0 Chloromethylene CHCl (g) 320.36 320.65 ± 0.89 kJ/mol 48.4713 ± 0.0012 2108-20-5*0 Hydrogen iodide HI (aq, 111 H2O) -56.071 ± 0.095 kJ/mol 127.912410 ± 0.000076 10034-85-2*892 Hydroxymethoxy CH2(OH)O (g, anti) -149.9 -159.8 ± 1.8 kJ/mol 47.0333 ± 0.0010 72144-78-6*1 Hydroxymethoxy cation [CH2(OH)O]+ (g, triplet) 925.0 915.2 ± 3.2 kJ/mol 47.0328 ± 0.0010 180071-69-6*1 Acetone enol CH3C(OH)CH2 (g) -151.24 -168.05 ± 0.68 kJ/mol 58.0791 ± 0.0025 29456-04-0*0 Acetone enol CH3C(OH)CH2 (g, anti) -145.2 -162.5 ± 1.9 kJ/mol 58.0791 ± 0.0025 29456-04-0*2 Peroxyformic acid HC(O)OOH (g) -279.20 -288.33 ± 0.63 kJ/mol 62.0248 ± 0.0012 107-32-4*0 Tetroxidane HOOOOH (g, C2 II) -30.96 -41.42 ± 0.64 kJ/mol 66.0135 ± 0.0012 29683-94-1*23 Hydrogen bromide HBr (aq, 2500 H2O) -120.23 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*898 2-Hydroxyprop-1-en-1-yl CH3C(OH)CH (g) 101.65 90.29 ± 0.86 kJ/mol 57.0712 ± 0.0024 1976041-84-5*0 2-Hydroxyprop-1-en-1-yl CH3C(OH)CH (g, cis-cis) 106.6 94.6 ± 1.9 kJ/mol 57.0712 ± 0.0024 1976041-84-5*12 2-Hydroxyprop-1-en-1-yl CH3C(OH)CH (g, trans-trans) 114.0 102.9 ± 1.9 kJ/mol 57.0712 ± 0.0024 1976041-84-5*21 2-Hydroxyprop-1-en-1-yl CH3C(OH)CH (g, cis-trans) 115.1 104.3 ± 1.9 kJ/mol 57.0712 ± 0.0024 1976041-84-5*22 Hydroxymethoxy cation [CH2(OH)O]+ (g, triplet syn) 930.9 921.4 ± 3.7 kJ/mol 47.0328 ± 0.0010 180071-69-6*12 Hydrogen iodide HI (aq, 900 H2O) -56.448 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*838 Hydroxymethoxy cation [CH2(OH)O]+ (g, triplet anti) 933.5 923.8 ± 3.7 kJ/mol 47.0328 ± 0.0010 180071-69-6*11 Ammonium hydroxide NH4OH (aq, 600 H2O) -366.38 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*834 Ethylene anion [CH2CH2]- (g) 232.1 225.6 ± 2.0 kJ/mol 28.0537 ± 0.0016 34527-91-8*0 Hydroxymethoxy anion [CH2(OH)O]- (g) -373.82 -383.76 ± 0.85 kJ/mol 47.0339 ± 0.0010 67899-36-9*0 Nitric acid HON(O)O (aq, 30 H2O) -206.00 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*820 1-Oxopropyl CH3CH2CO (g) -19.1 -30.6 ± 1.1 kJ/mol 57.0712 ± 0.0024 15843-24-0*0 Hydrogen peroxide cation [HOOH]+ (g, cis, ortho) 931.09 924.21 ± 0.98 kJ/mol 34.01413 ± 0.00062 12325-10-9*21 1-Hydroxyethenylium [CH2COH]+ (g, syn-triplet) 1045.7 1038.7 ± 3.4 kJ/mol 43.0441 ± 0.0016 41084-89-3*12 Ammonium hydroxide NH4OH (aq, 700 H2O) -366.38 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*835 Hydroxymethoxy anion [CH2(OH)O]- (g, anti) -349.1 -358.7 ± 1.9 kJ/mol 47.0339 ± 0.0010 67899-36-9*1 1-Hydroxyethenyl anion [CH2COH]- (g) 15.1 8.6 ± 2.1 kJ/mol 43.0452 ± 0.0016 112539-13-6*0 Methyl nitrite CH3ONO (g, trans) -51.2 -63.2 ± 1.1 kJ/mol 61.0401 ± 0.0010 624-91-9*1 Methyl nitrite CH3ONO (cr,l) -87.57 ± 0.76 kJ/mol 61.0401 ± 0.0010 624-91-9*500 Hypoiodous acid cation [HOI]+ (g) 891.4 886.6 ± 3.3 kJ/mol 143.91126 ± 0.00031 193098-20-3*0 Hydrogen fluoride HF (aq, 22.2 H2O) -321.85 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*888 Ethyl nitrite CH3CH2ONO (g, gauche-trans) -78.9 -97.1 ± 1.9 kJ/mol 75.0666 ± 0.0017 109-95-5*2 Ethyl nitrite CH3CH2ONO (g, gauche-cis) -76.8 -95.7 ± 1.9 kJ/mol 75.0666 ± 0.0017 109-95-5*3 Ammonium hydroxide NH4OH (aq, 750 H2O) -366.38 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*836 Hydrogen bromide HBr (aq, 150 H2O) -119.66 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*829 Hydrogen bromide HBr (aq, 4000 H2O) -120.28 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*843 Propyl nitrite CH3CH2CH2ONO (g) -94.5 -118.3 ± 1.7 kJ/mol 89.0932 ± 0.0025 543-67-9*0 Propyl nitrite CH3CH2CH2ONO (g, trans-trans-cis) -94.2 -118.8 ± 2.4 kJ/mol 89.0932 ± 0.0025 543-67-9*2 Propyl nitrite CH3CH2CH2ONO (g, gauche-gauche-trans) -94.3 -118.9 ± 2.4 kJ/mol 89.0932 ± 0.0025 543-67-9*3 Propyl nitrite CH3CH2CH2ONO (g, gauche-gauche-trans II) -93.5 -118.1 ± 2.4 kJ/mol 89.0932 ± 0.0025 543-67-9*4 Propyl nitrite CH3CH2CH2ONO (g, trans-gauche-trans) -93.5 -117.8 ± 2.4 kJ/mol 89.0932 ± 0.0025 543-67-9*5 Propyl nitrite CH3CH2CH2ONO (g, trans-gauche-cis) -91.6 -116.6 ± 2.4 kJ/mol 89.0932 ± 0.0025 543-67-9*6 Propyl nitrite CH3CH2CH2ONO (g, gauche-gauche-cis) -91.3 -116.4 ± 2.4 kJ/mol 89.0932 ± 0.0025 543-67-9*7 Propyl nitrite CH3CH2CH2ONO (g, gauche-gauche-cis II) -89.9 -114.8 ± 2.7 kJ/mol 89.0932 ± 0.0025 543-67-9*8 2-Butynylium [CH3CCCH2]+ (g) 1085.9 1077.7 ± 1.3 kJ/mol 53.0820 ± 0.0032 64235-83-2*0 1-Methylethylidene CH3CCH3 (g) 316.08 303.18 ± 0.97 kJ/mol 42.0797 ± 0.0024 40852-89-9*0 Ammonium hydroxide NH4OH (aq, 6 H2O) -365.76 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*811 Glycine NH2CH2C(O)OH (g, anti-syn-syn) -373.80 -393.43 ± 0.80 kJ/mol 75.0666 ± 0.0017 56-40-6*2 Glycine NH2CH2C(O)OH (g, syn-perp-anti) -372.66 -390.70 ± 0.83 kJ/mol 75.0666 ± 0.0017 56-40-6*3 Glycine NH2CH2C(O)OH (g, syn-anti-syn) -370.19 -388.76 ± 0.80 kJ/mol 75.0666 ± 0.0017 56-40-6*4 Glycine NH2CH2C(O)OH (g, syn-perp-syn) -366.48 -385.23 ± 0.83 kJ/mol 75.0666 ± 0.0017 56-40-6*5 Glycine NH2CH2C(O)OH (g, anti-anti-anti) -358.01 -376.06 ± 0.83 kJ/mol 75.0666 ± 0.0017 56-40-6*6 Glycine NH2CH2C(O)OH (g, anti-anti-syn) -353.64 -368.93 ± 0.96 kJ/mol 75.0666 ± 0.0017 56-40-6*7 Glycine NH2CH2C(O)OH (g, anti-perp-anti) -352.9 -371.2 ± 1.0 kJ/mol 75.0666 ± 0.0017 56-40-6*8 Glycine cation [NH2CH2C(O)OH]+ (g) 520.3 501.8 ± 2.8 kJ/mol 75.0661 ± 0.0017 35492-82-1*0 Glycine cation [NH2CH2C(O)OH]+ (g, anti-syn) 554.2 536.1 ± 3.3 kJ/mol 75.0661 ± 0.0017 35492-82-1*2 Glycine cation [NH2CH2C(O)OH]+ (g, anti-anti) 555.1 537.7 ± 3.3 kJ/mol 75.0661 ± 0.0017 35492-82-1*3 Glycine cation [NH2CH2C(O)OH]+ (g, anti-perp) 557.1 539.4 ± 3.3 kJ/mol 75.0661 ± 0.0017 35492-82-1*4 Dioxoethylium [OCHCO]+ (g) 688.6 689.8 ± 2.9 kJ/mol 57.0276 ± 0.0017 *1994332-01-2*0 Glycine NH2CH2C(O)OH (cr, gamma) -508.34 -528.64 ± 0.23 kJ/mol 75.0666 ± 0.0017 56-40-6*513 Glycine NH2CH2C(O)OH (cr, beta) -508.04 -528.05 ± 0.22 kJ/mol 75.0666 ± 0.0017 56-40-6*512 Ethanedial anion [OCHCO]- (g) -188.8 -190.3 ± 3.1 kJ/mol 57.0287 ± 0.0017 1994332-01-2*0 Nitrous oxide NNO (aq, undissoc) 61.42 ± 0.11 kJ/mol 44.01288 ± 0.00033 10024-97-2*1000 Hydrogen bromide HBr (aq, 200 H2O) -119.75 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*830 Propynylidene HCCCH (g, singlet) 597.9 599.6 ± 1.2 kJ/mol 38.0480 ± 0.0024 67152-18-5*2 Glycine NH2CH2C(O)OH (aq, 20 H2O) -470.87 ± 0.21 kJ/mol 75.0666 ± 0.0017 56-40-6*818 Glycine NH2CH2C(O)OH (aq, 25 H2O) -470.76 ± 0.21 kJ/mol 75.0666 ± 0.0017 56-40-6*819 Glycine NH2CH2C(O)OH (aq, 30 H2O) -470.67 ± 0.21 kJ/mol 75.0666 ± 0.0017 56-40-6*820 Glycine NH2CH2C(O)OH (aq, 40 H2O) -470.57 ± 0.21 kJ/mol 75.0666 ± 0.0017 56-40-6*821 Glycine NH2CH2C(O)OH (aq, 50 H2O) -470.49 ± 0.21 kJ/mol 75.0666 ± 0.0017 56-40-6*822 Glycine NH2CH2C(O)OH (aq, 75 H2O) -470.37 ± 0.21 kJ/mol 75.0666 ± 0.0017 56-40-6*825 Glycine NH2CH2C(O)OH (aq, 100 H2O) -470.30 ± 0.21 kJ/mol 75.0666 ± 0.0017 56-40-6*828 Glycine NH2CH2C(O)OH (aq, 150 H2O) -470.23 ± 0.21 kJ/mol 75.0666 ± 0.0017 56-40-6*829 Glycine NH2CH2C(O)OH (aq, 200 H2O) -470.19 ± 0.21 kJ/mol 75.0666 ± 0.0017 56-40-6*830 Glycine NH2CH2C(O)OH (aq, 300 H2O) -470.16 ± 0.21 kJ/mol 75.0666 ± 0.0017 56-40-6*831 Glycine NH2CH2C(O)OH (aq, 400 H2O) -470.14 ± 0.21 kJ/mol 75.0666 ± 0.0017 56-40-6*832 Glycine NH2CH2C(O)OH (aq, 500 H2O) -470.13 ± 0.21 kJ/mol 75.0666 ± 0.0017 56-40-6*833 Glycine NH2CH2C(O)OH (aq, 700 H2O) -470.12 ± 0.21 kJ/mol 75.0666 ± 0.0017 56-40-6*835 Glycine NH2CH2C(O)OH (aq, 1000 H2O) -470.11 ± 0.21 kJ/mol 75.0666 ± 0.0017 56-40-6*839 Glycine NH2CH2C(O)OH (aq, 100000 H2O) -470.09 ± 0.21 kJ/mol 75.0666 ± 0.0017 56-40-6*861 Chlorine atom dianion [Cl]-2 (g) 406.6 408.2 ± 4.8 kJ/mol 35.45380 ± 0.00090 33944-49-9*0 Ammonium hydroxide NH4OH (aq, 800 H2O) -366.38 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*837 Carboxymethanaminium [NH3CH2C(O)OH]+ (g, syn-syn) 290.5 268.0 ± 1.5 kJ/mol 76.0740 ± 0.0018 *56-40-6*2 Carboxymethanaminium [NH3CH2C(O)OH]+ (g, anti-anti) 300.8 277.4 ± 1.5 kJ/mol 76.0740 ± 0.0018 *56-40-6*3 Carboxymethanaminium [NH3CH2C(O)OH]+ (aq) -518.21 ± 0.21 kJ/mol 76.0740 ± 0.0018 *56-40-6*800 Methylcarbamic acid CH3NHC(O)OH (g) -414.50 -432.75 ± 0.92 kJ/mol 75.0666 ± 0.0017 6414-57-9*0 Ammonium hydroxide NH4OH (aq, 900 H2O) -366.38 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*838 Methylcarbamic acid CH3NHC(O)OH (g, syn-syn) -408.6 -427.7 ± 2.0 kJ/mol 75.0666 ± 0.0017 6414-57-9*2 Methylcarbamic acid CH3NHC(O)OH (g, anti-anti) -385.8 -405.0 ± 2.0 kJ/mol 75.0666 ± 0.0017 6414-57-9*3 Methylcarbamic acid CH3NHC(O)OH (g, anti-syn) -380.6 -399.0 ± 2.0 kJ/mol 75.0666 ± 0.0017 6414-57-9*4 Chlorohydroxymethyl CH(Cl)OH (g) -54.7 -60.4 ± 1.1 kJ/mol 65.4787 ± 0.0012 147139-06-8*0 Carbamic acid NH2C(O)OH (g) -421.82 -435.04 ± 0.83 kJ/mol 61.0401 ± 0.0010 463-77-4*0 Carbamic acid NH2C(O)OH (g, anti) -392.9 -405.4 ± 1.9 kJ/mol 61.0401 ± 0.0010 463-77-4*2 Hydrogen chloride HCl (aq, 7000 H2O) -166.823 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*846 Ammonium hydroxide NH4OH (aq, 1500 H2O) -366.37 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*840 1,2-Dibromoethene CHBrCHBr (g) 124.7 104.5 ± 1.6 kJ/mol 185.8453 ± 0.0026 540-49-8*0 trans-1,2-Dibromoethene CHBrCHBr (g, trans) 124.2 104.4 ± 1.7 kJ/mol 185.8453 ± 0.0026 590-12-5*0 Hydroxyoxoethenylium [HOCCO]+ (g) 866.4 865.2 ± 3.5 kJ/mol 57.0276 ± 0.0017 *1994332-00-1*0 Hydrogen iodide HI (aq, 150 H2O) -56.134 ± 0.097 kJ/mol 127.912410 ± 0.000076 10034-85-2*829 Ethynediolide [HOCCO]- (g) -132.9 -134.0 ± 3.5 kJ/mol 57.0287 ± 0.0017 1994332-00-1*0 Cyanic fluoride cation [FCN]+ (g) 1294.2 1294.6 ± 1.1 kJ/mol 45.01529 ± 0.00080 62532-69-8*0 Acetylide [C2]-2 (g) 843.0 849.5 ± 3.2 kJ/mol 24.0225 ± 0.0016 34846-56-5*0 1,2-Diiodoethene CHICHI (g) 215.19 208.25 ± 0.35 kJ/mol 279.8462 ± 0.0016 20244-70-6*0 Cyclopropylidene C(CH2CH2) (g) 475.06 467.04 ± 0.84 kJ/mol 40.0639 ± 0.0024 2143-70-6*0 Ethylidene CH3CH (g) 361.31 354.32 ± 0.48 kJ/mol 28.0532 ± 0.0016 4218-50-2*0 Hydrogen chloride HCl (aq, 40 H2O) -164.927 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*821 Ammonium hydroxide NH4OH (aq, 1.5 H2O) -364.33 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*802 2,2,4-Trimethylpentane (CH3)2CHCH2C(CH3)3 (g) -171.1 -223.5 ± 1.5 kJ/mol 114.2285 ± 0.0065 540-84-1*0 Hydrogen iodide HI (aq, 1000 H2O) -56.464 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*839 Cyanogen chloride anion [ClCN]- (g) 46.8 51.2 ± 3.1 kJ/mol 61.4707 ± 0.0012 12281-43-5*0 Fluorosyl fluoride FFO (g) 192.8 193.3 ± 2.3 kJ/mol 53.99621 ± 0.00030 86825-57-2*0 Chloroethane CH3CH2Cl (cr,l) -134.33 -135.95 ± 0.25 kJ/mol 64.5138 ± 0.0019 75-00-3*500 Isocyanic acid anion [HNCO]- (g) -54.2 -57.4 ± 3.0 kJ/mol 43.02533 ± 0.00086 *444010-28-0*0 Ammonium hydroxide NH4OH (aq, 8 H2O) -365.92 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*813 Nitrilomethylimidogen NCHN (g) 581.6 578.4 ± 1.5 kJ/mol 41.03212 ± 0.00082 324529-58-0*0 Ethylperoxy CH3CH2OO (g) -6.09 -22.05 ± 0.60 kJ/mol 61.0599 ± 0.0017 3170-61-4*0 Iminomethylimidogen anion [NCHN]- (g) 401.9 400.0 ± 2.3 kJ/mol 41.03267 ± 0.00082 150296-30-3*0 Acetic acid CH3C(O)OH (aq, 1000 H2O) -484.80 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*839 1-Methylene-2-propenylium [CH2CHCCH2]+ (g) 1059.5 1049.4 ± 1.7 kJ/mol 53.0820 ± 0.0032 62698-26-4*0 1,1-Dibromoethane CH3CHBr2 (cr,l) -67.0 ± 1.3 kJ/mol 187.8612 ± 0.0026 557-91-5*500 Hydrogen chloride HCl (aq, 700 H2O) -166.488 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*835 Hydrogen bromide HBr (aq, 50 H2O) -119.10 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*822 Ammonium hydroxide NH4OH (aq, 2000 H2O) -366.35 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*841 (Methylamino)methyl anion [CH3NHCH2]- (g) 202.1 185.2 ± 3.1 kJ/mol 44.0763 ± 0.0017 *31277-25-5*0 3-Buten-2-one CH3C(O)CHCH2 (g) -95.28 -110.82 ± 0.85 kJ/mol 70.0898 ± 0.0032 78-94-4*0 Hydrogen fluoride HF (aq, 25 H2O) -321.87 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*819 3-Buten-2-one CH3C(O)CHCH2 (g, cis) -93.7 -109.7 ± 1.6 kJ/mol 70.0898 ± 0.0032 78-94-4*2 Trihydrogen cation [H3]+ (g, ortho) 1110.577 1106.695 ± 0.013 kJ/mol 3.02327 ± 0.00021 28132-48-1*1 1,3-Butadien-2-ol CH2C(OH)CHCH2 (g, s-trans, anti) -47.9 -64.2 ± 2.3 kJ/mol 70.0898 ± 0.0032 59120-04-6*12 Hydrogen bromide HBr (aq, 2 H2O) -92.66 ± 0.13 kJ/mol 80.9119 ± 0.0010 10035-10-6*803 1,3-Butadien-2-ol CH2C(OH)CHCH2 (g, s-cis, anti) -37.8 -54.2 ± 2.3 kJ/mol 70.0898 ± 0.0032 59120-04-6*22 Oxirene O(CHCH) (g) 272.44 270.29 ± 0.60 kJ/mol 42.0367 ± 0.0016 157-18-6*0 1,3-Butadien-2-ol CH2C(OH)CHCH2 (g, s-cis) -42.6 -58.6 ± 2.3 kJ/mol 70.0898 ± 0.0032 59120-04-6*2 1,3-Butadien-2-ol CH2C(OH)CHCH2 (g) -53.3 -68.2 ± 1.5 kJ/mol 70.0898 ± 0.0032 59120-04-6*0 Peroxyformyl HC(O)OO (g) -100.40 -105.50 ± 0.67 kJ/mol 61.0168 ± 0.0012 56240-83-6*0 1-Hydroxyethenyl anion [CH2COH]- (g, anti) 16.5 9.8 ± 2.7 kJ/mol 43.0452 ± 0.0016 112539-13-6*21 Hydrogen fluoride HF (aq, 7500 H2O) -324.98 ± 0.16 kJ/mol 20.006343 ± 0.000070 7664-39-3*847 Fluorine atom F (g, 2P1/2) 82.088 83.873 ± 0.017 kJ/mol 18.99840320 ± 0.00000050 14762-94-8*2 Hydrogen iodide HI (aq, 6 H2O) -49.962 ± 0.095 kJ/mol 127.912410 ± 0.000076 10034-85-2*811 Dioxyamidogen HNOO (g, trans) 251.1 244.6 ± 2.5 kJ/mol 47.01348 ± 0.00061 71843-95-3*1 Hydrodioxonitrate [HN(O)O]- (g) -61.9 -68.3 ± 3.1 kJ/mol 47.01403 ± 0.00061 61508-71-2*0 2-Methanidylidynehydrazin-2-ium-1-ide [HNNC]- (g, t-triplet) 531.7 530.3 ± 2.3 kJ/mol 41.03267 ± 0.00082 *947408-74-4*11 Acrolein cation [CH2CHCHO]+ (g) 920.02 910.06 ± 0.79 kJ/mol 56.0627 ± 0.0024 84005-05-0*0 Acrolein cation [CH2CHCHO]+ (g, cis) 930.9 921.0 ± 1.9 kJ/mol 56.0627 ± 0.0024 84005-05-0*2 Acrolein anion [CH2CHCHO]- (g) -71.8 -81.3 ± 3.1 kJ/mol 56.0638 ± 0.0024 23555-87-5*0 Acrolein anion [CH2CHCHO]- (g, trans) -67.9 -77.9 ± 3.5 kJ/mol 56.0638 ± 0.0024 23555-87-5*1 2-Cyclopropyn-1-ylidene C(CC) (g) 898.4 905.3 ± 1.5 kJ/mol 36.0321 ± 0.0024 102508-15-6*0 Difluorodioxidane anion [FOOF]- (g) -251. -251. ± 28. kJ/mol 69.99615 ± 0.00060 *7783-45-1*0 Ethoxyoxoniumylidene [CH3CH2OO]+ (g) 923.9 911.6 ± 1.5 kJ/mol 61.0594 ± 0.0017 268728-77-4*0 Nitric acid HON(O)O (aq, 50 H2O) -206.01 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*822 Propyn-1-ol cation [CH3CCOH]+ (g) 959.9 951.7 ± 3.0 kJ/mol 56.0627 ± 0.0024 84005-04-9*0 Peroxyformate [HC(O)OO]- (g) -340.93 -346.38 ± 0.80 kJ/mol 61.0174 ± 0.0012 104960-05-6*0 2-Methyloxirene CH3C(CHO) (g, triplet) 344.0 334.7 ± 1.8 kJ/mol 56.0633 ± 0.0024 2835-41-8*1 2-Methyloxirene CH3C(CHO) (g, c-triplet) 346.6 336.7 ± 2.5 kJ/mol 56.0633 ± 0.0024 2835-41-8*12 Difluorodinitrate [FNNF]- (g, trans) -207.8 -206.6 ± 4.7 kJ/mol 66.01083 ± 0.00014 37366-65-7*1 Dichlorine cation [Cl2]+ (g) 1108.307 1108.286 ± 0.0062 kJ/mol 70.9049 ± 0.0018 12595-90-3*0 Ethanimine CH3CHNH (g) 55.81 41.17 ± 0.72 kJ/mol 43.0678 ± 0.0016 20729-41-3*0 Ammonium hydroxide NH4OH (aq, 3000 H2O) -366.34 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*842 Acetic acid CH3C(O)OH (aq, 2000 H2O) -484.81 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*841 Acryloyl CH2CHCO (g) 101.2 96.4 ± 1.4 kJ/mol 55.0553 ± 0.0024 72241-20-4*0 Acryloyl CH2CHCO (g, 2A') 101.2 95.9 ± 1.4 kJ/mol 55.0553 ± 0.0024 72241-20-4*1 Acryloyl CH2CHCO (g, 2A', cis, TS?) 109.6 103.9 ± 5.7 kJ/mol 55.0553 ± 0.0024 72241-20-4*12 1-Oxo-2-propenylium [CH2CHCO]+ (g) 772.8 766.0 ± 3.0 kJ/mol 55.0548 ± 0.0024 35335-83-2*0 1-Oxo-2-propenylium [CH2CHCO]+ (g, triplet) 1036.1 1030.7 ± 3.9 kJ/mol 55.0548 ± 0.0024 35335-83-2*1 1-Oxo-2-propenide [CH2CHCO]- (g) 50.7 46.0 ± 2.6 kJ/mol 55.0559 ± 0.0024 78944-75-9*0 Ethoxyoxoniumylidene [CH3CH2OO]+ (g, singlet) 962.5 947.8 ± 1.6 kJ/mol 61.0594 ± 0.0017 268728-77-4*2 Ethoxyoxoniumylidene [CH3CH2OO]+ (g, gauche singlet) 967.6 951.7 ± 2.4 kJ/mol 61.0594 ± 0.0017 268728-77-4*23 Hydrogen chloride HCl (aq, 800 H2O) -166.517 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*837 1-Formylethenylium [CH2CCHO]+ (g) 1023.5 1018.0 ± 2.3 kJ/mol 55.0548 ± 0.0024 101705-89-9*0 Propargylenide [HCCCH]- (g) 434.5 437.7 ± 1.1 kJ/mol 38.0485 ± 0.0024 82906-05-6*0 Hypochloroperoxoous acid, hydroxy ester HOOOCl (g) 48.4 41.6 ± 1.8 kJ/mol 84.4588 ± 0.0013 928652-99-7*0 Ethaneperoxolate [CH3CH2OO]- (g) -120.32 -136.38 ± 0.68 kJ/mol 61.0604 ± 0.0017 268728-75-2*0 Hydrogen fluoride HF (aq, 264.3 H2O) -322.13 ± 0.10 kJ/mol 20.006343 ± 0.000070 7664-39-3*909 3-Oxo-1-propenyl CHCHCHO (g) 190.97 185.43 ± 0.91 kJ/mol 55.0553 ± 0.0024 206255-29-0*0 Difluorodioxidanium [FOOF]+ (g) 1283.7 1280.1 ± 2.3 kJ/mol 69.99506 ± 0.00060 *7783-44-0*0 3-Oxo-1-propenyl CHCHCHO (g, cis) 191.7 185.9 ± 2.1 kJ/mol 55.0553 ± 0.0024 206255-29-0*2 Acetic acid CH3C(O)OH (aq, 7 H2O) -483.35 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*812 3-Oxo-1-propenyl CHCHCHO (g, syn-cis) 201.4 195.5 ± 2.0 kJ/mol 55.0553 ± 0.0024 206255-29-0*22 3-Oxo-1-propenyl CHCHCHO (g, syn-trans) 206.1 200.2 ± 2.0 kJ/mol 55.0553 ± 0.0024 206255-29-0*12 3-Oxo-1-propenylium [CHCHCHO]+ (g) 1005.1 1002.8 ± 2.4 kJ/mol 55.0548 ± 0.0024 101705-90-2*0 3-Oxo-1-propenylium [CHCHCHO]+ (g, triplet) 1185.6 1180.0 ± 3.0 kJ/mol 55.0548 ± 0.0024 101705-90-2*1 Cyanic acid cation [HOCN]+ (g) 1135.7 1133.2 ± 2.9 kJ/mol 43.02423 ± 0.00086 59780-31-3*0 3-Oxo-1-propenylium [CHCHCHO]+ (g, trans-triplet) 1185.6 1179.9 ± 3.0 kJ/mol 55.0548 ± 0.0024 101705-90-2*11 3-Oxo-1-propenylium [CHCHCHO]+ (g, cis-triplet) 1197.7 1192.4 ± 3.4 kJ/mol 55.0548 ± 0.0024 101705-90-2*12 1,3-Butadiyne-1,4-diyl CCCC (g, singlet) 1083.98 1093.79 ± 0.83 kJ/mol 48.0428 ± 0.0032 78015-07-3*2 3-Oxo-1-propenylium [CHCHCHO]+ (g, syn-trans-triplet) 1195.7 1189.8 ± 3.4 kJ/mol 55.0548 ± 0.0024 101705-90-2*112 3-Oxo-1-propenylium [CHCHCHO]+ (g, syn-cis-triplet) 1205.8 1200.3 ± 3.8 kJ/mol 55.0548 ± 0.0024 101705-90-2*122 2-Formylethen-1-ide [CHCHCHO]- (g) 27.4 21.4 ± 2.5 kJ/mol 55.0559 ± 0.0024 135924-69-5*0 2-Formylethen-1-ide [CHCHCHO]- (g, trans) 27.4 20.6 ± 2.5 kJ/mol 55.0559 ± 0.0024 135924-69-5*1 2-Formylethen-1-ide [CHCHCHO]- (g, cis) 30.5 23.8 ± 3.1 kJ/mol 55.0559 ± 0.0024 135924-69-5*2 Oxirene O(CHCH) (g, triplet) 387.8 384.4 ± 1.3 kJ/mol 42.0367 ± 0.0016 157-18-6*1 2-Formylethen-1-ide [CHCHCHO]- (g, syn-cis) 54.6 47.9 ± 3.1 kJ/mol 55.0559 ± 0.0024 135924-69-5*22 2-Formylethen-1-ide [CHCHCHO]- (g, syn-trans) 65.0 58.5 ± 3.1 kJ/mol 55.0559 ± 0.0024 135924-69-5*12 Propylidene anion [CH3CH2CH]- (g) 300.9 286.7 ± 3.2 kJ/mol 42.0803 ± 0.0024 *121408-55-7*0 1,2-Propadien-1-one anion [CH2CCO]- (g) 49.8 48.6 ± 3.1 kJ/mol 54.0479 ± 0.0024 159171-62-7*0 Hydrogen chloride HCl (aq, 150 H2O) -165.978 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*829 Pentachloroethylium [CCl3CCl2]+ (g) 838.1 836.5 ± 3.3 kJ/mol 201.2844 ± 0.0048 *7094-17-9*0 Ethylideneammoniumylidene [CH3CHN]+ (g, triplet) 1310.0 1300.4 ± 3.0 kJ/mol 42.0594 ± 0.0016 91127-36-5*1 1-Oxo-2-propyn-1-ylium [HCCCO]+ (g) 1001.7 1003.2 ± 3.0 kJ/mol 53.0389 ± 0.0024 53474-99-0*0 3-Oxo-1,2-propadien-1-yl anion [HCCCO]- (g) 179.4 182.1 ± 3.2 kJ/mol 53.0400 ± 0.0024 557113-97-0*0 Nitric acid HON(O)O (aq, 55.51 H2O) -206.01 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*891 Pentachloroethanide [CCl3CCl2]- (g) -281.7 -280.3 ± 3.9 kJ/mol 201.2854 ± 0.0048 263019-83-6*0 O--HH Complex (H2)(O) (g, vdW C2v ?) 247.2 248.2 ± 2.0 kJ/mol 18.01528 ± 0.00033 *7732-18-5*102 Formylethynyl anion [CCCHO]- (g) 100.5 101.9 ± 3.4 kJ/mol 53.0400 ± 0.0024 85905-64-2*0 Nitric acid HON(O)O (aq, 100 H2O) -206.02 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*828 2-Cyclopropen-1-one cation [OC(CHCH)]+ (g) 1078.8 1075.7 ± 2.0 kJ/mol 54.0468 ± 0.0024 100815-68-7*0 Ethylideneazanide [CH3CHN]- (g) 147.8 137.6 ± 3.2 kJ/mol 42.0604 ± 0.0016 144810-43-5*0 Hydrazine anion [NH2NH2]- (g) 232.3 218.0 ± 4.1 kJ/mol 32.04579 ± 0.00031 65391-88-0*0 Ethaneperoxolate [CH3CH2OO]- (g, trans) -119.8 -135.4 ± 1.9 kJ/mol 61.0604 ± 0.0017 268728-75-2*1 Hypoiodous acid HOI (aq) -116.3 ± 5.4 kJ/mol 143.91181 ± 0.00031 14332-21-9*800 Oxide [O]-2 (g) 651. 653. ± 15. kJ/mol 16.00050 ± 0.00030 16833-27-5*0 Isourea NHC(OH)NH2 (g) -156.1 -172.7 ± 2.6 kJ/mol 60.05534 ± 0.00091 4744-36-9*0 Acetic acid CH3C(O)OH (aq, 8 H2O) -483.43 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*813 Hydrogen fluoride HF (aq, 500000 H2O) -333.04 ± 0.16 kJ/mol 20.006343 ± 0.000070 7664-39-3*866 Carbamoyl anion [NH2CO]- (g) -81.9 -87.8 ± 3.1 kJ/mol 44.03327 ± 0.00087 78944-69-1*0 Ethynol cation [HCCOH]+ (g) 1063.8 1061.2 ± 2.9 kJ/mol 42.0361 ± 0.0016 84005-02-7*0 Carbamoyl HNCOH (g) 74.1 68.3 ± 2.7 kJ/mol 44.03272 ± 0.00087 *2858-51-7*0 Carbamoyl HNCOH (g, trans-cis) 76.5 69.9 ± 3.2 kJ/mol 44.03272 ± 0.00087 *2858-51-7*2 Carbamoyl HNCOH (g, cis-trans) 96.4 90.1 ± 3.2 kJ/mol 44.03272 ± 0.00087 *2858-51-7*3 Carbamoyl HNCOH (g, cis-cis) 110.9 104.8 ± 3.2 kJ/mol 44.03272 ± 0.00087 *2858-51-7*4 Acetic acid CH3C(O)OH (aq, 5000 H2O) -484.69 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*844 Cyanic fluoride anion [FCN]- (g) -20.7 -18.7 ± 2.9 kJ/mol 45.01639 ± 0.00080 34507-50-1*0 Hydrogen chloride HCl (aq, 10000 H2O) -166.848 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*850 (Hydroxyimino)methyl HCNOH (g) 250.2 244.4 ± 1.8 kJ/mol 44.03272 ± 0.00087 206442-92-4*0 2-Hydroxyethenyl CHCHOH (g) 138.01 132.19 ± 0.72 kJ/mol 43.0446 ± 0.0016 108665-16-3*0 Hydrogen bromide HBr (aq, 1 H2O) -71.66 ± 0.13 kJ/mol 80.9119 ± 0.0010 10035-10-6*801 (Hydroxyimino)methyl HCNOH (g, cis-trans) 262.6 257.2 ± 2.5 kJ/mol 44.03272 ± 0.00087 206442-92-4*3 (Hydroxyimino)methyl HCNOH (g, cis-cis) 281.4 276.0 ± 2.5 kJ/mol 44.03272 ± 0.00087 206442-92-4*4 Acetic acid CH3C(O)OH (aq, 9 H2O) -483.51 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*814 Formamide enol NHCHOH (g) -130.6 -141.6 ± 1.3 kJ/mol 45.04066 ± 0.00088 60100-09-6*0 Nitric acid HON(O)O (aq, 500 H2O) -206.14 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*833 Formamide enol NHCHOH (g, anti-anti) -116.6 -127.6 ± 2.1 kJ/mol 45.04066 ± 0.00088 60100-09-6*2 Formamide enol NHCHOH (g, syn-anti) -115.9 -126.6 ± 2.1 kJ/mol 45.04066 ± 0.00088 60100-09-6*3 Formamide enol NHCHOH (g, syn-syn) -109.8 -120.6 ± 2.1 kJ/mol 45.04066 ± 0.00088 60100-09-6*4 Diazene cation [HNNH]+ (g, trans-iso-cis equilib) 1132.53 1125.87 ± 0.64 kJ/mol 30.02881 ± 0.00020 76986-17-9*0 Aminohydroxymethylene NH2COH (g) -22.4 -33.0 ± 1.6 kJ/mol 45.04066 ± 0.00088 160720-48-9*0 Aminohydroxymethylene NH2COH (g, singlet) -22.4 -33.0 ± 1.6 kJ/mol 45.04066 ± 0.00088 160720-48-9*2 Aminohydroxymethylene NH2COH (g, syn-singlet) 1.7 -8.9 ± 2.3 kJ/mol 45.04066 ± 0.00088 160720-48-9*22 Aminohydroxymethylene NH2COH (g, triplet) 217.2 209.7 ± 3.0 kJ/mol 45.04066 ± 0.00088 160720-48-9*1 1H-Diazirin-3-ylium [HN(NC)]+ (g) 1527.2 1523.7 ± 2.0 kJ/mol 41.03157 ± 0.00082 735234-64-7*0 Aminohydroxymethylene NH2COH (g, gauche-triplet) 220.1 211.4 ± 3.4 kJ/mol 45.04066 ± 0.00088 160720-48-9*12 Peroxychlorite [OClOO]- (g) -116.2 -114.9 ± 2.3 kJ/mol 83.4514 ± 0.0013 852472-63-0*0 2-Iminoethyl CH2CHNH (g) 219.37 208.69 ± 0.86 kJ/mol 42.0599 ± 0.0016 73843-90-0*0 Ammonium hydroxide NH4OH (aq, 4000 H2O) -366.32 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*843 1,2-Butadienylium [CH3CHCCH]+ (g) 1099.2 1089.9 ± 1.2 kJ/mol 53.0820 ± 0.0032 *65114-67-2*0 Formaldoxime CH2NOH (g) 30.6 20.0 ± 1.3 kJ/mol 45.04066 ± 0.00088 75-17-2*0 O--HH Complex (H2)(O) (g, vdW Cinfv ?) 247.7 249.0 ± 2.7 kJ/mol 18.01528 ± 0.00033 *7732-18-5*101 Hydrogen bromide HBr (aq, 10 H2O) -115.90 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*815 1,2-Dichloroethene CHClCHCl (g) 3.83 -1.49 ± 0.55 kJ/mol 96.9427 ± 0.0024 540-59-0*0 Hydrogen chloride HCl (aq, 20000 H2O) -166.886 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*852 Hydrogen bromide HBr (aq, 300 H2O) -119.86 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*831 Nitric acid HON(O)O (aq, 555.1 H2O) -206.14 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*895 Nitric acid HON(O)O (aq, 2000 H2O) -206.27 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*841 Hydrogen chloride HCl (aq, 55.51 H2O) -165.294 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*891 Acetic acid CH3C(O)OH (aq, 10000 H2O) -484.83 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*850 1-Hydroperoxyethylium [CH3CHOOH]+ (g) 690.7 675.8 ± 1.5 kJ/mol 61.0594 ± 0.0017 *126898-98-4*0 Hydrogen fluoride HF (aq, 75 H2O) -321.99 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*825 Acetic acid CH3C(O)OH (aq, 20000 H2O) -484.84 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*852 2-Iminoethylium [CH2CHNH]+ (g) 1108.4 1097.7 ± 2.9 kJ/mol 42.0594 ± 0.0016 73843-91-1*0 Hydrogen iodide HI (aq, 1250 H2O) -56.494 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*954 Nitric acid HON(O)O (aq, 5000 H2O) -206.34 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*844 Acetic acid CH3C(O)OH (aq, 50000 H2O) -484.85 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*855 Nitric acid HON(O)O (aq, 10000 H2O) -206.39 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*850 2-Iminoethylium [CH2CHNH]+ (g, triplet) 1148.7 1140.2 ± 3.3 kJ/mol 42.0594 ± 0.0016 73843-91-1*1 1-Cyanoethylidene CH3CCN (g) 437.6 433.8 ± 1.4 kJ/mol 53.0627 ± 0.0024 498544-34-6*0 Hydrogen iodide HI (aq, 1500 H2O) -56.519 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*840 Oxooxoniumylmethoxy [OC(O)O]+ (g) 1178.0 1177.3 ± 5.7 kJ/mol 60.0084 ± 0.0012 952586-28-6*0 Cyanic acid anion [HOCN]- (g) -9.2 -9.5 ± 3.1 kJ/mol 43.02533 ± 0.00086 58199-47-6*0 Propadienylidene CH2CC (g, triplet) 678.34 679.32 ± 0.41 kJ/mol 38.0480 ± 0.0024 60731-10-4*1 Dichlorovinylidene CCCl2 (g) 424.4 427.6 ± 3.0 kJ/mol 94.9268 ± 0.0024 20394-25-6*0 Diazene cation [HNNH]+ (g, trans-cis equilib) 1132.53 1125.60 ± 0.64 kJ/mol 30.02881 ± 0.00020 76986-17-9*1 1-Hydroperoxyethylium [CH3CHOOH]+ (g, triplet) 841.6 830.3 ± 1.7 kJ/mol 61.0594 ± 0.0017 *126898-98-4*1 3-Imino-2-propen-1-ylidene CHCHCNH (g) 530.7 526.4 ± 1.2 kJ/mol 53.0627 ± 0.0024 916765-05-4*0 Chlorovinylidene CCHCl (g) 429.3 431.0 ± 2.9 kJ/mol 60.4820 ± 0.0018 70277-82-6*0 3-Imino-2-propen-1-ylidene CHCHCNH (g, triplet) 571.9 567.1 ± 1.6 kJ/mol 53.0627 ± 0.0024 916765-05-4*2 Nitrogen sesquioxide cation [ONN(O)O]+ (g, vdW) 1027.6 1023.7 ± 4.8 kJ/mol 76.01113 ± 0.00091 *10544-73-7*0 1-Hydroperoxyethylium [CH3CHOOH]+ (g, cis singlet) 692.0 676.3 ± 2.3 kJ/mol 61.0594 ± 0.0017 *126898-98-4*22 Hydrogen fluoride HF (aq, 5000 H2O) -324.43 ± 0.14 kJ/mol 20.006343 ± 0.000070 7664-39-3*844 1-Hydroperoxyethylium [CH3CHOOH]+ (g, cis triplet) 843.8 831.8 ± 2.6 kJ/mol 61.0594 ± 0.0017 *126898-98-4*12 2-(Methylidyneamino)ethenyl CHCHNCH (g) 600.7 596.4 ± 1.2 kJ/mol 53.0627 ± 0.0024 123416-74-0*0 1H-diazirin-3-ide [HN(NC)]- (g) 379.8 376.7 ± 2.0 kJ/mol 41.03267 ± 0.00082 *735234-64-7*0 2-(Methylidyneamino)ethenyl CHCHNCH (g, triplet) 634.5 630.5 ± 1.6 kJ/mol 53.0627 ± 0.0024 123416-74-0*2 Bromine atom Br (g, 2P1/2) 162.009 155.947 ± 0.055 kJ/mol 79.90400 ± 0.00100 10097-32-2*2 Hydrogen bromide HBr (aq, 400 H2O) -119.92 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*832 Carbonylbis(oxy) OC(O)O (g) -144.7 -145.7 ± 2.4 kJ/mol 60.0089 ± 0.0012 16518-45-9*0 Tetraiodomethane CI4 (cr, monoclinic) 238. ± 10. kJ/mol 519.62858 ± 0.00081 507-25-5*500 Ethynol anion [HCCOH]- (g) 163.5 165.0 ± 3.3 kJ/mol 42.0372 ± 0.0016 864971-50-6*0 Methylaminyliumyl [CH3N]+ (g, quartet) 1423.0 1416.0 ± 2.2 kJ/mol 29.04071 ± 0.00083 56924-51-7*2 Propylidene CH3CH2CH (g) 349.52 335.83 ± 0.92 kJ/mol 42.0797 ± 0.0024 6700-78-3*0 Hydrogen iodide HI (aq, 2000 H2O) -56.552 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*841 Hydrogen bromide HBr (aq, 7000 H2O) -120.33 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*846 1,3-Propanediyl CH2CH2CH2 (g, triplet) 319.3 307.9 ± 1.3 kJ/mol 42.0797 ± 0.0024 32458-33-6*1 1,3-Butadienyl CH2CHCHCH (g) 372.30 363.08 ± 0.87 kJ/mol 53.0825 ± 0.0032 86181-68-2*0 1,3-Butadienyl CH2CHCHCH (g, trans-cis) 374.9 364.5 ± 1.9 kJ/mol 53.0825 ± 0.0032 86181-68-2*12 Carbonate [OC(O)O]-2 (aq) -675.162 ± 0.053 kJ/mol 60.0100 ± 0.0012 3812-32-6*800 2-Cyanovinyl CHCHCN (g) 447.86 445.45 ± 0.98 kJ/mol 52.0547 ± 0.0024 189141-20-6*0 2-Cyanovinylium [CHCHCN]+ (g, triplet) 1517.3 1515.2 ± 1.8 kJ/mol 52.0542 ± 0.0024 85398-67-0*2 2-Cyanovinyl anion [CHCHCN]- (g) 263.8 261.5 ± 1.8 kJ/mol 52.0553 ± 0.0024 *85398-67-0*0 2-Iminoethyl anion [CH2CHNH]- (g) 104.5 94.1 ± 2.1 kJ/mol 42.0604 ± 0.0016 73843-87-5*0 1,3-Butadienyl CH2CHCHCH (g, cis-trans) 384.1 374.5 ± 1.9 kJ/mol 53.0825 ± 0.0032 86181-68-2*21 2-Isocyanovinyl CHCHNC (g) 543.3 541.8 ± 1.7 kJ/mol 52.0547 ± 0.0024 225798-14-1*0 Hydrogen iodide HI (aq, 25 H2O) -55.35 ± 0.11 kJ/mol 127.912410 ± 0.000076 10034-85-2*819 1,3-Butadienyl CH2CHCHCH (g, gauche-cis) 385.6 375.4 ± 1.9 kJ/mol 53.0825 ± 0.0032 86181-68-2*22 Cyanomethyliumyl [HCCN]+ (g) 1506.4 1508.0 ± 2.3 kJ/mol 39.0355 ± 0.0016 34447-38-6*0 Cyanomethylene anion [HCCN]- (g) 286.3 286.8 ± 1.5 kJ/mol 39.0366 ± 0.0016 12373-24-9*0 Cyanomethylene HCCN (g) 479.6 483.0 ± 1.1 kJ/mol 39.0361 ± 0.0016 2612-62-6*0 Nitric acid HON(O)O (aq, 50000 H2O) -206.46 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*855 1,3-Butadienylium [CH2CHCHCH]+ (g) 1133.7 1123.7 ± 2.5 kJ/mol 53.0820 ± 0.0032 86181-69-3*0 Isocyanomethyliumyl [HCNC]+ (g) 1506.7 1508.6 ± 3.2 kJ/mol 39.0355 ± 0.0016 99045-54-2*0 Isocyanomethylene anion [HCNC]- (g) 401.4 402.1 ± 2.0 kJ/mol 39.0366 ± 0.0016 144141-01-5*0 Isocyanomethylene HCNC (g) 583.1 585.3 ± 1.6 kJ/mol 39.0361 ± 0.0016 78694-65-2*0 2-Hydroperoxyethyl CH2CH2OOH (g) 64.8 51.4 ± 1.3 kJ/mol 61.0599 ± 0.0017 126898-97-3*0 3-Oxo-1,2-propadien-1-ylium-1-yl [CCCO]+ (g) 1380.4 1385.7 ± 3.8 kJ/mol 52.0310 ± 0.0024 151455-13-9*0 3-Oxo-1,2-propadienylidene anion [CCCO]- (g) 224.4 230.2 ± 3.5 kJ/mol 52.0320 ± 0.0024 109292-50-4*0 Fluoromethane cation [CH3F]+ (g) 981.82 974.32 ± 0.62 kJ/mol 34.03237 ± 0.00083 59122-96-2*0 Hydrogen bromide HBr (aq, 55.51 H2O) -119.18 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*891 2-Hydroperoxyethyl CH2CH2OOH (g, gauche) 64.8 51.0 ± 1.3 kJ/mol 61.0599 ± 0.0017 126898-97-3*3 Fluoromethane CH3F (l) -251.65 ± 0.25 kJ/mol 34.03292 ± 0.00083 593-53-3*590 Ethynylamidogen anion [HCCNH]- (g) 233.7 230.5 ± 3.2 kJ/mol 40.0446 ± 0.0016 64066-03-1*0 Trioxidaniumyl [HOOOH]+ (g) 925.5 916.6 ± 1.4 kJ/mol 50.01353 ± 0.00091 161321-37-5*0 Water dimer cation [(H2O)2]+ (g) 557.2 546.8 ± 3.0 kJ/mol 36.03001 ± 0.00066 158061-35-9*0 Hydrogen fluoride HF (aq, 15 H2O) -321.78 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*817 2-Hydroperoxyethyl CH2CH2OOH (g, anti) 65.2 51.8 ± 2.2 kJ/mol 61.0599 ± 0.0017 126898-97-3*1 Peroxychlorous acid HOOClO (g) 95.4 89.8 ± 2.0 kJ/mol 84.4588 ± 0.0013 177778-92-6*0 Hydrogen chloride HCl (aq, 50000 H2O) -166.923 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*855 1,3-Cyclobutadiene cation [CH(CHCHCH)]+ (g) 1215.6 1207.2 ± 3.0 kJ/mol 52.0740 ± 0.0032 34531-09-4*0 1-Iminoethyl CH3CNH (g) 233.1 223.0 ± 1.1 kJ/mol 42.0599 ± 0.0016 128365-64-0*0 1-Iminoethyl CH3CNH (g, syn) 252.4 242.4 ± 2.0 kJ/mol 42.0599 ± 0.0016 128365-64-0*1 2-Methyl-2-cyclopropen-1-ylidene CH3C(CHC) (g) 448.1 441.9 ± 1.2 kJ/mol 52.0746 ± 0.0032 185841-59-2*0 2-Methyl-2-cyclopropen-1-ylidene CH3C(CHC) (g, triplet) 670.7 664.7 ± 2.8 kJ/mol 52.0746 ± 0.0032 185841-59-2*1 Chloromethane CH3Cl (l) -106.44 -102.47 ± 0.17 kJ/mol 50.4872 ± 0.0012 74-87-3*590 Bromomethane cation [CH3Br]+ (g) 996.66 981.75 ± 0.20 kJ/mol 94.9380 ± 0.0013 12538-70-4*0 1-Iminoethylium [CH3CNH]+ (g) 833.7 823.2 ± 3.0 kJ/mol 42.0594 ± 0.0016 *128365-64-0*0 1-Iminoethylium [CH3CNH]+ (g, triplet) 1342.2 1333.3 ± 3.9 kJ/mol 42.0594 ± 0.0016 *128365-64-0*1 Propylidene CH3CH2CH (g, singlet TS syn) 362.8 347.5 ± 2.8 kJ/mol 42.0797 ± 0.0024 6700-78-3*22 2-Hydroperoxyethyl CH2CH2OOH (g, gauche-anti) 65.7 51.7 ± 2.2 kJ/mol 61.0599 ± 0.0017 126898-97-3*31 Vinylvinylidene CH2CHCHC (g) 494.2 488.8 ± 1.7 kJ/mol 52.0746 ± 0.0032 148759-16-4*0 Vinylvinylidene CH2CHCHC (g, triplet) 690.5 684.7 ± 2.6 kJ/mol 52.0746 ± 0.0032 148759-16-4*1 Hydrogen bromide HBr (aq, 75 H2O) -119.36 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*825 Vinylvinylidene CH2CHCHC (g, triplet, cis) 695.5 689.0 ± 3.3 kJ/mol 52.0746 ± 0.0032 148759-16-4*12 Vinylvinylidene cation [CH2CHCHC]+ (g) 1429.9 1424.6 ± 2.0 kJ/mol 52.0740 ± 0.0032 161054-20-2*0 Vinylvinylidene cation [CH2CHCHC]+ (g, cis) 1437.9 1432.3 ± 2.7 kJ/mol 52.0740 ± 0.0032 161054-20-2*2 Vinylvinylidene anion [CH2CHCHC]- (g) 405.8 399.0 ± 2.0 kJ/mol 52.0751 ± 0.0032 167386-49-4*0 Vinylvinylidene anion [CH2CHCHC]- (g, cis) 423.3 416.7 ± 2.7 kJ/mol 52.0751 ± 0.0032 167386-49-4*2 2-Hydroperoxyethyl CH2CH2OOH (g, anti-syn) 65.8 52.1 ± 2.2 kJ/mol 61.0599 ± 0.0017 126898-97-3*12 Acetic acid CH3C(O)OH (aq, 10 H2O) -483.59 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*815 1,2-Butadien-1-ylidene CH3CHCC (g) 511.8 506.3 ± 2.0 kJ/mol 52.0746 ± 0.0032 119908-55-3*0 1,2-Butadien-1-ylidene CH3CHCC (g, triplet) 651.8 646.3 ± 3.7 kJ/mol 52.0746 ± 0.0032 119908-55-3*1 Ethenyldioxy CH2CHOO (g) 118.42 109.52 ± 0.99 kJ/mol 59.0440 ± 0.0017 88181-72-0*0 1-Iminoethylium [CH3CNH]+ (g, syn-triplet) 1378.3 1368.8 ± 4.3 kJ/mol 42.0594 ± 0.0016 *128365-64-0*11 Ethenyldioxy CH2CHOO (g, syn) 122.6 112.9 ± 2.0 kJ/mol 59.0440 ± 0.0017 88181-72-0*2 Iodomethane cation [CH3I]+ (g) 944.82 935.42 ± 0.16 kJ/mol 141.93844 ± 0.00083 12538-72-6*0 Diazene HNNH (g, trans-cis-iso equilib) 207.17 200.03 ± 0.40 kJ/mol 30.02936 ± 0.00020 3618-05-1*0 Fluorosyl fluoride anion [FFO]- (g) -147.1 -146.8 ± 3.0 kJ/mol 53.99675 ± 0.00030 *86825-57-2*0 Hydrogen bromide HBr (aq, 10000 H2O) -120.36 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*850 1-Iminoethanide [CH3CNH]- (g) 185.7 175.6 ± 3.2 kJ/mol 42.0604 ± 0.0016 *128365-65-1*0 Fluoroform CHF3 (l) -704.70 ± 0.42 kJ/mol 70.01385 ± 0.00080 75-46-7*590 1,2,3-Butatrien-1-ylium [CH2CCCH]+ (g) 1271.9 1270.1 ± 1.1 kJ/mol 51.0661 ± 0.0032 81932-79-8*0 Hydrogen bromide HBr (aq, 20000 H2O) -120.40 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*852 Hydrogen peroxide cation [HOOH]+ (g, trans, para) 897.32 890.32 ± 0.51 kJ/mol 34.01413 ± 0.00062 12325-10-9*12 2-Hydroxyethylium [CH2CH2OH]+ (g) 1019.3 1007.2 ± 1.5 kJ/mol 45.0600 ± 0.0017 38607-31-7*0 1-Iminoethanide [CH3CNH]- (g, syn) 193.2 182.6 ± 3.6 kJ/mol 42.0604 ± 0.0016 *128365-65-1*1 Isofulminic acid cation [HONC]+ (g) 1377.0 1374.9 ± 2.9 kJ/mol 43.02423 ± 0.00086 117800-60-9*0 Acetic acid CH3C(O)OH (aq, 100000 H2O) -484.86 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*861 1-Buten-3-yn-1-yl HCCCHCH (g) 547.40 544.88 ± 0.84 kJ/mol 51.0666 ± 0.0032 2810-61-9*0 1-Buten-3-ynylium [HCCCHCH]+ (g) 1482.5 1480.3 ± 1.4 kJ/mol 51.0661 ± 0.0032 84654-85-3*0 But-1-en-3-yn-1-ide [HCCCHCH]- (g) 419.9 419.2 ± 1.2 kJ/mol 51.0672 ± 0.0032 119611-65-3*0 Hydrogen bromide HBr (aq, 50000 H2O) -120.43 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*855 Hydrogen chloride HCl (aq, 20 H2O) -163.676 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*818 Isocyanogen chloride anion [ClNC]- (g) 102.9 107.4 ± 3.9 kJ/mol 61.4707 ± 0.0012 923019-39-0*0 Hypobromous acid cation [HOBr]+ (g) 975.25 964.63 ± 0.54 kJ/mol 96.9108 ± 0.0010 154804-02-1*0 Iodotrifluoromethane cation [CF3I]+ (g) 412.8 407.5 ± 2.6 kJ/mol 195.90983 ± 0.00080 64626-54-6*0 3-Buten-1-ynylium [CH2CHCC]+ (g) 1572.7 1570.3 ± 1.7 kJ/mol 51.0661 ± 0.0032 103928-84-3*0 But-3-en-1-yn-1-ide [CH2CHCC]- (g) 326.8 323.7 ± 1.3 kJ/mol 51.0672 ± 0.0032 58870-47-6*0 Hydrogen iodide HI (aq, 2500 H2O) -56.577 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*898 Hydrogen fluoride HF (aq, 100000 H2O) -330.12 ± 0.16 kJ/mol 20.006343 ± 0.000070 7664-39-3*861 Ammonium hydroxide NH4OH (aq, 2.5 H2O) -364.92 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*804 Ethynol HCCOH (g, t-c triplet) 406.2 403.0 ± 3.1 kJ/mol 42.0367 ± 0.0016 32038-79-2*12 3-Methylene-1-cyclopropen-1-ylium [CH2C(CHC)]+ (g) 1398.8 1395.5 ± 1.7 kJ/mol 51.0661 ± 0.0032 117469-28-0*0 Dimethyl carbonate C(O)(OCH3)2 (g, cis-trans) -537.1 -557.7 ± 1.8 kJ/mol 90.0779 ± 0.0026 616-38-6*2 Isocyanic fluoride cation [FNC]+ (g) 1618.0 1618.6 ± 4.0 kJ/mol 45.01529 ± 0.00080 *16992-26-0*0 N-Methylenemethaniminium [CH2NCH2]+ (g) 904.4 893.4 ± 3.1 kJ/mol 42.0594 ± 0.0016 88333-01-1*0 2-Cyclopropen-1-ylidenemethylium [CHC(CHCH)]+ (g) 1346.5 1343.9 ± 1.8 kJ/mol 51.0661 ± 0.0032 112936-36-4*0 N-Methylenemethaniminium [CH2NCH2]+ (g, triplet) 1157.2 1147.3 ± 4.0 kJ/mol 42.0594 ± 0.0016 88333-01-1*1 Isocyanic fluoride anion [FNC]- (g) 73.9 75.6 ± 5.7 kJ/mol 45.01639 ± 0.00080 357426-78-9*0 Formylimidogen HC(O)N (g, triplet) 245.2 242.1 ± 4.6 kJ/mol 43.02478 ± 0.00086 42288-92-6*1 N-Methylidynemethanaminium [CH3NCH]+ (g) 881.1 870.3 ± 3.0 kJ/mol 42.0594 ± 0.0016 64709-60-0*0 1,3-Cyclobutadien-1-ylium [C(CHCHCH)]+ (g) 1388.4 1383.4 ± 1.8 kJ/mol 51.0661 ± 0.0032 81913-77-1*0 Hydrogen iodide HI (aq, 200 H2O) -56.192 ± 0.097 kJ/mol 127.912410 ± 0.000076 10034-85-2*830 Diazene HNNH (g, trans-cis equilib) 207.17 200.03 ± 0.40 kJ/mol 30.02936 ± 0.00020 3618-05-1*1 (Methylimino)methyl CH3NCH (g) 278.0 267.9 ± 1.1 kJ/mol 42.0599 ± 0.0016 117928-23-1*0 Cyclobutenide [CH2(CHCHCH)]- (g) 320.4 307.9 ± 3.2 kJ/mol 53.0830 ± 0.0032 60211-42-9*0 2-Propenylidene CHCHCH2 (g, triplet) 417.6 410.6 ± 1.5 kJ/mol 40.0639 ± 0.0024 19527-08-3*1 Ethynol HCCOH (g, t-t triplet) 409.2 406.1 ± 3.1 kJ/mol 42.0367 ± 0.0016 32038-79-2*13 (Methylimino)methyl CH3NCH (g, cis) 297.1 287.1 ± 2.0 kJ/mol 42.0599 ± 0.0016 117928-23-1*2 (Methylimino)methanide [CH3NCH]- (g) 223.0 212.2 ± 3.2 kJ/mol 42.0604 ± 0.0016 *64709-60-0*0 Phenylperoxy cation [C6H5OO]+ (g) 1019.1 1002.0 ± 3.1 kJ/mol 109.1022 ± 0.0049 956036-17-2*0 Phenylperoxy anion [C6H5OO]- (g) -38.8 -55.7 ± 3.3 kJ/mol 109.1032 ± 0.0049 *956036-17-2*0 (Methylimino)methanide [CH3NCH]- (g, cis) 236.6 225.7 ± 3.6 kJ/mol 42.0604 ± 0.0016 *64709-60-0*2 Hydrogen iodide HI (aq, 30 H2O) -55.51 ± 0.11 kJ/mol 127.912410 ± 0.000076 10034-85-2*820 Acetic acid CH3C(O)OH (aq, 12 H2O) -483.74 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*816 1-Aminoethenylium [CH2CNH2]+ (g) 900.0 889.2 ± 3.0 kJ/mol 42.0594 ± 0.0016 *139597-26-5*0 Hydrogen chloride HCl (aq, 100000 H2O) -166.948 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*861 Fulvene cation [CH2C(CHCHCHCH)]+ (g) 1043.7 1027.9 ± 2.7 kJ/mol 78.1113 ± 0.0048 34504-75-1*0 Fulvene anion [CH2C(CHCHCHCH)]- (g) 191.4 176.4 ± 4.0 kJ/mol 78.1124 ± 0.0048 34504-63-7*0 Ammonium hydroxide NH4OH (aq, 7000 H2O) -366.28 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*846 Formic acid cation [HC(O)OH]+ (g) 722.00 715.46 ± 0.24 kJ/mol 46.0248 ± 0.0010 50614-05-6*0 cis-1,3,5-Hexatriene CH2CHCHCHCHCH2 (g, cis) 190.7 170.6 ± 2.9 kJ/mol 80.1277 ± 0.0048 2612-46-6*0 Formic acid anion [HC(O)OH]- (g) -256.1 -262.3 ± 1.8 kJ/mol 46.0259 ± 0.0010 19066-82-1*0 Bromoform CHBr3 (l) 8.78 ± 0.71 kJ/mol 252.7306 ± 0.0031 75-25-2*590 Hydrogen iodide HI (aq, 4 H2O) -44.15 ± 0.30 kJ/mol 127.912410 ± 0.000076 10034-85-2*807 1-Aminoethenide [CH2CNH2]- (g) 216.0 205.2 ± 3.2 kJ/mol 42.0604 ± 0.0016 139597-26-5*0 Fulvenone cation [OCC(CHCHCHCH)]+ (g) 913.5 903.3 ± 1.9 kJ/mol 92.0948 ± 0.0048 884319-80-6*0 Trihydrogen HHH (g, TS) 254.5 250.7 ± 1.2 kJ/mol 3.02382 ± 0.00021 12184-91-7*200 Hydrogen peroxide HOOH (aq) -190.72 ± 0.25 kJ/mol 34.01468 ± 0.00062 7722-84-1*800 Dinitrogen anion [N2]- (g) 192.5 192.5 ± 1.7 kJ/mol 28.01403 ± 0.00014 12185-02-3*0 1,1-Ethenediol CH2C(OH)2 (g) -307.51 -320.05 ± 0.82 kJ/mol 60.0520 ± 0.0017 10375-04-9*0 Silicon atom tetracation [Si]+4 (g) 10401.10 10404.08 ± 0.56 kJ/mol 28.08331 ± 0.00030 22537-24-2*0 Silicon anion Si- (g) 316.28 319.26 ± 0.56 kJ/mol 28.08605 ± 0.00030 14337-02-1*0 Acetic acid CH3C(O)OH (aq, 15 H2O) -483.91 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*817 Methoxymethylene CH3OCH (g, singlet) 129.25 118.75 ± 0.78 kJ/mol 44.0526 ± 0.0017 19527-10-7*2 Disilicon anion [Si2]- (g) 375.1 379.0 ± 1.7 kJ/mol 56.17155 ± 0.00060 64236-73-3*0 Iodine monochloride ICl (cr,l) -36.511 -35.537 ± 0.063 kJ/mol 162.35717 ± 0.00090 7790-99-0*500 1,1-Ethenediol CH2C(OH)2 (g, syn-syn C2v) -302.3 -315.6 ± 1.9 kJ/mol 60.0520 ± 0.0017 10375-04-9*2 Hydrogen bromide HBr (aq, 100 H2O) -119.50 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*828 Chlorine atom Cl (g, 2P1/2) 130.176 131.783 ± 0.0011 kJ/mol 35.45270 ± 0.00090 22537-15-1*2 Hydrogen iodide HI (aq, 75 H2O) -55.962 ± 0.099 kJ/mol 127.912410 ± 0.000076 10034-85-2*825 Difluoromethane CH2F2 (l) -468.91 ± 0.37 kJ/mol 52.02339 ± 0.00081 75-10-5*590 1,1-Ethenediol CH2C(OH)2 (g, gauche-gauche C2) -296.0 -309.2 ± 1.9 kJ/mol 60.0520 ± 0.0017 10375-04-9*3 Hydrogen iodide HI (aq, 3000 H2O) -56.598 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*842 Ethynol HCCOH (g, c-t triplet) 455.3 452.0 ± 3.1 kJ/mol 42.0367 ± 0.0016 32038-79-2*14 1,3-Propanediyl CH2CH2CH2 (g, singlet TS) 337.7 323.0 ± 2.2 kJ/mol 42.0797 ± 0.0024 32458-33-6*2 Hydrogen chloride HCl (aq, 30 H2O) -164.501 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*820 Dibromomethane CH2Br2 (l) -31.42 ± 0.61 kJ/mol 173.8346 ± 0.0022 74-95-3*590 Silicon carbide anion [SiC]- (g) 508.8 513.4 ± 4.3 kJ/mol 40.09675 ± 0.00085 86017-99-4*0 Hydrogen bromide HBr (aq, 500 H2O) -119.97 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*833 Methane anion [CH4]- (g) 27.3 19.4 ± 5.1 kJ/mol 16.04301 ± 0.00085 27680-53-1*0 Silicon carbide SiC (cr,l) -70.6 -71.6 ± 1.5 kJ/mol 40.09620 ± 0.00085 409-21-2*500 Methane CH4 (aq, undissoc) -87.692 ± 0.062 kJ/mol 16.04246 ± 0.00085 74-82-8*1000 2-Aminoethenyl CHCHNH2 (g) 319.8 310.2 ± 1.3 kJ/mol 42.0599 ± 0.0016 176964-54-8*0 Glycolaldehyde HC(O)CH2OH (g) -304.28 -317.32 ± 0.89 kJ/mol 60.0520 ± 0.0017 141-46-8*0 Trifluorosilyl anion [SiF3]- (g) -1225.8 -1229.1 ± 3.4 kJ/mol 85.08126 ± 0.00030 54711-93-2*0 Trioxodinitrate anion [ONN(O)O]- (g) -104.3 -107.5 ± 1.9 kJ/mol 76.01223 ± 0.00091 194856-62-7*0 2-Aminoethenylium [CHCHNH2]+ (g, triplet) 1110.6 1099.9 ± 2.4 kJ/mol 42.0594 ± 0.0016 64724-21-6*1 Difluorosilylene anion [SiF2]- (g) -652.8 -653.1 ± 3.4 kJ/mol 66.08285 ± 0.00030 145089-80-1*0 Difluorosilylene SiF2 (g) -629.1 -630.0 ± 1.3 kJ/mol 66.08231 ± 0.00030 13966-66-0*0 Difluorosilylene SiF2 (g, triplet) -314.3 -314.9 ± 1.3 kJ/mol 66.08231 ± 0.00030 13966-66-0*1 Peroxychlorous acid HOOClO (g, perp ?) 101.5 95.4 ± 3.6 kJ/mol 84.4588 ± 0.0013 177778-92-6*3 Diazene anion [HNNH]- (g, trans-cis-iso equilib) 265.6 258.8 ± 2.0 kJ/mol 30.02991 ± 0.00020 100429-75-2*0 2-Aminoethenyl anion [CHCHNH2]- (g) 230.2 219.4 ± 2.6 kJ/mol 42.0604 ± 0.0016 *64724-21-6*0 Formate [HC(O)O]- (aq) -425.44 ± 0.45 kJ/mol 45.0180 ± 0.0010 71-47-6*800 Fluorosilylidyne SiF (g, quartet) 297.19 298.41 ± 0.62 kJ/mol 47.08390 ± 0.00030 11128-24-8*2 Ethynol HCCOH (g, c-c triplet) 464.0 460.7 ± 3.1 kJ/mol 42.0367 ± 0.0016 32038-79-2*15 Hydrogen fluoride HF (aq, 4000 H2O) -324.14 ± 0.13 kJ/mol 20.006343 ± 0.000070 7664-39-3*843 Hydroxyaminylium [HNOH]+ (g) 1019.5 1012.3 ± 2.5 kJ/mol 32.02147 ± 0.00034 66097-71-0*0 Formic acid HC(O)OH (aq, 0.25 H2O) -424.91 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*924 Ethylimidogen anion [CH3CH2N]- (g) 277.3 263.4 ± 3.6 kJ/mol 43.0684 ± 0.0016 82539-33-1*0 Formic acid HC(O)OH (aq, 0.5 H2O) -425.12 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*923 1-Propen-1-yl-3-ylidene CHCHCH (g) 656.8 653.4 ± 1.1 kJ/mol 39.0559 ± 0.0024 84654-90-0*0 [1.1.1]Propellane (CH2)3(CC) (g) 378.6 361.0 ± 1.5 kJ/mol 66.1011 ± 0.0040 35634-10-7*0 Formic acid HC(O)OH (aq, 1 H2O) -425.40 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*801 Silylene SiH2 (g) 271.60 269.94 ± 0.81 kJ/mol 30.10138 ± 0.00033 13825-90-6*0 Formic acid HC(O)OH (aq, 1.5 H2O) -425.50 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*802 Ethylimidogen cation [CH3CH2N]+ (g, quartet) 1394.6 1381.4 ± 3.6 kJ/mol 43.0673 ± 0.0016 *82539-33-1*1 5-Ethenyl-1,3-cyclopentadiene CH2CHCH(CHCHCHCH) (g) 237.2 216.3 ± 1.4 kJ/mol 92.1384 ± 0.0056 29647-85-6*0 Disilane cation [SiH3SiH3]+ (g) 1030.2 1017.4 ± 2.2 kJ/mol 62.21809 ± 0.00073 96301-43-8*0 Hydrogen fluoride HF (aq, 10000 H2O) -325.42 ± 0.16 kJ/mol 20.006343 ± 0.000070 7664-39-3*850 Nitrous acid anion [HONO]- (g) -105.84 -109.31 ± 0.78 kJ/mol 47.01403 ± 0.00061 256393-36-9*0 Tetrafluorohydrazine cation [NF2NF2]+ (g) 1129.2 1123.0 ± 2.5 kJ/mol 104.00654 ± 0.00014 37366-75-9*0 Acetic acid CH3C(O)OH (aq, 20 H2O) -484.09 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*818 Trihydrogen H(HH) (g, TS) 477.4 474.7 ± 2.3 kJ/mol 3.02382 ± 0.00021 12184-91-7*201 Formic acid HC(O)OH (aq, 2 H2O) -425.47 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*803 Formic acid HC(O)OH (aq, 2.5 H2O) -425.43 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*804 Hydrogen bromide HBr (aq, 555.1 H2O) -119.99 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*895 Disilene SiH2SiH2 (g) 288.8 280.2 ± 1.7 kJ/mol 60.20276 ± 0.00066 15435-77-5*0 5-Ethenyl-1,3-cyclopentadiene CH2CHCH(CHCHCHCH) (g, gauche) 242.1 220.2 ± 2.2 kJ/mol 92.1384 ± 0.0056 29647-85-6*2 Ammonium hydroxide NH4OH (aq, 20000 H2O) -366.18 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*852 1-Aziridinylium [N(CH2CH2)]+ (g, triplet) 1265.9 1254.2 ± 3.1 kJ/mol 42.0594 ± 0.0016 91127-35-4*1 Hydroxyethenylidene CCHOH (g) 302.1 300.7 ± 2.1 kJ/mol 42.0367 ± 0.0016 70277-80-4*0 Silylsilylene SiH3SiH (g) 317.3 309.5 ± 1.9 kJ/mol 60.20276 ± 0.00066 50420-90-1*0 Cyanomethylium [CH2CN]+ (g) 1256.23 1253.59 ± 0.61 kJ/mol 40.0435 ± 0.0016 34430-18-7*0 Carbon C (diamond) 2.389 1.861 ± 0.043 kJ/mol 12.01070 ± 0.00080 7440-44-0*501 mu-Oxodioxodinitrogen [ONONO]+ (g, t, t) 984.0 981.0 ± 3.2 kJ/mol 76.01113 ± 0.00091 87950-63-8*1 Formic acid HC(O)OH (aq, 3 H2O) -425.39 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*805 Hydroxyethenylidene CCHOH (g, triplet) 418.2 414.8 ± 2.4 kJ/mol 42.0367 ± 0.0016 70277-80-4*1 1-Aziridinide [N(CH2CH2)]- (g) 244.2 231.8 ± 3.3 kJ/mol 42.0604 ± 0.0016 1358579-49-3*0 Formic acid HC(O)OH (aq, 4 H2O) -425.32 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*807 Hydrogen peroxide HOOH (g, ortho) -129.398 -135.404 ± 0.058 kJ/mol 34.01468 ± 0.00062 7722-84-1*1 Di-mu-hydrodihydrodisilicon HSi(HSiHH) (g) 374.8 364.5 ± 2.3 kJ/mol 60.20276 ± 0.00066 129970-82-7*0 Di-mu-hydrodihydrodisilicon HSi(HSiHH) (g, trans) 374.8 364.4 ± 2.3 kJ/mol 60.20276 ± 0.00066 129970-82-7*1 Di-mu-hydrodihydrodisilicon HSi(HSiHH) (g, trans-triplet) 544.3 536.2 ± 3.6 kJ/mol 60.20276 ± 0.00066 129970-82-7*11 Di-mu-hydrodihydrodisilicon cation [HSi(HSiHH)]+ (g) 1180.3 1172.7 ± 3.2 kJ/mol 60.20221 ± 0.00066 *129970-82-7*0 Di-mu-hydrodihydrodisilicon anion [HSi(HSiHH)]- (g) 288.5 280.4 ± 3.3 kJ/mol 60.20331 ± 0.00066 *129970-83-8*0 Formic acid HC(O)OH (aq, 5 H2O) -425.27 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*809 Ethynylaminylium [HCCNH]+ (g) 1277.8 1277.4 ± 2.6 kJ/mol 40.0435 ± 0.0016 103835-08-1*0 Hydrogen bromide HBr (aq, 100000 H2O) -120.43 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*861 Formic acid HC(O)OH (aq, 6 H2O) -425.22 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*811 Trihydrogen H(HH) (g, Ry) 745.878 743.199 ± 0.062 kJ/mol 3.02382 ± 0.00021 12184-91-7*0 Hydrogen chloride HCl (aq, 500 H2O) -166.404 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*833 Methyl hydrocarbonate C(O)(OH)OCH3 (g, cis-trans) -571.8 -587.2 ± 1.9 kJ/mol 76.0514 ± 0.0019 7456-87-3*2 Hydrogen chloride HCl (aq, 15 H2O) -162.856 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*817 Hydrogen bromide HBr (aq, 25 H2O) -118.35 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*819 Formic acid HC(O)OH (aq, 7 H2O) -425.19 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*812 Formic acid HC(O)OH (aq, 8 H2O) -425.17 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*813 Formic acid HC(O)OH (aq, 9 H2O) -425.16 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*814 Hydrogen chloride HCl (aq, 111 H2O) -165.820 ± 0.024 kJ/mol 36.46064 ± 0.00090 7647-01-0*892 Formic acid HC(O)OH (aq, 10 H2O) -425.16 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*815 Methoxymethylene CH3OCH (g) 129.25 118.75 ± 0.78 kJ/mol 44.0526 ± 0.0017 19527-10-7*0 2-Aziridinyl NH(CHCH2) (g) 361.0 349.5 ± 1.7 kJ/mol 42.0599 ± 0.0016 *23838-09-7*0 2-Aziridinylium [NH(CHCH2)]+ (g) 1010.9 998.9 ± 3.3 kJ/mol 42.0594 ± 0.0016 *91127-35-4*0 Formic acid HC(O)OH (aq, 12 H2O) -425.16 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*816 Methyl hydrocarbonate C(O)(OH)OCH3 (g, trans-cis) -562.8 -578.3 ± 1.9 kJ/mol 76.0514 ± 0.0019 7456-87-3*3 Formic acid HC(O)OH (aq, 15 H2O) -425.16 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*817 2-Aziridinylium [NH(CHCH2)]+ (g, triplet) 1305.0 1293.3 ± 4.1 kJ/mol 42.0594 ± 0.0016 *91127-35-4*1 Perchloric acid cation [HOCl(O)(O)O]+ (g) 1190.2 1180.6 ± 3.3 kJ/mol 100.4577 ± 0.0015 91712-47-9*0 2-(Cyclopenta-2,4-dien-1-ylidene)ethan-1-ide [CH2CHC(CHCHCHCH)]- (g) 132.6 114.5 ± 3.4 kJ/mol 91.1310 ± 0.0056 405519-46-2*0 Methyl hydrocarbonate C(O)(OH)OCH3 (g, trans-trans) -532.5 -547.6 ± 2.0 kJ/mol 76.0514 ± 0.0019 7456-87-3*4 Hydroxyethenylidene CCHOH (g, anti-triplet) 438.5 434.8 ± 3.0 kJ/mol 42.0367 ± 0.0016 70277-80-4*12 Hydrogen iodide HI (aq, 4000 H2O) -56.623 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*843 Hydrogen bromide HBr (aq, 40 H2O) -118.90 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*821 Nitrato [ON(O)O]+ (g) 1290.59 1285.88 ± 0.86 kJ/mol 62.00439 ± 0.00090 133057-96-2*0 Hydrogen chloride HCl (aq, 400 H2O) -166.337 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*832 Hydroxysilyl anion [SiH2OH]- (g) -219.2 -227.0 ± 2.1 kJ/mol 47.10927 ± 0.00047 78450-47-2*0 Hydroxysilyl anion [SiH2OH]- (g, anti) -218.9 -226.8 ± 2.7 kJ/mol 47.10927 ± 0.00047 78450-47-2*2 2-Aziridinylium [NH(CHCH2)]+ (g, syn-triplet) 1335.0 1324.0 ± 4.8 kJ/mol 42.0594 ± 0.0016 *91127-35-4*11 2-Aziridinide [NH(CHCH2)]- (g) 316.2 304.1 ± 3.4 kJ/mol 42.0604 ± 0.0016 111127-93-6*0 Ammonium hydroxide NH4OH (aq, 12 H2O) -366.07 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*816 2-Aziridinide [NH(CHCH2)]- (g, syn) 330.2 318.1 ± 4.0 kJ/mol 42.0604 ± 0.0016 111127-93-6*1 Benzvalene cation [((CHCH)(CH(CHCH)CH))]+ (g) 1200.3 1184.9 ± 2.7 kJ/mol 78.1113 ± 0.0048 81050-63-7*0 Diazanide [NH2NH]- (g) 249.3 239.3 ± 3.1 kJ/mol 31.03785 ± 0.00025 25415-88-7*0 Vinylcyclopentadienylium [CH2CHC(CHCHCHCH)]+ (g) 1076.9 1059.5 ± 3.7 kJ/mol 91.1299 ± 0.0056 146893-89-2*0 Methanediimine cation [HNCNH]+ (g) 1137.8 1135.7 ± 2.2 kJ/mol 42.03951 ± 0.00082 1189338-16-6*0 Hydrogen bromide HBr (aq, 15 H2O) -117.38 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*817 Methanediimine cation [HNCNH]+ (g, trans) 1139.1 1136.2 ± 3.2 kJ/mol 42.03951 ± 0.00082 1189338-16-6*1 Formic acid HC(O)OH (aq, 20 H2O) -425.16 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*818 Vinylcyclopentadienylium [CH2CHC(CHCHCHCH)]+ (g, triplet) 1099.4 1081.5 ± 4.5 kJ/mol 91.1299 ± 0.0056 146893-89-2*1 Isocyanogen chloride cation [ClNC]+ (g) 1481.0 1482.2 ± 3.9 kJ/mol 61.4696 ± 0.0012 956475-91-5*0 Ammonium hydroxide NH4OH (aq, 15 H2O) -366.13 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*817 1-Propen-1-yl-3-ylidene CHCHCH (g, c-t quartet) 656.8 653.2 ± 2.0 kJ/mol 39.0559 ± 0.0024 84654-90-0*12 1,2-Propadien-1-yl-3-ylidene anion [CCC]- (g, lin) 621.7 629.1 ± 1.3 kJ/mol 36.0326 ± 0.0024 109292-47-9*1 Butadienylacetylene CH2CHCHCHCCH (g) 358.9 346.5 ± 1.9 kJ/mol 78.1118 ± 0.0048 10420-90-3*0 Tetraoxidanyl HOOOO (g, trans) 76.7 69.5 ± 6.1 kJ/mol 65.0055 ± 0.0012 69696-93-1*1 (3Z)-1,3-Hexadien-5-yne CH2CHCHCHCCH (g, cis) 358.9 346.3 ± 2.5 kJ/mol 78.1118 ± 0.0048 5222-76-4*0 Divinylacetylene CH2CHCCCHCH2 (g) 361.9 350.8 ± 1.9 kJ/mol 78.1118 ± 0.0048 821-08-9*0 Tetraoxidanyl HOOOO (g) 2.1 0.4 ± 2.9 kJ/mol 65.0055 ± 0.0012 69696-93-1*0 Divinylacetylene CH2CHCCCHCH2 (g, trans) 362.5 351.4 ± 2.6 kJ/mol 78.1118 ± 0.0048 821-08-9*1 Biallenyl CH2CCHCHCCH2 (g) 410.7 399.6 ± 1.5 kJ/mol 78.1118 ± 0.0048 29776-96-3*0 Hydrogen fluoride HF (aq, 1000 H2O) -322.71 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*839 Biallenyl CH2CCHCHCCH2 (g, cis) 419.6 408.2 ± 2.2 kJ/mol 78.1118 ± 0.0048 29776-96-3*2 Propargylallene CH2CCHCH2CCH (g) 431.5 420.1 ± 1.4 kJ/mol 78.1118 ± 0.0048 33142-15-3*0 Formic acid HC(O)OH (aq, 25 H2O) -425.17 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*819 Propargylallene CH2CCHCH2CCH (g, cis) 432.4 420.8 ± 2.2 kJ/mol 78.1118 ± 0.0048 33142-15-3*2 Formic acid HC(O)OH (aq, 30 H2O) -425.17 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*820 Formic acid HC(O)OH (aq, 40 H2O) -425.19 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*821 3-Methylene-1-penten-4-yne CH2CHC(CH2)CCH (g) 362.7 350.3 ± 2.2 kJ/mol 78.1118 ± 0.0048 6929-96-0*0 3-Methylene-1-penten-4-yne CH2CHC(CH2)CCH (g, gauche) 374.8 362.5 ± 2.8 kJ/mol 78.1118 ± 0.0048 6929-96-0*3 1,2,3,5-Hexatetraene CH2CCCHCHCH2 (g) 391.8 380.4 ± 1.6 kJ/mol 78.1118 ± 0.0048 60239-33-0*0 Methyl hydrocarbonate C(O)(OH)OCH3 (cr,l) -629.1 ± 1.4 kJ/mol 76.0514 ± 0.0019 7456-87-3*500 1,2,3,5-Hexatetraene CH2CCCHCHCH2 (g, cis) 400.6 389.0 ± 2.3 kJ/mol 78.1118 ± 0.0048 60239-33-0*2 (Dimethylamino)methyl anion [(CH3)2NCH2]- (g) 190.9 166.7 ± 3.3 kJ/mol 58.1029 ± 0.0025 125231-49-4*0 Peroxyhypochlorous acid cation [HOOCl]+ (g) 1030.4 1024.6 ± 2.5 kJ/mol 68.4589 ± 0.0011 *67952-07-2*0 Hydrogen isocyanide anion [HNC]- (g) 191.63 191.81 ± 0.32 kJ/mol 27.02593 ± 0.00081 96913-22-3*0 Trichlorine cation [Cl3]+ (g) 1056.6 1055.5 ± 1.4 kJ/mol 106.3576 ± 0.0027 33088-85-6*0 Vinyl alcohol cation [CH2CHOH]+ (g) 778.7 767.7 ± 1.3 kJ/mol 44.0520 ± 0.0017 57239-63-1*0 Difluorodiazene FNNF (g) 78.5 73.4 ± 2.1 kJ/mol 66.01029 ± 0.00014 10578-16-2*0 Methoxyethene CH2CHOCH3 (g) -89.3 -106.6 ± 1.1 kJ/mol 58.0791 ± 0.0025 107-25-5*0 Hydrogen bromide HBr (aq, 700 H2O) -120.04 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*835 Hydrogen iodide HI (aq, 3 H2O) -36.91 ± 0.56 kJ/mol 127.912410 ± 0.000076 10034-85-2*805 Hydrogen chloride HCl (aq, 900 H2O) -166.542 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*838 Formic acid HC(O)OH (aq, 50 H2O) -425.21 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*822 Acetic acid CH3C(O)OH (aq, undissoc) -484.78 ± 0.27 kJ/mol 60.0520 ± 0.0017 64-19-7*1000 Diazene anion [HNNH]- (g, trans-cis equilib) 265.6 258.8 ± 2.0 kJ/mol 30.02991 ± 0.00020 100429-75-2*1 1-Methylallyl CH3CHCHCH2 (g) 152.70 136.23 ± 0.79 kJ/mol 55.0984 ± 0.0032 15819-46-2*0 Formic acid HC(O)OH (aq, 55.51 H2O) -425.22 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*891 Dioxodiazoxane ONONO (g) 93.0 88.1 ± 1.3 kJ/mol 76.01168 ± 0.00091 122413-35-8*0 1-Methyl-1-propenyl CH3CCHCH3 (g) 240.12 224.74 ± 0.66 kJ/mol 55.0984 ± 0.0032 71790-71-1*0 Dicarbon monoxide CCO (g) 377.13 381.17 ± 0.83 kJ/mol 40.0208 ± 0.0016 12071-23-7*0 1-Methyl-1-propenyl CH3CCHCH3 (g, cis) 243.5 227.1 ± 1.9 kJ/mol 55.0984 ± 0.0032 71790-71-1*2 Hydrogen iodide HI (aq, 7000 H2O) -56.665 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*846 Cyanogen NCCN (cr,l) 273.95 289.20 ± 0.41 kJ/mol 52.0349 ± 0.0016 460-19-5*500 1-Butenyl CH3CH2CHCH (g) 263.48 246.42 ± 0.68 kJ/mol 55.0984 ± 0.0032 2669-61-6*0 Diatomic bromine cation [Br2]+ (g) 1060.34 1045.39 ± 0.23 kJ/mol 159.8075 ± 0.0020 12595-71-0*0 1-Butenyl CH3CH2CHCH (g, gauche) 263.9 246.7 ± 1.9 kJ/mol 55.0984 ± 0.0032 2669-61-6*3 Hydrogen fluoride HF (aq, 300 H2O) -322.16 ± 0.10 kJ/mol 20.006343 ± 0.000070 7664-39-3*831 1-Ethynyl-2-propyn-1-ylium-1-yl [HCCCCCH]+ (g) 1537.2 1540.9 ± 2.6 kJ/mol 62.0688 ± 0.0040 217822-76-9*0 1-Ethynyl-2-propyn-1-ylidene anion [HCCCCCH]- (g) 584.3 589.3 ± 3.5 kJ/mol 62.0699 ± 0.0040 217822-70-3*0 1-Ethynyl-2-propyn-1-ylidene HCCCCCH (g) 727.1 734.1 ± 1.7 kJ/mol 62.0694 ± 0.0040 882068-94-2*0 1-Ethynyl-2-propyn-1-ylidene HCCCCCH (g, singlet) 787.5 793.0 ± 2.1 kJ/mol 62.0694 ± 0.0040 882068-94-2*2 Hydrogen iodide HI (aq, 7 H2O) -51.301 ± 0.099 kJ/mol 127.912410 ± 0.000076 10034-85-2*812 Isocyanoamidogen HNNC (g, t-quartet) 837.9 835.3 ± 2.1 kJ/mol 41.03212 ± 0.00082 947408-73-3*21 Water H2O (cr, l, eq.press.) -286.275 -285.802 ± 0.022 kJ/mol 18.01528 ± 0.00033 7732-18-5*499 Isocyanogen anion [CNCN]- (g) 386.6 388.7 ± 3.3 kJ/mol 52.0354 ± 0.0016 *83951-85-3*0 1,2-Pentadien-4-ynylidene HCCCHCC (g) 791.3 794.1 ± 2.4 kJ/mol 62.0694 ± 0.0040 195524-67-5*0 2-Cyclopropen-1-ylideneethenylidene CCC(CHCH) (g) 807.2 808.8 ± 3.4 kJ/mol 62.0694 ± 0.0040 195524-69-7*0 1-Propen-1-yl-3-ylidene CHCHCH (g, t-t quartet) 665.8 662.3 ± 2.0 kJ/mol 39.0559 ± 0.0024 84654-90-0*13 Hydrazoic acid anion [HNNN]- (g) 309.1 303.2 ± 2.3 kJ/mol 43.02871 ± 0.00022 203264-98-6*0 Hydrogen iodide HI (aq, 10000 H2O) -56.690 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*850 Formic acid HC(O)OH (aq, 75 H2O) -425.24 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*825 Hydroperoxyimidogen HOON (g, cis) 111.9 109.0 ± 2.8 kJ/mol 47.01348 ± 0.00061 877456-58-1*2 Oxiranylidene CH2(CO) (g) 213.5 209.3 ± 1.4 kJ/mol 42.0367 ± 0.0016 50983-85-2*0 Hydrodioxonitrogen cation [HN(O)O]+ (g) 1130.1 1123.5 ± 2.9 kJ/mol 47.01293 ± 0.00061 252986-76-8*0 Hydrazoic acid HNNN (cr,l) 261.57 ± 0.64 kJ/mol 43.02816 ± 0.00022 7782-79-8*500 2,4-Pentadiynylium [HCCCCCH2]+ (g) 1362.6 1362.6 ± 2.6 kJ/mol 63.0768 ± 0.0040 103928-86-5*0 Pentatetraen-1-ide [HCCCCCH2]- (g) 433.5 434.0 ± 3.4 kJ/mol 63.0779 ± 0.0040 849427-36-7*0 1-Ethynyl-2-propynylium [CHCCHCCH]+ (g) 1380.0 1378.7 ± 2.6 kJ/mol 63.0768 ± 0.0040 79530-50-0*0 COC vdW (CO)(C) (g) 589.7 598.5 ± 1.5 kJ/mol 40.0208 ± 0.0016 *12071-24-8*0 Penta-1,4-diyn-3-ide [CHCCHCCH]- (g) 443.9 443.2 ± 3.2 kJ/mol 63.0779 ± 0.0040 553662-77-4*0 Penta-1,4-diyn-3-ide [CHCCHCCH]- (g, anti) 443.9 443.2 ± 3.6 kJ/mol 63.0779 ± 0.0040 553662-77-4*2 Hydrogen fluoride HF (aq, 800 H2O) -322.57 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*837 Ethylamine CH3CH2NH2 (cr,l) -76.79 ± 0.65 kJ/mol 45.0837 ± 0.0017 75-04-7*500 Hydrogen iodide HI (aq, 9 H2O) -52.89 ± 0.16 kJ/mol 127.912410 ± 0.000076 10034-85-2*814 Hydrobromate ion [HBr]- (g) -5.5 -12.0 ± 4.3 kJ/mol 80.9125 ± 0.0010 85532-97-4*0 Iodoniumyl [HI]+ (g) 1030.73 1028.56 ± 0.11 kJ/mol 127.911861 ± 0.000076 12298-17-8*0 Hydrogen fluoride HF (aq, 400 H2O) -322.26 ± 0.10 kJ/mol 20.006343 ± 0.000070 7664-39-3*832 Hydrogen cyanide anion [HCN]- (g) 129.536 129.058 ± 0.087 kJ/mol 27.02593 ± 0.00081 12334-27-9*0 Diisocyanogen anion [CNNC]- (g) 456.8 462.5 ± 3.6 kJ/mol 52.0354 ± 0.0016 *78800-22-3*0 1-Aminoethyl anion [CH3CHNH2]- (g) 174.6 157.0 ± 3.2 kJ/mol 44.0763 ± 0.0017 59263-55-7*0 1,2-Difluoroethene CHFCHF (g) -302.96 -309.05 ± 0.83 kJ/mol 64.0341 ± 0.0016 1691-13-0*0 Formic acid HC(O)OH (aq, 111 H2O) -425.27 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*892 Ethylaminylium [CH3CH2NH]+ (g, triplet) 1092.4 1077.3 ± 2.4 kJ/mol 44.0752 ± 0.0017 54387-08-5*1 Ethylaminylium [CH3CH2NH]+ (g, anti-triplet) 1094.9 1079.2 ± 2.9 kJ/mol 44.0752 ± 0.0017 54387-08-5*12 Hydrogen iodide HI (aq, 20000 H2O) -56.728 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*852 Diisocyanogen cation [CNNC]+ (g) 1825.3 1828.5 ± 3.2 kJ/mol 52.0343 ± 0.0016 *78800-21-2*0 Ammonium hydroxide NH4OH (aq, 25 H2O) -366.24 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*819 Propylidyne CH3CH2C (g) 492.7 483.0 ± 1.2 kJ/mol 41.0718 ± 0.0024 85056-54-8*0 N-Methylethanamine CH3CH2NHCH3 (cr,l) -74.9 ± 2.3 kJ/mol 59.1103 ± 0.0025 624-78-2*500 Nitrosyl nitrite anion [ONONO]- (g) -103.1 -106.2 ± 2.8 kJ/mol 76.01223 ± 0.00091 *122413-35-8*0 Formic acid HC(O)OH (aq, 200 H2O) -425.30 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*830 Formic acid HC(O)OH (aq, 300 H2O) -425.30 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*831 2-Methyl-2-propanamine (CH3)3CNH2 (l) -150.59 ± 0.53 kJ/mol 73.1369 ± 0.0033 75-64-9*590 Diazirinyl HC(NN) (g) 491.09 487.70 ± 0.96 kJ/mol 41.03212 ± 0.00082 69967-71-1*0 Formic acid HC(O)OH (aq, 400 H2O) -425.31 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*832 Hydrogen fluoride HF (aq, 200 H2O) -322.08 ± 0.10 kJ/mol 20.006343 ± 0.000070 7664-39-3*830 Naphtalene cation [C6H4(C4H4)]+ (g) 956.93 933.86 ± 0.55 kJ/mol 128.1700 ± 0.0080 34512-27-1*0 Naphtalene anion [C6H4(C4H4)]- (g) 187.6 164.7 ± 3.0 kJ/mol 128.1711 ± 0.0080 34509-91-6*0 Diazoethenylidene cation [NNCC]+ (g) 1771.1 1773.1 ± 3.5 kJ/mol 52.0343 ± 0.0016 *130760-10-0*0 Hydrogen fluoride HF (aq, 2000 H2O) -323.39 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*841 3-Diaziridinylidene C(NHNH) (g) 521.9 515.0 ± 1.5 kJ/mol 42.04006 ± 0.00082 85513-79-7*0 Diazoethenylidene anion [NNCC]- (g) 529.6 532.2 ± 3.5 kJ/mol 52.0354 ± 0.0016 *130760-11-1*0 Difluorovinylidene anion [CCF2]- (g) -88.2 -87.1 ± 2.3 kJ/mol 62.0188 ± 0.0016 107693-92-5*0 Hydroxymethylene cation [HCOH]+ (g) 971.9 968.3 ± 1.4 kJ/mol 30.02543 ± 0.00087 135395-06-1*0 Dibromovinylidene CCBr2 (g) 524.1 513.0 ± 4.0 kJ/mol 183.8294 ± 0.0026 261771-36-2*0 Propane CH3CH2CH3 (cr,l) -110.18 -121.16 ± 0.66 kJ/mol 44.0956 ± 0.0025 74-98-6*500 Formic acid HC(O)OH (aq, 500 H2O) -425.31 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*833 3H-diazirin-3-ylidene-methylene CC(NN) (g) 837.3 839.9 ± 2.3 kJ/mol 52.0349 ± 0.0016 204253-88-3*0 Formic acid HC(O)OH (aq, 555.1 H2O) -425.31 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*895 Formic acid HC(O)OH (aq, 600 H2O) -425.32 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*834 Formic acid HC(O)OH (aq, 700 H2O) -425.32 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*835 Fluorovinylidene CCHF (g) 298.9 300.1 ± 3.1 kJ/mol 44.0277 ± 0.0016 70302-00-0*0 Isocyanomethane CH3NC (cr,l) 146.4 ± 2.2 kJ/mol 41.0520 ± 0.0016 593-75-9*500 Acetic acid CH3C(O)OH (aq, 0.5 H2O) -483.00 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*923 Diazenide [NNH]- (g) 175.7 176.7 ± 1.6 kJ/mol 29.02197 ± 0.00016 71004-29-0*0 Fluoroimidogen NF (g) 232.64 232.64 ± 0.80 kJ/mol 33.005143 ± 0.000070 13967-06-1*0 Hydrogen iodide HI (aq, 15 H2O) -54.586 ± 0.092 kJ/mol 127.912410 ± 0.000076 10034-85-2*817 Formic acid HC(O)OH (aq, 800 H2O) -425.32 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*837 Nitrogen atom N (g, doublet) 700.558 702.461 ± 0.022 kJ/mol 14.006740 ± 0.000070 17778-88-0*2 Benzophenone C6H5C(O)C6H5 (l) -24.8 ± 1.5 kJ/mol 182.2179 ± 0.0104 119-61-9*590 3-Diaziridinylidene C(NHNH) (g, syn) 537.0 530.3 ± 2.0 kJ/mol 42.04006 ± 0.00082 85513-79-7*2 Bromovinylidene CCHBr (g) 471.9 465.9 ± 3.8 kJ/mol 104.9333 ± 0.0019 161957-27-3*0 Butadiynylium [CCCCH]+ (g) 1781.3 1787.8 ± 3.2 kJ/mol 49.0502 ± 0.0032 76108-67-3*0 Diiodine cation [I2]+ (g) 963.523 960.408 ± 0.018 kJ/mol 253.808391 ± 0.000060 28712-14-3*0 Ammonium hydroxide NH4OH (aq, 30 H2O) -366.26 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*820 Formic acid HC(O)OH (aq, 900 H2O) -425.32 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*838 Formic acid HC(O)OH (aq, 1000 H2O) -425.32 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*839 Dinitrogen tetraoxide O2NNO2 (cr,l) -37.86 -27.01 ± 0.19 kJ/mol 92.0111 ± 0.0012 10544-72-6*500 Oxiranylium [CH2(CHO)]+ (g) 901.3 893.3 ± 1.4 kJ/mol 43.0441 ± 0.0016 57789-76-1*0 Helium He (g, singlet) -0.000 -0.000 ± 0.000 kJ/mol 4.0026020 ± 0.0000020 7440-59-7*2 3-Diaziridinylidene cation [C(NHNH)]+ (g) 1479.7 1473.7 ± 2.4 kJ/mol 42.03951 ± 0.00082 *85513-79-7*0 Hydrogen fluoride HF (aq, 18.5 H2O) -321.82 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*887 Helium dication [He]+2 (g) 7622.839 7622.839 ± 0.000 kJ/mol 4.0015048 ± 0.0000020 12587-46-1*0 3-Diaziridinylidene cation [C(NHNH)]+ (g, syn) 1497.3 1491.8 ± 3.1 kJ/mol 42.03951 ± 0.00082 *85513-79-7*2 Difluorophosgene anion [CF2O]- (g) -602.3 -604.2 ± 3.3 kJ/mol 66.00745 ± 0.00085 474815-26-4*0 Oxiranyl anion [CH2(CHO)]- (g) 121.2 113.3 ± 1.5 kJ/mol 43.0452 ± 0.0016 72722-59-9*0 Hydrogen chloride HCl (aq, 555.1 H2O) -166.431 ± 0.024 kJ/mol 36.46064 ± 0.00090 7647-01-0*895 Acetic acid CH3C(O)OH (aq, 25 H2O) -484.21 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*819 Dihelium He2 (g, singlet) 1761.349 1757.613 ± 0.018 kJ/mol 8.0052040 ± 0.0000040 12184-98-4*2 Hydroxymethylene anion [HCOH]- (g) 147.2 144.2 ± 1.6 kJ/mol 30.02653 ± 0.00087 207914-87-2*0 Hydrohelate [HeH]- (g) 143.256 139.027 ± 0.0021 kJ/mol 5.011091 ± 0.000070 12325-01-8*0 Fluoro(fluorooxy)methylene FCOF (g) -134.8 -136.0 ± 1.3 kJ/mol 66.00691 ± 0.00085 479587-30-9*0 Hydrogen bromide HBr (aq, 800 H2O) -120.06 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*837 Acetic acid CH3C(O)OH (aq, 30 H2O) -484.30 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*820 Peroxyhypochlorous acid anion [HOOCl]- (g, quartet) -32.2 -33.9 ± 2.6 kJ/mol 68.4600 ± 0.0011 *67952-08-3*0 Hydrogen iodide HI (aq, 8 H2O) -52.22 ± 0.12 kJ/mol 127.912410 ± 0.000076 10034-85-2*813 Hydrogen iodide HI (aq, 10 H2O) -53.37 ± 0.17 kJ/mol 127.912410 ± 0.000076 10034-85-2*815 Hydrogen chloride HCl (aq, 12 H2O) -162.011 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*816 Iminomethide [HCNH]- (g) 237.4 233.6 ± 1.8 kJ/mol 28.03387 ± 0.00082 90623-30-6*0 Carbon dianion [C]-2 (g) 1027.5 1033.0 ± 4.9 kJ/mol 12.01180 ± 0.00080 50802-47-6*0 Phosgene cation [CCl2O]+ (g) 897.0 896.0 ± 1.7 kJ/mol 98.9150 ± 0.0020 73249-38-4*0 Phosgene CCl2O (cr, l, I+liquid) -242.78 ± 0.24 kJ/mol 98.9155 ± 0.0020 75-44-5*501 Phosgene CCl2O (cr, l, II+liquid) -255.48 -242.78 ± 0.24 kJ/mol 98.9155 ± 0.0020 75-44-5*502 Fluorine atom nonacation [F]+9 (g) 262121.1 262122.9 ± 1.8 kJ/mol 18.99346598 ± 0.00000050 35424-07-8*0 Neon decacation [Ne]+10 (g) 338828.3 338828.3 ± 1.4 kJ/mol 20.17421 ± 0.00060 32218-07-8*0 Neon hydride NeH (g) 215.989 211.755 ± 0.024 kJ/mol 21.18764 ± 0.00060 17438-52-7*0 Chloro(chlorooxy)methylene ClCOCl (g) 73.5 73.9 ± 3.6 kJ/mol 98.9155 ± 0.0020 479587-31-0*0 Hydroneonate [NeH]- (g) 143.096 142.084 ± 0.035 kJ/mol 21.18819 ± 0.00060 75514-98-6*0 Chloro(chlorooxy)methylene ClCOCl (g, trans) 98. 105. ± 15. kJ/mol 98.9155 ± 0.0020 479587-31-0*1 Hydrogen fluoride HF (aq, 35 H2O) -321.91 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*904 Formic acid HC(O)OH (aq, 2000 H2O) -425.33 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*841 Acetic acid CH3C(O)OH (aq, 40 H2O) -484.42 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*821 Krypton dication [Kr]+2 (g) 3701.124 3701.124 ± 0.013 kJ/mol 83.7989 ± 0.1000 18469-91-5*0 Formic acid HC(O)OH (aq, 5000 H2O) -425.34 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*844 Xenon dication [Xe]+2 (g) 3194.14 3194.14 ± 0.36 kJ/mol 131.2889 ± 0.0200 14066-95-6*0 Formic acid HC(O)OH (aq, 10000 H2O) -425.34 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*850 Acetic acid CH3C(O)OH (aq, 1 H2O) -482.90 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*801 Tetroxidane HOOOOH (g, C2 I) -31.30 -41.80 ± 0.64 kJ/mol 66.0135 ± 0.0012 29683-94-1*22 Hydrogen iodide HI (aq, 300 H2O) -56.272 ± 0.092 kJ/mol 127.912410 ± 0.000076 10034-85-2*831 Acetic acid CH3C(O)OH (aq, 50 H2O) -484.49 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*822 Chlorohydroxymethylene ClCOH (g, cis) 14.4 11.6 ± 3.2 kJ/mol 64.4707 ± 0.0012 147723-60-2*2 Chlorohydroxymethylene ClCOH (g) 14.0 11.3 ± 2.5 kJ/mol 64.4707 ± 0.0012 147723-60-2*0 Cycloprop-2-yliumyl [CH2(CHCH)]+ (g) 1225.56 1218.41 ± 0.58 kJ/mol 40.0633 ± 0.0024 65812-78-4*0 Sulfur atom hexacation [S]+6 (g) 26947.2 26949.0 ± 3.4 kJ/mol 32.0627 ± 0.0060 22537-26-4*0 Chlorine pentafluoride cation [FCl(F)(F)(F)F]+ (g) 1005.9 996.9 ± 3.2 kJ/mol 130.44417 ± 0.00090 478167-78-1*0 Sulfur atom dianion [S]-2 (g) 454.0 455.8 ± 3.2 kJ/mol 32.0671 ± 0.0060 18496-25-8*0 Hydrogen bromide HBr (aq, 12 H2O) -116.68 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*816 Acetic acid CH3C(O)OH (aq, 1.5 H2O) -482.84 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*802 Disulfur anion [S2]- (g) -34.06 -33.12 ± 0.52 kJ/mol 64.1325 ± 0.0120 12185-15-8*0 (Chlorooxy)methylene HCOCl (g, trans) 155.5 155.3 ± 3.7 kJ/mol 64.4707 ± 0.0012 331419-80-8*1 Ozone OOO (aq, undissoc) 118.19 ± 0.50 kJ/mol 47.99820 ± 0.00090 10028-15-6*1000 Sulfonyl cation [OSO]+ (g) 897.01 894.74 ± 0.13 kJ/mol 64.0643 ± 0.0060 12439-77-9*0 Sulfur dioxide OSO (cr,l) -331.5 -320.1 ± 1.9 kJ/mol 64.0648 ± 0.0060 7446-09-5*500 Formic acid HC(O)OH (aq, 20000 H2O) -425.35 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*852 (Chlorooxy)methylene HCOCl (g) 119.3 117.9 ± 2.7 kJ/mol 64.4707 ± 0.0012 331419-80-8*0 Ammonium hydroxide NH4OH (aq, 40 H2O) -366.31 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*821 1-Methoxyethenol CH2C(OH)OCH3 (g) -284.2 -302.7 ± 1.1 kJ/mol 74.0785 ± 0.0025 4453-91-2*0 Oxosulfate [SO]- (g) -102.66 -101.89 ± 0.50 kJ/mol 48.0659 ± 0.0060 12269-52-2*0 Formic acid HC(O)OH (aq, 50000 H2O) -425.36 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*855 Sulfur trioxide cation [OS(O)O]+ (g) 847.65 844.74 ± 0.68 kJ/mol 80.0637 ± 0.0061 12710-95-1*0 Chloroformyl anion [ClCO]- (g) -356.5 -352.9 ± 3.3 kJ/mol 63.4633 ± 0.0012 41976-93-6*0 Sulfite [OS(O)O]-2 (g) -273.7 -279.2 ± 4.2 kJ/mol 80.0653 ± 0.0061 14265-45-3*0 Hydrogen fluoride HF (aq, 45 H2O) -321.94 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*906 Nitric acid HON(O)O (aq, 2 H2O) -193.72 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*803 Sulfur oxide peroxide OSOO (g) -26.0 -30.2 ± 2.3 kJ/mol 80.0642 ± 0.0061 175799-68-5*0 Formic acid HC(O)OH (aq, 100000 H2O) -425.39 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*861 Sulfur oxide peroxide OSOO (g, trans) -3.4 -7.1 ± 3.0 kJ/mol 80.0642 ± 0.0061 175799-68-5*1 Oxoethylidene HCC(O)H (g) 261.1 258.3 ± 1.1 kJ/mol 42.0367 ± 0.0016 39920-84-8*0 Nitric oxide NO (aq, undissoc) 79.213 ± 0.078 kJ/mol 30.00614 ± 0.00031 10102-43-9*1000 Sulfuryl dichloride cation [OS(O)Cl2]+ (g) 814.1 809.8 ± 3.2 kJ/mol 134.9697 ± 0.0063 *7791-25-5*0 Dichlorodioxosulfate [OS(O)Cl2]- (g) -604.8 -607.4 ± 3.5 kJ/mol 134.9707 ± 0.0063 12599-04-1*0 Nitrosodioxaziridine ONN(OO) (g, cis) 413.9 408.1 ± 3.2 kJ/mol 76.01168 ± 0.00091 132871-99-9*2 Disulfur oxide cation [SSO]+ (g) 970.53 969.25 ± 0.60 kJ/mol 80.1309 ± 0.0120 135758-60-0*0 Oxothioxosulfate [SSO]- (g) -231.95 -233.55 ± 0.87 kJ/mol 80.1319 ± 0.0120 12143-07-6*0 Hydrogen iodide HI (aq, 400 H2O) -56.318 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*832 2-Oxo-1-ethylium-1-yl [HCC(O)H]+ (g, quartet) 1289.4 1286.8 ± 2.5 kJ/mol 42.0361 ± 0.0016 214464-96-7*1 Hydrogen peroxide cation [HOOH]+ (g) 897.30 890.32 ± 0.51 kJ/mol 34.01413 ± 0.00062 12325-10-9*0 Hydrogen fluoride HF (aq, 20000 H2O) -326.65 ± 0.16 kJ/mol 20.006343 ± 0.000070 7664-39-3*852 2-Propenylidene CHCHCH2 (g) 417.6 410.6 ± 1.5 kJ/mol 40.0639 ± 0.0024 19527-08-3*0 Acetic acid CH3C(O)OH (aq, 2 H2O) -482.86 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*803 Oxoethylidene anion [HCC(O)H]- (g) 86.9 84.2 ± 2.1 kJ/mol 42.0372 ± 0.0016 106543-38-8*0 Hydrogen bromide HBr (aq, 111 H2O) -119.55 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*892 Sulfoniumyl [H2S]+ (g) 992.67 989.76 ± 0.18 kJ/mol 34.0813 ± 0.0060 26453-60-1*0 Dihydrogen sulfide ion [H2S]- (g) 108.2 106.9 ± 3.2 kJ/mol 34.0824 ± 0.0060 12311-21-6*0 2-Iodoethanol ICH2CH2OH (g) -131.9 -150.1 ± 2.5 kJ/mol 171.9650 ± 0.0017 624-76-0*0 Imidogen NH (g, singlet) 509.34 509.39 ± 0.17 kJ/mol 15.014680 ± 0.000099 13774-92-0*2 2-Propenylidene CHCHCH2 (g, triplet syn) 419.2 411.6 ± 2.3 kJ/mol 40.0639 ± 0.0024 19527-08-3*12 Hydrogen iodide HI (aq, 40 H2O) -55.695 ± 0.095 kJ/mol 127.912410 ± 0.000076 10034-85-2*821 1-Propen-1-yl-3-ylidene CHCHCH (g, doublet) 699.3 696.4 ± 3.4 kJ/mol 39.0559 ± 0.0024 84654-90-0*2 Iminomethyl HCNH (g) 275.80 272.20 ± 0.56 kJ/mol 28.03332 ± 0.00082 15691-95-9*0 Hydrogen fluoride HF (aq, 37 H2O) -321.91 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*890 Sulfuric acid cation [OS(O)(OH)2]+ (g) 400.8 387.8 ± 3.2 kJ/mol 98.0789 ± 0.0061 247933-66-0*0 Ethenol CH2CHOH (g) -113.27 -123.62 ± 0.37 kJ/mol 44.0526 ± 0.0017 557-75-5*0 Cyanoamidogen HNCN (g) 322.73 320.24 ± 0.63 kJ/mol 41.03212 ± 0.00082 12347-01-2*0 Cyanogen chloride cation [ClCN]+ (g) 1326.22 1327.55 ± 0.95 kJ/mol 61.4696 ± 0.0012 37612-72-9*0 Hydrogen fluoride HF (aq, 500 H2O) -322.35 ± 0.10 kJ/mol 20.006343 ± 0.000070 7664-39-3*833 Sulfate [OS(O)(O)O]-2 (aq) -909.16 ± 0.13 kJ/mol 96.0647 ± 0.0061 14808-79-8*800 Cyanoamidogen HNCN (g, quartet) 652.4 650.3 ± 1.2 kJ/mol 41.03212 ± 0.00082 12347-01-2*2 Cyanoaminylium [HNCN]+ (g) 1363.2 1360.9 ± 1.3 kJ/mol 41.03157 ± 0.00082 205443-18-1*0 Sulfuric acid OS(O)(OH)2 (aq, 10 H2O) -880.41 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*815 Sulfuric acid OS(O)(OH)2 (aq, 12 H2O) -882.02 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*816 Sulfuric acid OS(O)(OH)2 (aq, 15 H2O) -883.51 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*817 Sulfuric acid OS(O)(OH)2 (aq, 20 H2O) -884.80 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*818 Sulfuric acid OS(O)(OH)2 (aq, 25 H2O) -885.47 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*819 1,3,5-Hexatriyne cation [HCCCCCCH]+ (g) 1600.9 1605.6 ± 2.8 kJ/mol 74.0795 ± 0.0048 61866-06-6*0 Cyanogen bromide cation [BrCN]+ (g) 1331.3 1325.0 ± 1.4 kJ/mol 105.9209 ± 0.0013 34749-77-4*0 Diiodine I2 (aq, undissoc) 23.243 ± 0.082 kJ/mol 253.808940 ± 0.000060 7553-56-2*1000 2-Methyliumylidynehydrazin-2-ium-1-ide [HNNC]+ (g) 1544.2 1542.5 ± 1.7 kJ/mol 41.03157 ± 0.00082 *947408-73-3*0 Sulfuric acid OS(O)(OH)2 (aq, 150 H2O) -888.07 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*829 Sulfuric acid OS(O)(OH)2 (aq, 200 H2O) -888.51 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*830 Sulfuric acid OS(O)(OH)2 (aq, 300 H2O) -889.26 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*831 Sulfuric acid OS(O)(OH)2 (aq, 400 H2O) -889.86 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*832 Sulfuric acid OS(O)(OH)2 (aq, 500 H2O) -890.38 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*833 Sulfuric acid OS(O)(OH)2 (aq, 600 H2O) -890.87 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*834 (Iminomethyl)imidogen HNCHN (g) 420.1 413.3 ± 2.9 kJ/mol 42.04006 ± 0.00082 87570-07-8*0 Hydrogen iodide HI (aq, 500 H2O) -56.356 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*833 Sulfuric acid OS(O)(OH)2 (aq, 900 H2O) -891.94 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*838 1,3,5-Hexatriynylium [CCCCCCH]+ (g, triplet) 1913.8 1922.8 ± 8.2 kJ/mol 73.0716 ± 0.0048 81932-75-4*1 Nitric acid HON(O)O (aq, 4 H2O) -200.27 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*807 (Iminomethyl)imidogen HNCHN (g, syn-triplet) 430.4 423.5 ± 3.3 kJ/mol 42.04006 ± 0.00082 87570-07-8*12 Sulfuric acid OS(O)(OH)2 (aq, 4000 H2O) -897.00 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*843 Diazirenide [HC(NN)]- (g, triplet) 504.8 501.3 ± 2.9 kJ/mol 41.03267 ± 0.00082 130614-84-5*1 Acetic acid CH3C(O)OH (aq, 2.5 H2O) -482.95 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*804 Trioxygen difluoride FOOOF (g, cis) 113.6 107.8 ± 2.0 kJ/mol 85.99501 ± 0.00090 16829-28-0*2 Sulfuric acid OS(O)(OH)2 (aq, 20000 H2O) -903.21 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*852 Sulfuric acid OS(O)(OH)2 (aq, 50000 H2O) -905.91 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*855 Sulfuric acid OS(O)(OH)2 (aq, 100000 H2O) -907.21 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*861 Acetic acid CH3C(O)OH (aq, 55.51 H2O) -484.53 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*891 Oxonium [H3O]+ (aq) -285.801 ± 0.022 kJ/mol 19.02267 ± 0.00037 13968-08-6*800 Hydrogen chloride HCl (aq, 50 H2O) -165.187 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*822 Nitric acid HON(O)O (aq, 5 H2O) -201.93 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*809 Dioxohydrazine ONNO (g, trans) 192.3 188.7 ± 1.8 kJ/mol 60.01228 ± 0.00062 16824-89-8*1 Water anion [H2O]- (g) -50.1 -53.0 ± 4.3 kJ/mol 18.01583 ± 0.00033 12259-30-2*0 Propene CH3CHCH2 (cr,l) 7.74 4.04 ± 0.82 kJ/mol 42.0797 ± 0.0024 115-07-1*500 Acetic acid CH3C(O)OH (aq, 111 H2O) -484.66 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*892 Chlorine atom heptacation [Cl]+7 (g) 39520. 39522. ± 11. kJ/mol 35.44886 ± 0.00090 22537-27-5*0 Hydrogen iodide HI (aq, 555.1 H2O) -56.377 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*895 Hydrogen bromide HBr (aq, 3 H2O) -102.20 ± 0.13 kJ/mol 80.9119 ± 0.0010 10035-10-6*805 Methoxyethene CH2CHOCH3 (g, trans) -81.9 -99.0 ± 2.4 kJ/mol 58.0791 ± 0.0025 107-25-5*1 Hydrogen iodide HI (aq, 55.51 H2O) -55.854 ± 0.095 kJ/mol 127.912410 ± 0.000076 10034-85-2*891 Nitric acid HON(O)O (aq, 7 H2O) -203.75 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*812 Ammonium hydroxide NH4OH (aq, 55.51 H2O) -366.33 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*891 Hydrogen chloride HCl (aq, 2000 H2O) -166.681 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*841 Nitric acid HON(O)O (aq, 10 H2O) -204.98 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*815 Hydrogen fluoride HF (aq, 600 H2O) -322.43 ± 0.10 kJ/mol 20.006343 ± 0.000070 7664-39-3*834 Ketene CH2CO (g, ortho singlet) -45.22 -48.39 ± 0.11 kJ/mol 42.0367 ± 0.0016 463-51-4*22 2-Methanidylidynehydrazin-2-ium-1-ide [HNNC]- (g) 281.9 279.1 ± 1.4 kJ/mol 41.03267 ± 0.00082 *947408-74-4*0 1-Hydroxy-2-propanone CH3C(O)CH2OH (g) -354.40 -373.73 ± 0.83 kJ/mol 74.0785 ± 0.0025 116-09-6*0 Nitric acid HON(O)O (aq, 15 H2O) -205.67 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*817 Nitrosodioxaziridine ONN(OO) (g, gauche) 415.3 409.5 ± 2.8 kJ/mol 76.01168 ± 0.00091 132871-99-9*3 Cyanoamidogen anion [HNCN]- (g, triplet) 391.7 389.9 ± 1.8 kJ/mol 41.03267 ± 0.00082 67131-47-9*1 Oxonium [H3O]+ (g, ortho) 605.95 599.14 ± 0.17 kJ/mol 19.02267 ± 0.00037 13968-08-6*1 Sulfur hydroxide oxide OHS(O)(O)O (g) -474.5 -483.5 ± 1.6 kJ/mol 97.0715 ± 0.0061 12337-07-4*0 Sulfur hydroxide oxide OHS(O)(O)O (g, eclipsed) -473.7 -483.0 ± 2.5 kJ/mol 97.0715 ± 0.0061 12337-07-4*2 Sulfur hydroxide oxide cation [OHS(O)(O)O]+ (g) 658.6 648.3 ± 3.4 kJ/mol 97.0710 ± 0.0061 *12337-07-4*0 Sulfur hydroxide oxide cation [OHS(O)(O)O]+ (g, staggered) 663.1 652.2 ± 3.9 kJ/mol 97.0710 ± 0.0061 *12337-07-4*1 Cyanoamidogen anion [HNCN]- (g, t-triplet) 392.4 390.4 ± 6.2 kJ/mol 41.03267 ± 0.00082 67131-47-9*11 Hydrogen iodide HI (aq, 50000 H2O) -56.761 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*855 Sulfurous acid S(O)(OH)2 (g, trans) -507.1 -517.7 ± 1.3 kJ/mol 82.0801 ± 0.0061 7782-99-2*1 Sulfurous acid S(O)(OH)2 (g, gauche) -497.5 -507.5 ± 1.4 kJ/mol 82.0801 ± 0.0061 7782-99-2*3 Carbon trianion [C]-3 (g) 1813.2 1818.6 ± 5.9 kJ/mol 12.01235 ± 0.00080 50802-48-7*0 Hydrogen iodide HI (aq, 50 H2O) -55.803 ± 0.095 kJ/mol 127.912410 ± 0.000076 10034-85-2*822 Acetic acid CH3C(O)OH (aq, 3 H2O) -483.03 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*805 Sulfite [OS(O)O]-2 (aq) -635.24 ± 0.15 kJ/mol 80.0653 ± 0.0061 14265-45-3*800 Sulfurous acid S(O)(OH)2 (aq, 100 H2O) -610.09 ± 0.14 kJ/mol 82.0801 ± 0.0061 7782-99-2*828 Sulfurous acid S(O)(OH)2 (aq, 150 H2O) -610.81 ± 0.14 kJ/mol 82.0801 ± 0.0061 7782-99-2*829 Sulfurous acid S(O)(OH)2 (aq, 200 H2O) -611.35 ± 0.14 kJ/mol 82.0801 ± 0.0061 7782-99-2*830 Sulfurous acid S(O)(OH)2 (aq, 250 H2O) -611.78 ± 0.14 kJ/mol 82.0801 ± 0.0061 7782-99-2*908 Sulfurous acid S(O)(OH)2 (aq, 300 H2O) -612.15 ± 0.14 kJ/mol 82.0801 ± 0.0061 7782-99-2*831 Sulfurous acid S(O)(OH)2 (aq, 400 H2O) -612.75 ± 0.14 kJ/mol 82.0801 ± 0.0061 7782-99-2*832 Sulfurous acid S(O)(OH)2 (aq, 500 H2O) -613.26 ± 0.14 kJ/mol 82.0801 ± 0.0061 7782-99-2*833 Sulfurous acid S(O)(OH)2 (aq, 750 H2O) -614.20 ± 0.14 kJ/mol 82.0801 ± 0.0061 7782-99-2*836 Sulfurous acid S(O)(OH)2 (aq, 1000 H2O) -614.89 ± 0.14 kJ/mol 82.0801 ± 0.0061 7782-99-2*839 Sulfurous acid S(O)(OH)2 (aq, 1500 H2O) -615.98 ± 0.14 kJ/mol 82.0801 ± 0.0061 7782-99-2*840 Sulfurous acid S(O)(OH)2 (aq, 2000 H2O) -616.73 ± 0.14 kJ/mol 82.0801 ± 0.0061 7782-99-2*841 Sulfurous acid S(O)(OH)2 (aq, 3000 H2O) -617.78 ± 0.14 kJ/mol 82.0801 ± 0.0061 7782-99-2*842 Sulfurous acid S(O)(OH)2 (aq, 3500 H2O) -618.19 ± 0.14 kJ/mol 82.0801 ± 0.0061 7782-99-2*899 Sulfurous acid S(O)(OH)2 (aq, 4000 H2O) -618.52 ± 0.14 kJ/mol 82.0801 ± 0.0061 7782-99-2*843 Sulfurous acid S(O)(OH)2 (aq, 5000 H2O) -619.11 ± 0.14 kJ/mol 82.0801 ± 0.0061 7782-99-2*844 Sulfurous acid S(O)(OH)2 (aq, 7500 H2O) -620.08 ± 0.14 kJ/mol 82.0801 ± 0.0061 7782-99-2*847 Sulfurous acid S(O)(OH)2 (aq, 10000 H2O) -620.67 ± 0.14 kJ/mol 82.0801 ± 0.0061 7782-99-2*850 Sulfonic acid SH(O)(O)OH (g) -482.2 -494.8 ± 1.4 kJ/mol 82.0801 ± 0.0061 *7782-99-2*0 Hydrogen iodide HI (aq, 100000 H2O) -56.778 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*861 2-Ethylidenedioxidan-2-ium-1-ide CH3CHOO (g) 51.25 37.84 ± 0.54 kJ/mol 60.0520 ± 0.0017 68941-70-8*0 Hydrogen iodide HI (aq, 5 H2O) -47.72 ± 0.32 kJ/mol 127.912410 ± 0.000076 10034-85-2*809 3,3-Dioxidedioxathiirane OS(OO)O (g) -257.1 -265.2 ± 1.4 kJ/mol 96.0636 ± 0.0061 1177730-84-5*0 Hydrogen chloride HCl (aq, 10 H2O) -161.149 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*815 Acetic acid CH3C(O)OH (aq, 4 H2O) -483.13 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*807 Sulfur tetraoxide OS(O)(O)O (g) -228.2 -235.1 ± 2.0 kJ/mol 96.0636 ± 0.0061 12772-98-4*0 Oxoiodonium [IO]+ (g) 1065.2 1063.2 ± 1.5 kJ/mol 142.90332 ± 0.00030 81182-81-2*0 Sulfur tetraoxide OS(O)(O)O (g, triplet) -228.2 -235.1 ± 2.0 kJ/mol 96.0636 ± 0.0061 12772-98-4*1 Sulfur tetraoxide OS(O)(O)O (g, singlet) -163.8 -169.5 ± 2.9 kJ/mol 96.0636 ± 0.0061 12772-98-4*2 Hydrogen bromide HBr (aq, 20 H2O) -118.02 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*818 Ethoxyethene CH2CHOCH2CH3 (g) -117.7 -136.2 ± 1.5 kJ/mol 72.1057 ± 0.0033 109-92-2*0 Sulfur tetraoxide OS(O)(O)O (g, singlet C3v ?) -155.5 -164.4 ± 4.0 kJ/mol 96.0636 ± 0.0061 12772-98-4*23 Cyclopropane CH2(CH2CH2) (l) 41.51 35.83 ± 0.47 kJ/mol 42.0797 ± 0.0024 75-19-4*500 Diazomethyl HCNN (g) 467.86 465.31 ± 0.68 kJ/mol 41.03212 ± 0.00082 20813-32-5*0 Acetic acid CH3C(O)OH (aq, 200 H2O) -484.72 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*830 Ethylideneoxoniumyloxy [CH3CHOO]+ (g) 950.9 939.1 ± 2.2 kJ/mol 60.0514 ± 0.0017 1427752-17-7*0 Ethoxyethene CH2CHOCH2CH3 (g, cis-perp) -111.2 -135.1 ± 2.3 kJ/mol 72.1057 ± 0.0033 109-92-2*21 Ethoxyethene CH2CHOCH2CH3 (g, trans-trans) -110.7 -132.9 ± 2.6 kJ/mol 72.1057 ± 0.0033 109-92-2*1 Diazomethyl HCNN (g, quartet) 652.8 649.9 ± 1.3 kJ/mol 41.03212 ± 0.00082 20813-32-5*2 Dioxoperoxysulfate dianion [OS(O)OO]-2 (g) -209.1 -214.8 ± 2.1 kJ/mol 96.0647 ± 0.0061 *14808-79-8*0 Dioxoperoxysulfate dianion [OS(O)OO]-2 (g, Cs) -186.5 -192.2 ± 2.9 kJ/mol 96.0647 ± 0.0061 *14808-79-8*2 Hydrogen fluoride HF (aq, 900 H2O) -322.64 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*838 Methanethiol cation [CH3SH]+ (g) 901.89 891.85 ± 0.46 kJ/mol 48.1079 ± 0.0061 53369-41-8*0 Vinyl hydroperoxide CH2CHOOH (g) -26.04 -36.80 ± 0.69 kJ/mol 60.0520 ± 0.0017 66998-78-5*0 Hydrogen fluoride HF (aq, 50000 H2O) -328.57 ± 0.16 kJ/mol 20.006343 ± 0.000070 7664-39-3*855 Benzylidene C6H5CH (g) 473.0 457.8 ± 1.3 kJ/mol 90.1225 ± 0.0056 3101-08-4*0 Thioformaldehyde anion [CH2S]- (g) 75.8 72.8 ± 2.7 kJ/mol 46.0931 ± 0.0061 71928-47-7*0 Thioformaldehyde CH2S (g) 121.3 117.6 ± 2.0 kJ/mol 46.0926 ± 0.0061 865-36-1*0 Thioformaldehyde CH2S (g, triplet) 294.9 292.3 ± 2.0 kJ/mol 46.0926 ± 0.0061 865-36-1*3 Nitrosodioxaziridine ONN(OO) (g) 413.6 408.2 ± 1.8 kJ/mol 76.01168 ± 0.00091 132871-99-9*0 Ethanethiol cation [CH3CH2SH]+ (g) 867.12 850.96 ± 0.59 kJ/mol 62.1345 ± 0.0062 69762-64-7*0 Carbon C (g, quintuplet) 1114.956 1120.102 ± 0.040 kJ/mol 12.01070 ± 0.00080 7440-44-0*3 Diazomethyl HCNN (g, t-quartet) 653.0 650.0 ± 2.3 kJ/mol 41.03212 ± 0.00082 20813-32-5*21 Dimethyl sulfide cation [CH3SCH3]+ (g) 817.86 802.11 ± 0.48 kJ/mol 62.1345 ± 0.0062 34480-65-4*0 Hydrogen bromide HBr (aq, 2640 H2O) -120.24 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*957 Diazomethylium [HCNN]+ (g) 1395.8 1394.1 ± 1.3 kJ/mol 41.03157 ± 0.00082 271249-81-1*0 Bicyclo[1.1.0]buta-1,3-diene-2,4-diyl C(CC)C (g, triplet) 1133.1 1140.9 ± 2.7 kJ/mol 48.0428 ± 0.0032 12184-80-4*1 Difluoroaminylium [NF2]+ (g) 1157.82 1154.93 ± 0.71 kJ/mol 52.002998 ± 0.000070 31685-31-1*0 Ammonium hydroxide NH4OH (aq, 75 H2O) -366.35 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*825 Hydrogen bromide HBr (aq, 900 H2O) -120.08 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*838 Hydroxyamidogen HNOH (g) 101.27 94.43 ± 0.83 kJ/mol 32.02202 ± 0.00034 13940-32-4*0 Carbon disulfide cation [SCS]+ (g) 1088.28 1090.03 ± 0.68 kJ/mol 76.1422 ± 0.0120 12539-80-9*0 Sulfidocarbonothioyl [SCS]- (g) 73.5 75.0 ± 3.3 kJ/mol 76.1432 ± 0.0120 12122-00-8*0 Fulvenallene CH2CC(CHCHCHCH) (g) 368.7 354.4 ± 1.1 kJ/mol 90.1225 ± 0.0056 27041-32-3*0 Chlorine pentafluoride anion [FCl(F)(F)(F)F]- (g) -619.1 -622.6 ± 4.3 kJ/mol 130.44526 ± 0.00090 184851-42-1*0 Carbon monosulfide cation [CS]+ (g) 1371.34 1374.57 ± 0.78 kJ/mol 44.0762 ± 0.0061 12351-95-0*0 Carbon monosulfide anion [CS]- (g) 259.1 262.9 ± 2.2 kJ/mol 44.0772 ± 0.0061 12121-99-2*0 Acetic acid CH3C(O)OH (aq, 4.5 H2O) -483.17 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*808 Fluoronitrate [NF]- (g) 211.3 211.5 ± 2.8 kJ/mol 33.005692 ± 0.000070 33088-90-3*0 Platinum atom anion Pt- (g) 358.4 358.9 ± 1.7 kJ/mol 195.0785 ± 0.0020 40817-31-0*0 Tetrafluorohydrazine anion [NF2NF2]- (g, gauche) -184.5 -190.0 ± 3.3 kJ/mol 104.00764 ± 0.00014 39775-43-4*2 Platinum dimer cation [Pt2]+ (g) 1661.0 1659.6 ± 4.3 kJ/mol 390.1555 ± 0.0040 73146-08-4*0 Platinum dimer anion [Pt2]- (g) 640.3 639.8 ± 3.9 kJ/mol 390.1565 ± 0.0040 153298-77-2*0 Ammonium hydroxide NH4OH (aq, 3.5 H2O) -365.30 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*806 Acetic acid CH3C(O)OH (aq, 5 H2O) -483.21 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*809 Acetic acid CH3C(O)OH (aq, 300 H2O) -484.75 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*831 Hydrogen atom H (ad, Pt(111) fcc) -37.0 -40.2 ± 1.1 kJ/mol 1.007940 ± 0.000070 12385-13-6*1001000 Nitrogen atom heptacation [N]+7 (g) 143853.27 143855.13 ± 0.23 kJ/mol 14.002900 ± 0.000070 40549-08-4*0 Acetic acid CH3C(O)OH (aq, 6 H2O) -483.27 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*811 Isocyanoamidogen HNNC (g) 489.7 487.7 ± 1.2 kJ/mol 41.03212 ± 0.00082 947408-73-3*0 Hydrogen fluoride HF (aq, 700 H2O) -322.50 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*835 Hydrogen atom H (ad, Pt(111) atop) -32. -34. ± 20. kJ/mol 1.007940 ± 0.000070 12385-13-6*1002000 Isocyanoamidogen HNNC (g, quartet) 828.3 825.6 ± 1.3 kJ/mol 41.03212 ± 0.00082 947408-73-3*2 Benzocyclopropene CH2(CCHCHCHCHC) (g) 396.0 379.6 ± 1.5 kJ/mol 90.1225 ± 0.0056 4646-69-9*0 Hydroxyformyl HOCO (g) -181.14 -183.68 ± 0.40 kJ/mol 45.0174 ± 0.0010 2564-86-5*0 Water H2O (cr, eq.press.) -286.275 -292.715 ± 0.022 kJ/mol 18.01528 ± 0.00033 7732-18-5*509 Hydroxyformyl anion [HOCO]- (g) -319.53 -321.39 ± 0.56 kJ/mol 45.0180 ± 0.0010 78944-70-4*0 Hydrogen fluoride HF (aq, 250 H2O) -322.12 ± 0.10 kJ/mol 20.006343 ± 0.000070 7664-39-3*908 Argon cation Ar+ (g) 1520.571 1520.580 ± 0.000 kJ/mol 39.94745 ± 0.00100 14791-69-6*0 Argon dimer cation [Ar2]+ (g) 1393.760 1391.173 ± 0.018 kJ/mol 79.8955 ± 0.0020 17596-58-6*0 Argon atom dication [Ar]+2 (g) 4186.429 4186.468 ± 0.013 kJ/mol 39.94690 ± 0.00100 15056-24-3*0 Argon dimer Ar2 (g) -1.013 -6.347 ± 0.0051 kJ/mol 79.8960 ± 0.0020 12595-59-4*0 Argon anion Ar- (g, 2S1/2) 25. 25. ± 28. kJ/mol 39.94855 ± 0.00100 16544-90-4*1 Neon anion Ne- (g) 13. 13. ± 29. kJ/mol 20.18025 ± 0.00060 20205-95-2*0 Argon anion Ar- (g) 25. 25. ± 28. kJ/mol 39.94855 ± 0.00100 16544-90-4*0 Helium anion He- (g, 1s2.2s 2S1/2) 51. 51. ± 130. kJ/mol 4.0031506 ± 0.0000020 14452-58-5*1 Helium anion He- (g) 51. 51. ± 130. kJ/mol 4.0031506 ± 0.0000020 14452-58-5*0 Dihelium He2 (g, halo singlet) -0.000 -6.197 ± 0.000 kJ/mol 8.0052040 ± 0.0000040 12184-98-4*3 Dihelium He2 (g) -0.000 -6.197 ± 0.000 kJ/mol 8.0052040 ± 0.0000040 12184-98-4*0 Dichlorine Cl2 (cr,l) -30.21 -18.49 ± 0.51 kJ/mol 70.9054 ± 0.0018 7782-50-5*500 Helium anion He- (g, 1s.2s2 2S1/2) 1868.42 1868.42 ± 0.19 kJ/mol 4.0031506 ± 0.0000020 14452-58-5*2 Helium He (aq, undissoc) -0.702 ± 0.092 kJ/mol 4.0026020 ± 0.0000020 7440-59-7*1000 Dinitrogen N2 (aq, undissoc) -10.30 ± 0.32 kJ/mol 28.01348 ± 0.00014 7727-37-9*1000 Dihydrogen H2 (aq, undissoc) -4.104 ± 0.059 kJ/mol 2.01588 ± 0.00014 1333-74-0*1000 Neon Ne (aq, undissoc) -3.883 ± 0.092 kJ/mol 20.17970 ± 0.00060 7440-01-9*1000 Dioxygen O2 (aq, undissoc) -11.963 ± 0.041 kJ/mol 31.99880 ± 0.00060 7782-44-7*1000 Argon anion Ar- (g, 4S3/2) 1111.116 1111.116 ± 0.098 kJ/mol 39.94855 ± 0.00100 16544-90-4*2 Argon Ar (aq, undissoc) -12.249 ± 0.092 kJ/mol 39.94800 ± 0.00100 7440-37-1*1000 Krypton anion Kr- (g) 110. 110. ± 350. kJ/mol 83.8005 ± 0.1000 20205-93-0*0 Krypton Kr (aq, undissoc) -15.65 ± 0.11 kJ/mol 83.8000 ± 0.1000 7439-90-9*1000 Xenon Xe (aq, undissoc) -19.404 ± 0.092 kJ/mol 131.2900 ± 0.0200 7440-63-3*1000 Radon cation Rn+ (g) 1037.07 1037.07 ± 0.61 kJ/mol 221.9995 ± 0.1000 22541-65-7*0 Radon Rn (aq, undissoc) -21.33 ± 0.96 kJ/mol 222.0000 ± 0.1000 10043-92-2*1000 Hydron H+ (aq) 0 0 exact 1.007391 ± 0.000070 12408-02-5*800
References
1
B. Ruscic, R. E. Pinzon, M. L. Morton, G. von Laszewski, S. Bittner, S. G. Nijsure, K. A. Amin, M. Minkoff, and A. F. Wagner,
Introduction to Active Thermochemical Tables: Several "Key" Enthalpies of Formation Revisited.
J. Phys. Chem. A 108 , 9979-9997 (2004)
[DOI: 10.1021/jp047912y]
2
B. Ruscic, R. E. Pinzon, G. von Laszewski, D. Kodeboyina, A. Burcat, D. Leahy, D. Montoya, and A. F. Wagner,
Active Thermochemical Tables: Thermochemistry for the 21st Century.
J. Phys. Conf. Ser. 16 , 561-570 (2005)
[DOI: 10.1088/1742-6596/16/1/078]
3
B. Ruscic and D. H. Bross, Active Thermochemical Tables (ATcT) values based on ver. 1.202 of the Thermochemical Network (2024); available at ATcT.anl.gov
4
B. Ruscic and D. H. Bross
Accurate and Reliable Thermochemistry by Data Analysis of Complex Thermochemical Networks using Active Thermochemical Tables: The Case of Glycine Thermochemistry
Faraday Discuss. (in press) (2024)
[DOI: 10.1039/D4FD00110A]
5
B. Ruscic,
Uncertainty Quantification in Thermochemistry, Benchmarking Electronic Structure Computations, and Active Thermochemical Tables.
Int. J. Quantum Chem. 114 , 1097-1101 (2014)
[DOI: 10.1002/qua.24605]
6
B. Ruscic and D. H. Bross,
Thermochemistry
Computer Aided Chem. Eng. 45 , 3-114 (2019)
[DOI: 10.1016/B978-0-444-64087-1.00001-2]
Formula
The aggregate state is given in parentheses following the formula, such as: g - gas-phase, cr - crystal, l - liquid, etc.
Uncertainties
The listed uncertainties correspond to estimated 95% confidence limits, as customary in thermochemistry (see, for example, Ruscic [5 ] and Ruscic and Bross[6 ]).
Note that an uncertainty of ± 0.000 kJ/mol indicates that the estimated uncertainty is < ± 0.0005 kJ/mol.
Website Functionality Credits
The reorganization of the website was developed and implemented by David H. Bross (ANL).
The find function is based on the complete Species Dictionary entries for the appropriate version of the ATcT TN.
The molecule images are rendered by Indigo-depict .
The XYZ renderings are based on Jmol: an open-source Java viewer for chemical structures in 3D. http://www.jmol.org/ .
Acknowledgement
This work was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences and Biosciences under Contract No. DE-AC02-06CH11357.
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