ATcT [1 , 2 ] enthalpies of formation based on version 1.156 of the Thermochemical Network [3 ]
Below is a list of 0 K and 298.15 K enthalpies of formation
for all 3197 species included in version 1.156 (as of 09/01/2024). This version of ATcT results[3 ] was generated by additional expansion of version 1.148 to include species relevant to a recent study of the oxidation of ethylene [4 ] as well as new measurements that led to refining the thermochemistry of CF and SiF and their cations [5 ].
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) 711.400 716.885 ± 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) -66.541 -74.511 ± 0.044 kJ/mol 16.04246 ± 0.00085 74-82-8*0 Nitrogen atom N (g) 470.583 472.445 ± 0.022 kJ/mol 14.006740 ± 0.000070 17778-88-0*0 Water H2O (cr,l) -286.274 -285.802 ± 0.022 kJ/mol 18.01528 ± 0.00033 7732-18-5*500 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) -238.904 -241.807 ± 0.022 kJ/mol 18.01528 ± 0.00033 7732-18-5*0 Ethane CH3CH3 (g) -68.38 -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) 77.253 79.359 ± 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) 149.882 146.481 ± 0.050 kJ/mol 15.03452 ± 0.00083 2229-07-4*0 Methanol CH3OH (g) -189.90 -200.79 ± 0.13 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) 37.276 37.516 ± 0.022 kJ/mol 17.00734 ± 0.00031 3352-57-6*0 Formaldehyde CH2O (g) -105.381 -109.221 ± 0.095 kJ/mol 30.02598 ± 0.00087 50-00-0*0 Acetylene HCCH (g) 228.89 228.33 ± 0.12 kJ/mol 26.0373 ± 0.0016 74-86-2*0 Carbon monoxide CO (g) -113.799 -110.519 ± 0.026 kJ/mol 28.01010 ± 0.00085 630-08-0*0 Ethanol CH3CH2OH (g) -217.19 -234.90 ± 0.20 kJ/mol 46.0684 ± 0.0017 64-17-5*0 Hydrogen chloride HCl (g) -91.988 -92.172 ± 0.0062 kJ/mol 36.46064 ± 0.00090 7647-01-0*0 Benzene C6H6 (g) 100.71 83.20 ± 0.21 kJ/mol 78.1118 ± 0.0048 71-43-2*0 Propene CH3CHCH2 (g) 34.91 20.07 ± 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) 131.50 120.75 ± 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 Iodine I (g) 107.157 106.757 ± 0.0021 kJ/mol 126.904470 ± 0.000030 14362-44-8*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) 90.628 91.132 ± 0.065 kJ/mol 30.00614 ± 0.00031 10102-43-9*0 Acetaldehyde CH3CHO (g) -154.88 -165.41 ± 0.22 kJ/mol 44.0526 ± 0.0017 75-07-0*0 Propyne CH3CCH (g) 192.72 185.57 ± 0.21 kJ/mol 40.0639 ± 0.0024 74-99-7*0 Chloromethane CH3Cl (g) -74.72 -82.65 ± 0.18 kJ/mol 50.4872 ± 0.0012 74-87-3*0 Silicon Si (g) 450.32 454.66 ± 0.56 kJ/mol 28.08550 ± 0.00030 7440-21-3*0 Dioxidanyl HOO (g) 15.06 12.16 ± 0.14 kJ/mol 33.00674 ± 0.00060 3170-83-0*0 Acetone CH3C(O)CH3 (g) -199.94 -216.89 ± 0.26 kJ/mol 58.0791 ± 0.0025 67-64-1*0 Hydroxyde [OH]- (g) -139.065 -139.032 ± 0.022 kJ/mol 17.00789 ± 0.00031 14280-30-9*0 Methylamine CH3NH2 (g) -6.44 -21.14 ± 0.22 kJ/mol 31.05714 ± 0.00088 74-89-5*0 Nitrogen dioxide ONO (g) 36.867 34.060 ± 0.065 kJ/mol 46.00554 ± 0.00060 10102-44-0*0 Hydrogen iodide HI (g) 28.644 26.468 ± 0.036 kJ/mol 127.912410 ± 0.000076 10034-85-2*0 Allene CH2CCH2 (g) 197.48 190.02 ± 0.22 kJ/mol 40.0639 ± 0.0024 463-49-0*0 Hydrogen peroxide HOOH (g) -129.421 -135.407 ± 0.058 kJ/mol 34.01468 ± 0.00062 7722-84-1*0 Vinyl CH2CH (g) 301.27 297.23 ± 0.27 kJ/mol 27.0452 ± 0.0016 2669-89-8*0 Fluoromethane CH3F (g) -227.45 -235.48 ± 0.24 kJ/mol 34.03292 ± 0.00083 593-53-3*0 n-Butane CH3CH2CH2CH3 (g) -98.23 -125.54 ± 0.19 kJ/mol 58.1222 ± 0.0033 106-97-8*0 Toluene C6H5CH3 (g) 73.34 50.05 ± 0.31 kJ/mol 92.1384 ± 0.0056 108-88-3*0 Methylene CH2 (g, triplet) 391.081 391.627 ± 0.094 kJ/mol 14.02658 ± 0.00081 2465-56-7*1 Silane SiH4 (g) 42.63 33.02 ± 0.63 kJ/mol 32.11726 ± 0.00041 7803-62-5*0 Ozone OOO (g) 144.406 141.744 ± 0.039 kJ/mol 47.99820 ± 0.00090 10028-15-6*0 Methylene CH2 (g, singlet) 428.74 429.15 ± 0.11 kJ/mol 14.02658 ± 0.00081 2465-56-7*2 Fluoride F- (g) -250.911 -249.127 ± 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 1,3-Butadiene CH2CHCHCH2 (g) 125.61 111.14 ± 0.29 kJ/mol 54.0904 ± 0.0032 106-99-0*0 Ketene CH2CO (g) -45.33 -48.39 ± 0.11 kJ/mol 42.0367 ± 0.0016 463-51-4*0 Nitrilomethyl CN (g) 436.74 440.02 ± 0.14 kJ/mol 26.01744 ± 0.00080 2074-87-5*0 Methoxy CH3O (g) 29.01 21.64 ± 0.26 kJ/mol 31.03392 ± 0.00088 2143-68-2*0 Hydrogen chloride HCl (aq, 100 H2O) -165.755 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*828 Acetonitrile CH3CN (g) 81.15 74.09 ± 0.23 kJ/mol 41.0520 ± 0.0016 75-05-8*0 Bromomethane CH3Br (g) -20.53 -35.93 ± 0.20 kJ/mol 94.9385 ± 0.0013 74-83-9*0 Hydroxymethyl CH2OH (g) -10.07 -16.37 ± 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) -56.642 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*844 Formic acid HC(O)OH (g, syn) -371.03 -378.34 ± 0.21 kJ/mol 46.0254 ± 0.0010 64-18-6*1 Phenyl C6H5 (g) 352.50 339.14 ± 0.61 kJ/mol 77.1039 ± 0.0048 2396-01-2*0 Hydrogen fluoride HF (l) -303.198 ± 0.099 kJ/mol 20.006343 ± 0.000070 7664-39-3*590 Methoxide [CH3O]- (g) -122.38 -130.11 ± 0.26 kJ/mol 31.03447 ± 0.00088 3315-60-4*0 iso-Butane CH(CH3)3 (g) -105.86 -134.46 ± 0.27 kJ/mol 58.1222 ± 0.0033 75-28-5*0 Acetic acid CH3C(O)OH (aq, 100 H2O) -484.66 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*828 Hydrogen bromide HBr (aq, 3000 H2O) -120.26 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*842 Formic acid HC(O)OH (aq, 100 H2O) -425.29 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*828 Hypochlorous acid HOCl (g) -73.841 -76.781 ± 0.024 kJ/mol 52.46004 ± 0.00095 7790-92-3*0 Tetrafluoromethane CF4 (g) -927.62 -933.59 ± 0.23 kJ/mol 88.00431 ± 0.00080 75-73-0*0 Formyl HCO (g) 41.389 41.763 ± 0.095 kJ/mol 29.01804 ± 0.00086 2597-44-6*0 Amidogen NH2 (g) 188.92 186.03 ± 0.11 kJ/mol 16.02262 ± 0.00016 13770-40-6*0 Acetic acid CH3C(O)OH (g, syn) -418.51 -432.67 ± 0.36 kJ/mol 60.0520 ± 0.0017 64-19-7*1 n-Propyl CH3CH2CH2 (g) 118.46 101.06 ± 0.39 kJ/mol 43.0877 ± 0.0024 2143-61-5*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 Ethynyl CCH (g) 563.77 567.88 ± 0.15 kJ/mol 25.0293 ± 0.0016 2122-48-7*0 Propargyl CH2CCH (g) 354.08 351.49 ± 0.32 kJ/mol 39.0559 ± 0.0024 2932-78-7*0 Cyclopropane CH2(CH2CH2) (g) 71.06 53.94 ± 0.32 kJ/mol 42.0797 ± 0.0024 75-19-4*0 Allyl CH2CHCH2 (g) 179.92 168.20 ± 0.33 kJ/mol 41.0718 ± 0.0024 1981-80-2*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 iso-Propyl CH3CHCH3 (g) 105.67 88.80 ± 0.38 kJ/mol 43.0877 ± 0.0024 2025-55-0*0 Ethenol CH2CHOH (g, syn) -113.31 -124.44 ± 0.38 kJ/mol 44.0526 ± 0.0017 557-75-5*1 Ethylium [CH3CH2]+ (g) 915.18 903.10 ± 0.29 kJ/mol 29.0606 ± 0.0016 14936-94-8*0 Methanimine CH2NH (g) 96.40 88.49 ± 0.34 kJ/mol 29.04126 ± 0.00083 2053-29-4*0 Ethylamine CH3CH2NH2 (g) -28.03 -49.80 ± 0.45 kJ/mol 45.0837 ± 0.0017 75-04-7*0 Fluoroform CHF3 (g) -689.28 -696.23 ± 0.40 kJ/mol 70.01385 ± 0.00080 75-46-7*0 Oxomethylium [HCO]+ (g) 827.765 827.181 ± 0.095 kJ/mol 29.01749 ± 0.00086 17030-74-9*0 Acetyl CH3CO (g) -3.61 -10.18 ± 0.29 kJ/mol 43.0446 ± 0.0016 3170-69-2*0 Trifluoromethyl CF3 (g) -464.92 -467.71 ± 0.43 kJ/mol 69.00591 ± 0.00080 2264-21-3*0 Methylidyne CH (g) 592.990 596.324 ± 0.081 kJ/mol 13.01864 ± 0.00080 3315-37-5*0 Methyl hydroperoxide CH3OOH (g) -114.85 -127.67 ± 0.43 kJ/mol 48.0413 ± 0.0010 3031-73-0*0 Cyclopentadiene CH2(CHCHCHCH) (g) 151.77 134.65 ± 0.53 kJ/mol 66.1011 ± 0.0040 542-92-7*0 Phenol C6H5OH (g) -74.39 -92.98 ± 0.63 kJ/mol 94.1112 ± 0.0048 108-95-2*0 Tetrachloromethane CCl4 (g) -89.41 -91.58 ± 0.42 kJ/mol 153.8215 ± 0.0037 56-23-5*0 Benzaldehyde C6H5C(O)H (g) -19.16 -36.96 ± 0.68 kJ/mol 106.1219 ± 0.0056 100-52-7*0 Formamide CH(O)NH2 (g) -178.62 -188.98 ± 0.34 kJ/mol 45.04066 ± 0.00088 75-12-7*0 Oxonium [H3O]+ (g) 605.89 599.14 ± 0.17 kJ/mol 19.02267 ± 0.00037 13968-08-6*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 -61.75 ± 0.48 kJ/mol 96.9113 ± 0.0010 13517-11-8*0 Methylperoxy CH3OO (g) 22.52 13.07 ± 0.34 kJ/mol 47.0333 ± 0.0010 2143-58-0*0 Methoxymethane CH3OCH3 (g) -166.38 -183.89 ± 0.36 kJ/mol 46.0684 ± 0.0017 115-10-6*0 Cyanoacetylene HCCCN (g) 372.25 373.99 ± 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 Dioxymethyl CH2OO (g) 111.66 104.66 ± 0.56 kJ/mol 46.0254 ± 0.0010 56077-92-0*0 Nitric acid HON(O)O (g) -124.45 -134.17 ± 0.17 kJ/mol 63.01288 ± 0.00091 7697-37-2*0 Hydroxyformyl HOCO (g, trans) -181.15 -184.12 ± 0.40 kJ/mol 45.0174 ± 0.0010 2564-86-5*1 Vinyl chloride CH2CHCl (g) 29.39 21.80 ± 0.27 kJ/mol 62.4979 ± 0.0018 75-01-4*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) -42.71 -56.14 ± 0.46 kJ/mol 45.0605 ± 0.0017 2348-46-1*1 Vinylacetylene CH2CHCCH (g) 296.48 289.72 ± 0.53 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 Oxygen atom anion O- (g) 105.868 108.096 ± 0.0021 kJ/mol 15.99995 ± 0.00030 14337-01-0*0 Ethoxide [CH3CH2O]- (g) -163.77 -178.71 ± 0.44 kJ/mol 45.0610 ± 0.0017 16331-64-9*0 1,3-Butadiyne HCCCCH (g) 458.38 460.11 ± 0.49 kJ/mol 50.0587 ± 0.0032 460-12-8*0 Isocyanic acid HNCO (g) -115.93 -118.92 ± 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) -603.35 -606.45 ± 0.40 kJ/mol 66.00691 ± 0.00085 353-50-4*0 Methylium [CH3]+ (g) 1099.354 1095.411 ± 0.045 kJ/mol 15.03397 ± 0.00083 14531-53-4*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) -206.23 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*839 Iodomethane CH3I (g) 24.42 14.88 ± 0.18 kJ/mol 141.93899 ± 0.00083 74-88-4*0 Isobutene CH2C(CH3)2 (g) 4.32 -16.75 ± 0.32 kJ/mol 56.1063 ± 0.0032 115-11-7*0 2-Hydroxyethyl CH2CH2OH (g, gauche-syn) -12.89 -26.15 ± 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) -86.91 -93.77 ± 0.34 kJ/mol 84.9320 ± 0.0020 75-09-2*0 Chlorobenzene C6H5Cl (g) 67.27 52.32 ± 0.61 kJ/mol 112.5566 ± 0.0049 108-90-7*0 Hydrogen chloride HCl (aq, 600 H2O) -166.449 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*834 Oxirane O(CH2CH2) (g) -39.78 -52.34 ± 0.34 kJ/mol 44.0526 ± 0.0017 75-21-8*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) 176.04 162.55 ± 0.42 kJ/mol 54.0904 ± 0.0032 590-19-2*0 Ethynide [CCH]- (g) 277.32 280.74 ± 0.19 kJ/mol 25.0299 ± 0.0016 29075-95-4*0 Dimethylamine (CH3)2NH (g) 4.66 -16.98 ± 0.47 kJ/mol 45.0837 ± 0.0017 124-40-3*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 Trihydrogen cation [H3]+ (g) 1110.304 1106.696 ± 0.013 kJ/mol 3.02327 ± 0.00021 28132-48-1*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) 244.29 230.86 ± 0.38 kJ/mol 77.1044 ± 0.0048 30922-78-2*0 Cyclopropene CH2(CHCH) (g) 292.58 283.85 ± 0.42 kJ/mol 40.0639 ± 0.0024 2781-85-3*0 Methyl formate HC(O)OCH3 (g, syn) -346.85 -359.90 ± 0.61 kJ/mol 60.0520 ± 0.0017 107-31-3*1 Fluoromethylidyne CF (g) 243.19 246.79 ± 0.11 kJ/mol 31.00910 ± 0.00080 3889-75-6*0 Acrolein CH2CHCHO (g, trans) -55.12 -65.52 ± 0.64 kJ/mol 56.0633 ± 0.0024 107-02-8*1 Sulfur S (g) 276.83 279.08 ± 0.14 kJ/mol 32.0660 ± 0.0060 7704-34-9*0 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) -1608.75 -1614.26 ± 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 Ammonium [NH4]+ (g) 643.03 631.72 ± 0.20 kJ/mol 18.03795 ± 0.00029 14798-03-9*0 Nitrous acid HONO (g, trans) -72.985 -79.128 ± 0.078 kJ/mol 47.01348 ± 0.00061 7782-77-6*1 Methylamidogen CH3NH (g) 187.98 177.33 ± 0.40 kJ/mol 30.04920 ± 0.00085 15622-51-2*0 Hydroxymethylium [CH2OH]+ (g) 717.80 709.86 ± 0.17 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) 159.57 146.61 ± 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 Silyl SiH3 (g) 204.69 199.21 ± 0.80 kJ/mol 31.10932 ± 0.00037 13765-44-1*0 Sulfurous acid S(O)(OH)2 (aq, 2500 H2O) -617.30 ± 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 Nitrosyl hydride HNO (g) 109.94 106.97 ± 0.11 kJ/mol 31.01408 ± 0.00032 14332-28-6*0 Butatriene CH2CCCH2 (g) 328.45 322.19 ± 0.56 kJ/mol 52.0746 ± 0.0032 2873-50-9*0 Cyclopentadienyl CH(CHCHCHCH) (g) 275.45 262.34 ± 0.85 kJ/mol 65.0932 ± 0.0040 2143-53-5*0 Ethoxy CH3CH2O (g, X 2A") 1.36 -12.55 ± 0.42 kJ/mol 45.0605 ± 0.0017 2154-50-9*51 Phosgene CCl2O (g) -217.50 -219.20 ± 0.24 kJ/mol 98.9155 ± 0.0020 75-44-5*0 1-Hydroxy-2-propanone CH3C(O)CH2OH (g, syn-syn) -354.45 -373.84 ± 0.84 kJ/mol 74.0785 ± 0.0025 116-09-6*11 Cyanoamidogen HNCN (g, doublet) 322.71 320.23 ± 0.63 kJ/mol 41.03212 ± 0.00082 12347-01-2*1 Chloroform CHCl3 (g) -94.62 -99.52 ± 0.40 kJ/mol 119.3767 ± 0.0028 67-66-3*0 Tetrafluoroethylene CF2CF2 (g) -670.83 -674.23 ± 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 Acrylonitrile CH2CHCN (g, singlet) 194.03 187.26 ± 0.60 kJ/mol 53.0627 ± 0.0024 107-13-1*1 Silanol SiH3OH (g) -271.1 -282.7 ± 1.2 kJ/mol 48.11666 ± 0.00051 14475-38-8*0 Naphthalene C6H4(C4H4) (g) 171.21 147.73 ± 0.55 kJ/mol 128.1705 ± 0.0080 91-20-3*0 1,2-Propadiene-1,3-diylidene CCC (g) 814.43 823.38 ± 0.49 kJ/mol 36.0321 ± 0.0024 12075-35-3*0 Methylidyne CH (g, quartet) 664.72 668.05 ± 0.52 kJ/mol 13.01864 ± 0.00080 3315-37-5*2 Vinyl anion [CH2CH]- (g) 237.00 232.59 ± 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 80.59 ± 0.60 kJ/mol 57.1143 ± 0.0033 2492-36-6*0 neo-Pentane C(CH3)4 (g) -134.25 -167.13 ± 0.38 kJ/mol 72.1488 ± 0.0041 463-82-1*0 trans-2-Butene CH3CHCHCH3 (g, trans) 9.68 -10.88 ± 0.28 kJ/mol 56.1063 ± 0.0032 624-64-6*0 1-Butene CH2CHCH2CH3 (g) 21.23 0.28 ± 0.33 kJ/mol 56.1063 ± 0.0032 106-98-9*0 Benzyl C6H5CH2 (g) 230.05 211.23 ± 0.52 kJ/mol 91.1305 ± 0.0056 2154-56-5*0 Ethyl hydroperoxide CH3CH2OOH (g) -142.67 -161.10 ± 0.72 kJ/mol 62.0678 ± 0.0018 3031-74-1*0 Ethylperoxy CH3CH2OO (g, gauche) -6.23 -22.26 ± 0.64 kJ/mol 61.0599 ± 0.0017 3170-61-4*3 Formate [HC(O)O]- (g) -463.13 -466.77 ± 0.55 kJ/mol 45.0180 ± 0.0010 71-47-6*0 Methyl acetate CH3C(O)OCH3 (g, syn) -394.15 -413.02 ± 0.56 kJ/mol 74.0785 ± 0.0025 79-20-9*1 Aziridine NH(CH2CH2) (g) 143.57 127.03 ± 0.85 kJ/mol 43.0678 ± 0.0016 151-56-4*0 Ethyl bromide CH3CH2Br (g) -40.98 -62.92 ± 0.24 kJ/mol 108.9651 ± 0.0019 74-96-4*0 Vinyl bromide CH2CHBr (g) 88.79 73.98 ± 0.56 kJ/mol 106.9492 ± 0.0019 593-60-2*0 Methyl nitrite CH3ONO (g, cis) -55.42 -67.20 ± 0.43 kJ/mol 61.0401 ± 0.0010 624-91-9*2 Propadienone CH2CCO (g) 132.22 130.58 ± 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 Hypoiodous acid HOI (g) -53.7 -58.4 ± 2.8 kJ/mol 143.91181 ± 0.00031 14332-21-9*0 Nitrite [ONO]- (g) -182.63 -185.43 ± 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 Aminomethyl CH2NH2 (g) 159.43 149.59 ± 0.35 kJ/mol 30.04920 ± 0.00085 10507-29-6*0 cis-2-Butene CH3CHCHCH3 (g, cis) 14.42 -6.85 ± 0.38 kJ/mol 56.1063 ± 0.0032 590-18-1*0 1-Butyne CH3CH2CCH (g) 180.42 166.83 ± 0.56 kJ/mol 54.0904 ± 0.0032 107-00-6*0 n-Hexane CH3CH2CH2CH2CH2CH3 (g) -129.90 -166.77 ± 0.32 kJ/mol 86.1754 ± 0.0049 110-54-3*0 Methanetetraylbisamidogen NCN (g) 451.38 451.78 ± 0.40 kJ/mol 40.02418 ± 0.00081 2669-76-3*0 Tetrabromomethane CBr4 (g) 143.4 113.7 ± 1.1 kJ/mol 331.6267 ± 0.0041 558-13-4*0 Vinyl fluoride CH2CHF (g) -134.50 -142.31 ± 0.45 kJ/mol 46.0436 ± 0.0016 75-02-5*0 Phenylium [C6H5]+ (g) 1149.27 1136.49 ± 0.85 kJ/mol 77.1034 ± 0.0048 17333-73-2*0 Fluorobenzene C6H5F (g) -96.02 -111.70 ± 0.39 kJ/mol 96.1023 ± 0.0048 462-06-6*0 Nitromethane CH3N(O)O (g) -60.75 -74.65 ± 0.42 kJ/mol 61.0401 ± 0.0010 75-52-5*0 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) 114.65 111.78 ± 0.29 kJ/mol 16.02317 ± 0.00016 17655-31-1*0 Methanium [CH5]+ (g) 922.00 911.76 ± 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) 361.30 354.30 ± 0.48 kJ/mol 28.0532 ± 0.0016 4218-50-2*1 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 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) -114.17 -146.05 ± 0.29 kJ/mol 72.1488 ± 0.0041 109-66-0*0 Methanediol CH2(OH)2 (g, C2 gauche) -378.47 -392.41 ± 0.62 kJ/mol 48.0413 ± 0.0010 463-57-0*1 Formic acid HC(O)OH (g, anti) -354.69 -361.80 ± 0.37 kJ/mol 46.0254 ± 0.0010 64-18-6*2 Cyanooxidanyl NCO (g) 126.97 127.44 ± 0.33 kJ/mol 42.01684 ± 0.00086 22400-26-6*0 Acetone enol CH3C(OH)CH2 (g, syn) -151.22 -168.51 ± 0.75 kJ/mol 58.0791 ± 0.0025 29456-04-0*1 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) -704.30 -709.41 ± 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 Acrylonitrile CH2CHCN (g) 194.03 187.26 ± 0.60 kJ/mol 53.0627 ± 0.0024 107-13-1*0 1,2,3-Butatrien-1-yl CH2CCCH (g) 497.56 497.58 ± 0.67 kJ/mol 51.0666 ± 0.0032 22112-56-7*0 Disilane SiH3SiH3 (g) 92.0 75.8 ± 1.3 kJ/mol 62.21864 ± 0.00073 1590-87-0*0 2,4-Hexadiyne CH3CCCCCH3 (g) 380.33 370.30 ± 0.83 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 Dioxygen cation [O2]+ (g) 1164.585 1165.221 ± 0.0092 kJ/mol 31.99825 ± 0.00060 12185-07-8*0 Ethynylene C2 (g) 819.999 828.464 ± 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) 1119.15 1115.70 ± 0.55 kJ/mol 27.0447 ± 0.0016 14604-48-9*0 Vinylidene CCH2 (g) 411.24 412.15 ± 0.30 kJ/mol 26.0373 ± 0.0016 2143-69-3*0 Hydroxymethylene HCOH (g, trans) 112.71 108.94 ± 0.27 kJ/mol 30.02598 ± 0.00087 19710-56-6*1 Peroxyformic acid HC(O)OOH (g, cis) -279.25 -288.60 ± 0.63 kJ/mol 62.0248 ± 0.0012 107-32-4*1 1,2-Propadienyl anion [CH2CCH]- (g) 266.08 263.02 ± 0.63 kJ/mol 39.0565 ± 0.0024 64066-06-4*0 Propadienylidene CH2CC (g) 554.47 555.61 ± 0.39 kJ/mol 38.0480 ± 0.0024 60731-10-4*0 1-Propanol CH3CH2CH2OH (g) -231.14 -254.98 ± 0.20 kJ/mol 60.0950 ± 0.0025 71-23-8*0 Cyclopentane CH2(CH2CH2CH2CH2) (g) -43.42 -75.99 ± 0.38 kJ/mol 70.1329 ± 0.0041 287-92-3*0 Vinoxy CH2CHO (g) 23.02 16.22 ± 0.56 kJ/mol 43.0446 ± 0.0016 6912-06-7*0 Propionaldehyde CH3CH2CHO (g) -171.10 -186.51 ± 0.20 kJ/mol 58.0791 ± 0.0025 123-38-6*0 Phenolate [C6H5O]- (g) -146.08 -161.55 ± 0.83 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) 467.85 465.30 ± 0.68 kJ/mol 41.03212 ± 0.00082 20813-32-5*1 Bromotrifluoromethane CF3Br (g) -638.79 -650.91 ± 0.39 kJ/mol 148.9099 ± 0.0013 75-63-8*0 Bromoform CHBr3 (g) 80.4 54.3 ± 1.1 kJ/mol 252.7306 ± 0.0031 75-25-2*0 Carbamoyl NH2CO (g) -7.77 -14.18 ± 0.74 kJ/mol 44.03272 ± 0.00087 2858-51-7*0 Tetrahedrane CH(CH(CHCH)) (g) 547.76 539.35 ± 0.91 kJ/mol 52.0746 ± 0.0032 157-39-1*0 Silylene SiH2 (g, singlet) 271.59 269.92 ± 0.81 kJ/mol 30.10138 ± 0.00033 13825-90-6*2 Trioxidane HOOOH (g, trans) -81.75 -90.60 ± 0.40 kJ/mol 50.01408 ± 0.00091 14699-99-1*1 Chlorine dioxide OClO (g) 101.41 98.94 ± 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 Ethylidene CH3CH (g, singlet) 373.65 366.42 ± 0.57 kJ/mol 28.0532 ± 0.0016 4218-50-2*2 (E)-Iminomethyl HCNH (g, trans) 275.81 272.19 ± 0.56 kJ/mol 28.03332 ± 0.00082 54980-10-8*0 Cyanogen NCCN (g) 308.20 310.14 ± 0.41 kJ/mol 52.0349 ± 0.0016 460-19-5*0 Water H2O (l) -285.802 ± 0.022 kJ/mol 18.01528 ± 0.00033 7732-18-5*590 Peroxyformyl HC(O)OO (g, syn) -100.42 -105.73 ± 0.67 kJ/mol 61.0168 ± 0.0012 56240-83-6*1 1-Methylethenyl CH3CCH2 (g) 263.04 252.64 ± 0.61 kJ/mol 41.0718 ± 0.0024 15552-77-9*0 Cyclopentene CH2(CH2CHCHCH2) (g) 59.88 35.62 ± 0.43 kJ/mol 68.1170 ± 0.0040 142-29-0*0 Trimethylamine (CH3)3N (g) 2.69 -26.16 ± 0.79 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) 229.87 231.05 ± 0.64 kJ/mol 82.9161 ± 0.0020 1605-72-7*2 Trifluoromethylium [CF3]+ (g) 409.61 406.40 ± 0.41 kJ/mol 69.00536 ± 0.00080 18851-76-8*0 Ethyl nitrite CH3CH2ONO (g, trans-cis) -81.14 -99.88 ± 0.87 kJ/mol 75.0666 ± 0.0017 109-95-5*1 Methylketene CH3CHCO (g) -54.10 -63.58 ± 0.63 kJ/mol 56.0633 ± 0.0024 6004-44-0*0 Disilene SiH2SiH2 (g, singlet) 288.8 280.1 ± 1.7 kJ/mol 60.20276 ± 0.00066 15435-77-5*2 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) -20.23 -36.74 ± 0.35 kJ/mol 62.1350 ± 0.0062 75-18-3*0 Dioxidanide [HOO]- (g) -88.92 -91.58 ± 0.34 kJ/mol 33.00729 ± 0.00060 14691-59-9*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) 984.496 984.490 ± 0.065 kJ/mol 30.00559 ± 0.00031 14452-93-8*0 Ozonide [OOO]- (g) -58.47 -60.83 ± 0.21 kJ/mol 47.99875 ± 0.00090 12596-80-4*0 Hydroxyoxomethylium [HOCO]+ (g) 600.69 597.60 ± 0.43 kJ/mol 45.0169 ± 0.0010 638-71-1*0 Aminooxy NH2O (g) 70.63 64.03 ± 0.62 kJ/mol 32.02202 ± 0.00034 13408-29-2*0 Hydroxyamidogen HNOH (g, trans) 101.28 94.45 ± 0.87 kJ/mol 32.02202 ± 0.00034 13940-32-4*1 Hydrazoic acid HNNN (g) 297.99 291.69 ± 0.48 kJ/mol 43.02816 ± 0.00022 7782-79-8*0 Acetylium [CH3CO]+ (g) 666.67 659.39 ± 0.42 kJ/mol 43.0441 ± 0.0016 15762-07-9*0 Aminomethylium [CH2NH2]+ (g) 763.63 751.65 ± 0.53 kJ/mol 30.04865 ± 0.00085 488821-23-4*0 Hydrogen isocyanide HNC (g) 192.07 192.45 ± 0.32 kJ/mol 27.02538 ± 0.00081 6914-07-4*0 Chloroacetylene HCCCl (g) 229.30 230.17 ± 0.45 kJ/mol 60.4820 ± 0.0018 593-63-5*0 Fluoroacetylene HCCF (g) 104.99 105.70 ± 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) 608.88 594.46 ± 0.38 kJ/mol 45.0600 ± 0.0017 18682-96-7*1 Ketenyl HCCO (g) 177.12 178.21 ± 0.54 kJ/mol 41.0287 ± 0.0016 51095-15-9*0 Hydroxymethoxy CH2(OH)O (g, gauche) -159.58 -169.54 ± 0.84 kJ/mol 47.0333 ± 0.0010 72144-78-6*3 Formic acid HC(O)OH (g) -371.03 -378.32 ± 0.21 kJ/mol 46.0254 ± 0.0010 64-18-6*0 1-Butanol CH3CH2CH2CH2OH (g) -244.50 -274.74 ± 0.24 kJ/mol 74.1216 ± 0.0033 71-36-3*0 Acetic acid CH3C(O)OH (g, anti) -397.70 -412.11 ± 0.51 kJ/mol 60.0520 ± 0.0017 64-19-7*2 Glycolaldehyde HC(O)CH2OH (g, syn-syn) -304.32 -317.59 ± 0.89 kJ/mol 60.0520 ± 0.0017 141-46-8*11 Methyl formate HC(O)OCH3 (g, anti) -326.6 -339.1 ± 1.1 kJ/mol 60.0520 ± 0.0017 107-31-3*2 Glyoxal OCHCHO (g, trans) -207.82 -213.45 ± 0.55 kJ/mol 58.0361 ± 0.0017 107-22-2*1 (Methylamino)methyl CH3NHCH2 (g) 168.80 152.35 ± 0.71 kJ/mol 44.0758 ± 0.0017 31277-24-4*0 Diazirinyl HC(NN) (g, 2A2) 491.08 487.69 ± 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) 73.71 73.24 ± 0.84 kJ/mol 118.3688 ± 0.0028 3170-80-7*0 1,1-Dichloroethane CH3CHCl2 (g) -120.16 -132.94 ± 0.43 kJ/mol 98.9586 ± 0.0024 75-34-3*0 Bromobenzene C6H5Br (g) 127.0 105.0 ± 1.3 kJ/mol 157.0079 ± 0.0049 108-86-1*0 Phenylethene C6H5CHCH2 (g) 169.91 148.58 ± 0.51 kJ/mol 104.1491 ± 0.0064 100-42-5*0 Phenylacetylene C6H5CCH (g) 332.79 317.63 ± 0.69 kJ/mol 102.1332 ± 0.0064 536-74-3*0 Acetophenone C6H5C(O)CH3 (g) -60.74 -83.92 ± 0.98 kJ/mol 120.1485 ± 0.0064 98-86-2*0 Difluorodioxidane FOOF (g) 35.37 31.65 ± 0.40 kJ/mol 69.99561 ± 0.00060 7783-44-0*0 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) 232.1 216.0 ± 1.1 kJ/mol 78.1118 ± 0.0048 497-20-1*0 Disilanyl SiH3SiH2 (g) 242.3 230.3 ± 1.5 kJ/mol 61.21070 ± 0.00069 73151-72-1*0 Silanone SiH2O (g) -93.79 -99.14 ± 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) 142.81 143.26 ± 0.18 kJ/mol 33.0739 ± 0.0060 13940-21-1*0 Methanethiol CH3SH (g) -10.38 -20.66 ± 0.46 kJ/mol 48.1085 ± 0.0061 74-93-1*0 Chlorous acid HOClO (g) 25.76 20.71 ± 0.63 kJ/mol 68.4594 ± 0.0011 13898-47-0*0 Iodooxidanyl IO (g) 127.05 125.12 ± 0.82 kJ/mol 142.90387 ± 0.00030 14696-98-1*0 Carbon monoxide cation [CO]+ (g) 1238.310 1241.590 ± 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) 242.09 238.43 ± 0.55 kJ/mol 28.03332 ± 0.00082 15845-29-1*0 Cyanogen iodide ICN (g) 222.5 222.0 ± 1.7 kJ/mol 152.92191 ± 0.00080 506-78-5*0 Dioxygen anion [O2]- (g) -43.36 -42.72 ± 0.17 kJ/mol 31.99935 ± 0.00060 11062-77-4*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) 857.16 838.88 ± 0.76 kJ/mol 43.0871 ± 0.0024 19252-52-9*0 Cyclopropyl CH(CH2CH2) (g) 303.92 291.29 ± 0.48 kJ/mol 41.0718 ± 0.0024 2417-82-5*0 2-Propynylidyne CCCH (g) 718.80 723.15 ± 0.71 kJ/mol 37.0400 ± 0.0024 53590-28-6*0 Fluorodioxidanyl FOO (g) 26.87 25.16 ± 0.26 kJ/mol 50.99720 ± 0.00060 15499-23-7*0 iso-Pentane CH3CH2CH(CH3)2 (g) -118.91 -152.96 ± 0.39 kJ/mol 72.1488 ± 0.0041 78-78-4*0 1-Hydroxyethylidene CH3COH (g, anti singlet) 57.44 47.06 ± 0.77 kJ/mol 44.0526 ± 0.0017 30967-49-8*21 Dicarbon monoxide CCO (g, triplet) 377.14 381.18 ± 0.83 kJ/mol 40.0208 ± 0.0016 12071-23-7*1 Acetic acid CH3C(O)OH (g) -418.51 -432.67 ± 0.36 kJ/mol 60.0520 ± 0.0017 64-19-7*0 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) 219.36 208.00 ± 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 Chloromethylene CHCl (g, singlet) 320.36 320.65 ± 0.89 kJ/mol 48.4713 ± 0.0012 2108-20-5*2 Dibromomethane CH2Br2 (g) 27.4 5.9 ± 1.1 kJ/mol 173.8346 ± 0.0022 74-95-3*0 1,1-Difluoroethene CH2CF2 (g) -343.65 -350.71 ± 0.63 kJ/mol 64.0341 ± 0.0016 75-38-7*0 Indane C6H4(CH2CH2CH2) (g) 90.90 59.87 ± 0.76 kJ/mol 118.1757 ± 0.0072 496-11-7*0 o-Tolualdehyde CH3C6H4C(O)H (g, ortho) -44.2 -66.4 ± 1.1 kJ/mol 120.1485 ± 0.0064 529-20-4*0 3-Buten-2-one CH3C(O)CHCH2 (g, trans) -95.32 -111.56 ± 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) -219.61 -237.12 ± 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 Hypofluorite [FO]- (g) -108.84 -108.67 ± 0.48 kJ/mol 34.99835 ± 0.00030 12763-66-5*0 1,3-Hexadiyne HCCCCCH2CH3 (g) 405.22 393.52 ± 0.95 kJ/mol 78.1118 ± 0.0048 4447-21-6*0 (E)-1-Methylallyl CH3CHCHCH2 (g, trans) 152.68 135.36 ± 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) -102.39 -104.20 ± 0.88 kJ/mol 142.90442 ± 0.00030 15065-65-3*0 Iodotrifluoromethane CF3I (g) -583.38 -589.26 ± 0.45 kJ/mol 195.91038 ± 0.00080 2314-97-8*0 Nitrogen atom cation N+ (g) 1872.911 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 88.14 ± 0.25 kJ/mol 30.00669 ± 0.00031 14967-78-3*0 Nitrogen sesquioxide ONN(O)O (g) 90.74 86.17 ± 0.15 kJ/mol 76.01168 ± 0.00091 10544-73-7*0 Hexafluoroethane CF3CF3 (g) -1334.28 -1342.58 ± 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) 328.19 328.62 ± 0.18 kJ/mol 14.02713 ± 0.00081 50928-07-9*0 Methylidyne anion [CH]- (g) 475.78 479.10 ± 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 Chloronium [HClH]+ (g) 881.5 878.4 ± 1.1 kJ/mol 37.46803 ± 0.00091 36658-55-6*0 Carbonic acid C(O)(OH)2 (g, cis-cis) -602.30 -612.47 ± 0.58 kJ/mol 62.0248 ± 0.0012 463-79-6*1 Methylperoxy anion [CH3OO]- (g) -89.68 -99.83 ± 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) 318.17 310.80 ± 0.67 kJ/mol 53.0825 ± 0.0032 82252-88-8*0 1,2-Butadienyl CH3CHCCH (g) 328.96 320.24 ± 0.63 kJ/mol 53.0825 ± 0.0032 4777-46-2*0 Chlorine atom cation Cl+ (g) 1370.807 1372.603 ± 0.0021 kJ/mol 35.45215 ± 0.00090 24203-47-2*0 Isoprene CH2C(CH3)CHCH2 (g) 96.28 75.76 ± 0.66 kJ/mol 68.1170 ± 0.0040 78-79-5*0 Oxirene O(CHCH) (g, singlet) 272.42 270.26 ± 0.60 kJ/mol 42.0367 ± 0.0016 157-18-6*2 Ethynol HCCOH (g, singlet) 95.31 92.83 ± 0.73 kJ/mol 42.0367 ± 0.0016 32038-79-2*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) -125.79 -127.45 ± 0.55 kJ/mol 45.0174 ± 0.0010 16499-21-1*1 Methoxyethane CH3CH2OCH3 (g) -194.29 -217.18 ± 0.52 kJ/mol 60.0950 ± 0.0025 540-67-0*0 Acetate [CH3C(O)O]- (g) -495.98 -505.11 ± 0.80 kJ/mol 59.0446 ± 0.0017 71-50-1*0 Cyanoamidogen anion [HNCN]- (g, singlet) 69.73 66.73 ± 0.72 kJ/mol 41.03267 ± 0.00082 67131-47-9*2 1,1,1-Trichloroethane CH3CCl3 (g) -133.99 -144.57 ± 0.51 kJ/mol 133.4033 ± 0.0031 71-55-6*0 Tetrachloroethene CCl2CCl2 (g) -20.59 -21.46 ± 0.99 kJ/mol 165.8322 ± 0.0039 127-18-4*0 Chlorodifluoromethane CHClF2 (g) -475.59 -481.78 ± 0.99 kJ/mol 86.4681 ± 0.0012 75-45-6*0 Fluoromethylene CHF (g, singlet) 148.41 148.70 ± 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) -196.00 -220.06 ± 0.52 kJ/mol 124.9645 ± 0.0019 540-51-2*0 Carbon suboxide OCCCO (g) -94.41 -92.29 ± 0.96 kJ/mol 68.0309 ± 0.0025 504-64-3*0 Ethylbenzene C6H5CH2CH3 (g) 58.43 29.97 ± 0.52 kJ/mol 106.1650 ± 0.0064 100-41-4*0 Phenoxy C6H5O (g) 71.38 56.09 ± 0.83 kJ/mol 93.1033 ± 0.0048 2122-46-5*0 m-Tolualdehyde CH3C6H4C(O)H (g, meta) -48.5 -71.4 ± 1.2 kJ/mol 120.1485 ± 0.0064 620-23-5*0 Chlorine trifluoride FCl(F)F (g) -158.63 -162.73 ± 0.86 kJ/mol 92.44791 ± 0.00090 7790-91-2*0 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) 135.52 133.35 ± 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) 396.12 388.19 ± 0.82 kJ/mol 52.0746 ± 0.0032 4095-06-1*0 Phenylperoxy C6H5OO (g) 153.8 136.8 ± 1.4 kJ/mol 109.1027 ± 0.0049 91422-02-5*0 Fluorosilylidyne SiF (g, doublet) -60.26 -58.43 ± 0.62 kJ/mol 47.08390 ± 0.00030 11128-24-8*1 Silylidyne SiH (g) 371.24 373.03 ± 0.67 kJ/mol 29.09344 ± 0.00031 13774-94-2*0 Bromosilane SiH3Br (g) -59.1 -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) 240.12 223.94 ± 0.66 kJ/mol 55.0984 ± 0.0032 71790-71-1*1 1-Butenyl CH3CH2CHCH (g, cis) 263.47 246.13 ± 0.68 kJ/mol 55.0984 ± 0.0032 2669-61-6*2 Disulfur S2 (g) 127.37 127.68 ± 0.27 kJ/mol 64.1320 ± 0.0120 23550-45-0*0 Sulfur monoxide SO (g) 5.95 6.00 ± 0.13 kJ/mol 48.0654 ± 0.0060 13827-32-2*0 Oxygen atom O (g, triplet) 246.844 249.229 ± 0.0021 kJ/mol 15.99940 ± 0.00030 17778-80-2*1 Ammonium [NH4]+ (aq) -133.075 ± 0.056 kJ/mol 18.03795 ± 0.00029 14798-03-9*800 Methylidyne CH (g, doublet) 592.990 596.324 ± 0.081 kJ/mol 13.01864 ± 0.00080 3315-37-5*1 Ethylidyne CH3C (g, quartet) 640.9 636.3 ± 1.1 kJ/mol 27.0452 ± 0.0016 67624-57-1*2 Hydroxyde [OH]- (aq) -229.758 ± 0.023 kJ/mol 17.00789 ± 0.00031 14280-30-9*800 Isocyanomethanide [CH2NC]- (g) 253.99 250.95 ± 0.89 kJ/mol 40.0446 ± 0.0016 81704-80-5*0 Peroxyformate [HC(O)OO]- (g, syn) -340.95 -346.40 ± 0.80 kJ/mol 61.0174 ± 0.0012 104960-05-6*1 Hydrogen peroxide cation [HOOH]+ (g, trans) 897.30 890.31 ± 0.51 kJ/mol 34.01413 ± 0.00062 12325-10-9*1 1-Methylethylidene CH3CCH3 (g, singlet) 316.08 302.17 ± 0.97 kJ/mol 42.0797 ± 0.0024 40852-89-9*2 Propylidene CH3CH2CH (g, triplet gauche) 349.51 335.82 ± 0.92 kJ/mol 42.0797 ± 0.0024 6700-78-3*11 Cycloprop-2-enylium [CH(CHCH)]+ (g) 1080.5 1075.4 ± 1.0 kJ/mol 39.0554 ± 0.0024 26810-74-2*0 Cyclobutene CH2(CH2CHCH) (g) 178.04 161.00 ± 0.60 kJ/mol 54.0904 ± 0.0032 822-35-5*0 1,3-Butadienyl CH2CHCHCH (g, trans-trans) 372.28 361.79 ± 0.87 kJ/mol 53.0825 ± 0.0032 86181-68-2*11 Cyclohexane CH2(CH2CH2CH2CH2CH2) (g) -83.22 -122.78 ± 0.29 kJ/mol 84.1595 ± 0.0049 110-82-7*0 Protonated oxirane [(CH2CH2)OH]+ (g) 725.73 709.56 ± 0.61 kJ/mol 45.0600 ± 0.0017 *38607-31-7*0 Methoxymethyl CH3OCH2 (g) 13.46 0.90 ± 0.86 kJ/mol 45.0605 ± 0.0017 16520-04-0*0 Methoxymethylene CH3OCH (g, anti singlet) 129.24 118.71 ± 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) -222.81 -250.23 ± 0.75 kJ/mol 74.1216 ± 0.0033 60-29-7*0 Cyanic acid HOCN (g) -12.31 -15.02 ± 0.43 kJ/mol 43.02478 ± 0.00086 420-05-3*0 Fulminic acid HCNO (g) 170.74 169.28 ± 0.44 kJ/mol 43.02478 ± 0.00086 51060-05-0*0 Isofulminic acid HONC (g) 235.26 233.55 ± 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) -232.52 -241.51 ± 0.39 kJ/mol 78.4973 ± 0.0019 75-36-5*0 Dioxoethyl OCHCO (g) -63.25 -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) 9.29 3.30 ± 0.50 kJ/mol 96.9427 ± 0.0024 75-35-4*0 Dichlorodifluoromethane CF2Cl2 (g) -488.93 -493.11 ± 0.45 kJ/mol 120.9129 ± 0.0020 75-71-8*0 Fluorodichloromethane CHFCl2 (g) -277.67 -283.12 ± 0.90 kJ/mol 102.9224 ± 0.0020 75-43-4*0 Difluoromethylene CF2 (g, singlet) -193.87 -193.40 ± 0.35 kJ/mol 50.00751 ± 0.00080 2154-59-8*2 Fluoromethylene CHF (g, triplet) 210.38 210.72 ± 0.65 kJ/mol 32.01704 ± 0.00080 13453-52-6*1 Formyl fluoride CHFO (g) -378.64 -382.22 ± 0.31 kJ/mol 48.01644 ± 0.00086 1493-02-3*0 Trioxidanide [HOOO]- (g, gauche) -120.3 -123.4 ± 1.6 kJ/mol 49.00669 ± 0.00090 89965-38-8*2 Indene C6H4(CHCHCH2) (g) 183.83 159.94 ± 0.74 kJ/mol 116.1598 ± 0.0072 95-13-6*0 p-Tolualdehyde CH3C6H4C(O)H (g, para) -49.2 -72.3 ± 1.2 kJ/mol 120.1485 ± 0.0064 104-87-0*0 o-Toluoyl CH3C6H4CO (g, ortho) 110.3 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 Acetonyl CH3C(O)CH2 (g) -18.43 -32.03 ± 0.76 kJ/mol 57.0712 ± 0.0024 3122-07-4*0 Propyl nitrite CH3CH2CH2ONO (g, gauche-trans-cis) -95.7 -120.7 ± 1.8 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) 447.87 445.39 ± 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) 547.40 544.74 ± 0.85 kJ/mol 51.0666 ± 0.0032 2810-61-9*1 3-Buten-1-ynyl CH2CHCC (g) 628.65 626.46 ± 0.99 kJ/mol 51.0666 ± 0.0032 108179-98-2*0 Methylsilane CH3SiH3 (g) -9.83 -26.01 ± 0.89 kJ/mol 46.14384 ± 0.00095 992-94-9*0 Fluorosilane SiH3F (g) -346.22 -355.61 ± 0.73 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) 174.47 158.01 ± 0.83 kJ/mol 44.0758 ± 0.0017 4422-53-1*0 2-Propanamine CH3CH(CH3)NH2 (g) -56.64 -83.43 ± 0.52 kJ/mol 59.1103 ± 0.0025 75-31-0*0 Sulfuric acid OS(O)(OH)2 (g) -715.5 -729.7 ± 1.1 kJ/mol 98.0795 ± 0.0061 7664-93-9*0 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) 470.583 472.445 ± 0.022 kJ/mol 14.006740 ± 0.000070 17778-88-0*1 Carbon dioxide cation [CO2]+ (g) 936.090 936.924 ± 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 Oxoniumyl ion [H2O]+ (g) 978.494 975.591 ± 0.024 kJ/mol 18.01473 ± 0.00033 56583-62-1*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) -36.74 -43.71 ± 0.84 kJ/mol 47.01348 ± 0.00061 90266-90-3*0 Carbon anion C- (g) 589.624 594.770 ± 0.040 kJ/mol 12.01125 ± 0.00080 14337-00-9*0 Hydrogen isocyanide cation [HNC]+ (g) 1351.54 1351.49 ± 0.83 kJ/mol 27.02483 ± 0.00081 74158-11-5*0 Cyanomethanide [CH2CN]- (g) 113.69 110.86 ± 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 Dioxygen O2 (g, triplet) 0.000 0.000 ± 0.000 kJ/mol 31.99880 ± 0.00060 7782-44-7*1 n-Propylide [CH3CH2CH2]- (g) 123.1 105.4 ± 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 Dichloride [Cl2]- (g) -231.91 -230.84 ± 0.34 kJ/mol 70.9059 ± 0.0018 12595-89-0*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) 253.7 244.9 ± 1.1 kJ/mol 53.0830 ± 0.0032 65114-66-1*0 Chloro hypochlorite ClOCl (g) 79.79 77.98 ± 0.36 kJ/mol 86.9048 ± 0.0018 7791-21-1*0 Cycloheptatriene CH2(CHCHCHCHCHCH) (g) 207.71 184.28 ± 0.91 kJ/mol 92.1384 ± 0.0056 544-25-2*0 n-Octane CH3(CH2)6CH3 (g) -161.06 -207.89 ± 0.51 kJ/mol 114.2285 ± 0.0065 111-65-9*0 Ethoxy CH3CH2O (g, A 2A') 5.63 -8.81 ± 0.43 kJ/mol 45.0605 ± 0.0017 2154-50-9*52 Ethenol CH2CHOH (g, anti) -108.88 -119.60 ± 0.50 kJ/mol 44.0526 ± 0.0017 557-75-5*2 Hydroperoxymethyl CH2OOH (g) 73.24 65.94 ± 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) 172.81 164.53 ± 0.98 kJ/mol 43.0446 ± 0.0016 31586-84-2*0 Ketene CH2CO (g, triplet) 182.0 179.0 ± 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 Dioxirane CH2(OO) (g) 9.40 1.73 ± 0.53 kJ/mol 46.0254 ± 0.0010 157-26-6*0 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) -248.62 -272.72 ± 0.26 kJ/mol 60.0950 ± 0.0025 67-63-0*0 Methyl acetate CH3C(O)OCH3 (g, anti) -363.3 -382.0 ± 1.2 kJ/mol 74.0785 ± 0.0025 79-20-9*2 Hydroperoxonium [H2OOH]+ (g, trans) 738.2 727.9 ± 1.2 kJ/mol 35.02207 ± 0.00064 70850-26-9*1 Carboxymethyl CH2C(O)OH (g, syn) -226.6 -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) 294.72 286.09 ± 0.92 kJ/mol 42.0599 ± 0.0016 180385-92-6*0 Chlorooxy hypochlorite ClOOCl (g) 134.57 131.34 ± 0.56 kJ/mol 102.9042 ± 0.0019 12292-23-8*0 Nitrilomethylimidogen NCHN (g, quartet) 581.6 578.4 ± 1.5 kJ/mol 41.03212 ± 0.00082 324529-58-0*2 Cyanoacetylide [CCCN]- (g) 300.4 305.6 ± 1.1 kJ/mol 50.0394 ± 0.0024 12373-53-4*0 Chloromethylidyne CCl (g) 430.63 434.38 ± 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) -283.31 -286.46 ± 0.76 kJ/mol 137.3672 ± 0.0028 75-69-4*0 Formyl chloride CHClO (g) -179.87 -183.08 ± 0.67 kJ/mol 64.4707 ± 0.0012 2565-30-2*0 2-Chloroethanol ClCH2CH2OH (g) -249.79 -266.50 ± 0.59 kJ/mol 80.5132 ± 0.0019 107-07-3*0 Butadiynyl CCCCH (g) 801.89 808.49 ± 0.96 kJ/mol 49.0507 ± 0.0032 53561-65-2*0 o-Benzyne C6H4 (g, singlet) 468.26 459.34 ± 0.86 kJ/mol 76.0960 ± 0.0048 462-80-6*2 Tropyl CH(CHCHCHCHCHCH) (g) 296.68 279.24 ± 0.99 kJ/mol 91.1305 ± 0.0056 3551-27-7*0 Peroxyhypochlorous acid HOOCl (g) 3.97 -1.30 ± 0.95 kJ/mol 68.4594 ± 0.0011 67952-07-2*0 m-Toluoyl CH3C6H4CO (g, meta) 109.3 90.7 ± 1.4 kJ/mol 119.1406 ± 0.0064 67958-04-7*0 Iodobenzene C6H5I (g) 178.58 162.59 ± 0.99 kJ/mol 204.0084 ± 0.0048 591-50-4*0 1-Hydroxy-1-methylethyl CH3C(OH)CH3 (g) -78.23 -96.48 ± 0.79 kJ/mol 59.0871 ± 0.0025 5131-95-3*0 Trifluoroethene CF2CHF (g) -493.5 -498.6 ± 1.4 kJ/mol 82.0245 ± 0.0016 359-11-5*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 Isocyanoethene CH2CHNC (g) 285.33 278.83 ± 0.92 kJ/mol 53.0627 ± 0.0024 14668-82-7*0 1-Isocyanoethylidene CH3CNC (g, singlet) 528.0 523.2 ± 1.1 kJ/mol 53.0627 ± 0.0024 *498544-34-6*2 2-Cyanovinyl CHCHCN (g, anti) 448.30 445.84 ± 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) -98.38 -97.22 ± 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) 246.59 227.68 ± 0.72 kJ/mol 55.0984 ± 0.0032 4548-06-5*0 1-Propanamine CH3CH2CH2NH2 (g) -42.21 -69.95 ± 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 Perchloryl OCl(O)O (g) 191.76 186.09 ± 0.62 kJ/mol 83.4509 ± 0.0013 13932-10-0*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) -206.55 ± 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) 1092.47 1089.54 ± 0.67 kJ/mol 31.01353 ± 0.00032 63559-87-5*0 Fluoronium [HFH]+ (g, singlet) 774.04 771.10 ± 0.91 kJ/mol 21.01373 ± 0.00014 12206-67-6*2 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) 1797.853 1803.451 ± 0.040 kJ/mol 12.01015 ± 0.00080 14067-05-1*0 Chlorate [OCl(O)O]- (g) -208.2 -213.7 ± 1.5 kJ/mol 83.4514 ± 0.0013 14866-68-3*0 Trioxidane HOOOH (g, cis) -72.68 -81.16 ± 0.78 kJ/mol 50.01408 ± 0.00091 14699-99-1*2 Ethylidyne CH3C (g) 508.65 504.95 ± 0.80 kJ/mol 27.0452 ± 0.0016 67624-57-1*0 Ethynylium [CCH]+ (g) 1687.64 1690.98 ± 0.15 kJ/mol 25.0288 ± 0.0016 16456-59-0*0 Methylamidogen anion [CH3NH]- (g) 145.41 134.58 ± 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 Bromanylium Br+ (g) 1257.786 1251.723 ± 0.056 kJ/mol 79.90345 ± 0.00100 22541-56-6*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) 475.05 467.03 ± 0.84 kJ/mol 40.0639 ± 0.0024 2143-70-6*1 Propargylium [CH2CCH]+ (g) 1193.56 1190.74 ± 0.32 kJ/mol 39.0554 ± 0.0024 21540-27-2*0 Cycloprop-1-enyl CH2(CHC) (g) 527.50 523.11 ± 0.58 kJ/mol 39.0559 ± 0.0024 19528-44-0*0 Cyclopropenylidene C(CHCH) (g) 497.10 496.13 ± 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) 1598.50 1602.88 ± 0.90 kJ/mol 37.0395 ± 0.0024 75104-46-0*0 sec-Butyl CH3CH2CHCH3 (g) 91.35 66.58 ± 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) 327.18 317.18 ± 0.75 kJ/mol 53.0825 ± 0.0032 1204515-52-5*0 n-Heptane CH3(CH2)5CH3 (g) -145.40 -187.27 ± 0.44 kJ/mol 100.2019 ± 0.0057 142-82-5*0 Oxoethanide [CH3CO]- (g) -43.9 -49.5 ± 1.3 kJ/mol 43.0452 ± 0.0016 78944-68-0*0 Iodine cation I+ (g) 1115.549 1115.149 ± 0.0062 kJ/mol 126.903921 ± 0.000030 22541-93-1*0 2-Hydroperoxyethyl CH2CH2OOH (g, gauche-syn) 64.6 50.3 ± 1.3 kJ/mol 61.0599 ± 0.0017 126898-97-3*32 Methoxyoxomethyl CH3OCO (g, anti-staggered) -152.7 -160.8 ± 1.2 kJ/mol 59.0440 ± 0.0017 16481-04-2*1 Hydroxyformyl HOCO (g, cis) -174.34 -177.36 ± 0.48 kJ/mol 45.0174 ± 0.0010 2564-86-5*2 Hydroxyformyl anion [HOCO]- (g, cis) -319.54 -322.12 ± 0.56 kJ/mol 45.0180 ± 0.0010 78944-70-4*2 Water dimer (H2O)2 (g) -491.029 -499.068 ± 0.044 kJ/mol 36.03056 ± 0.00066 25655-83-8*0 Difluoride [F2]- (g) -290.6 -289.8 ± 1.3 kJ/mol 37.9973550 ± 0.0000010 12184-85-9*0 Ethyl formate HC(O)OCH2CH3 (g, syn) -375.0 -393.8 ± 1.0 kJ/mol 74.0785 ± 0.0025 109-94-4*1 Propionic acid CH3CH2C(O)OH (g, syn) -435.91 -453.80 ± 0.60 kJ/mol 74.0785 ± 0.0025 79-09-4*1 (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) 652.7 649.7 ± 1.3 kJ/mol 41.03212 ± 0.00082 20813-32-5*22 Diazomethanide [HCNN]- (g, singlet) 305.19 302.09 ± 0.76 kJ/mol 41.03267 ± 0.00082 100840-43-5*2 Isocyanoamidogen HNNC (g, c-quartet) 828.2 825.4 ± 1.3 kJ/mol 41.03212 ± 0.00082 947408-73-3*22 Ethylamidogen anion [CH3CH2NH]- (g) 106.54 88.88 ± 0.80 kJ/mol 44.0763 ± 0.0017 54448-40-7*0 Chloromethide [CH2Cl]- (g) 56.3 53.0 ± 2.0 kJ/mol 49.4798 ± 0.0012 60291-29-4*0 Hexachloroethane CCl3CCl3 (g) -144.2 -146.6 ± 1.3 kJ/mol 236.7376 ± 0.0056 67-72-1*0 cis-1,2-Dichloroethene CHClCHCl (g, cis) 3.80 -2.19 ± 0.55 kJ/mol 96.9427 ± 0.0024 156-59-2*0 Dichloroacetylene ClCCCl (g) 232.71 236.02 ± 0.74 kJ/mol 94.9268 ± 0.0024 7572-29-4*0 Difluoromethylene CF2 (g) -193.87 -193.40 ± 0.35 kJ/mol 50.00751 ± 0.00080 2154-59-8*0 1,1-Difluoroethane CH3CHF2 (g) -489.06 -502.78 ± 0.53 kJ/mol 66.0500 ± 0.0016 75-37-6*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) 141.95 123.04 ± 0.40 kJ/mol 91.1310 ± 0.0056 18860-15-6*0 Norbornadiene (CHCH)(CHCH2CH)(CHCH) (g) 264.8 239.4 ± 1.5 kJ/mol 92.1384 ± 0.0056 121-46-0*0 Benzonitrile C6H5CN (g) 229.98 215.79 ± 0.92 kJ/mol 103.1213 ± 0.0056 100-47-0*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) -187.53 -201.09 ± 0.93 kJ/mol 57.0717 ± 0.0024 24262-31-5*0 Methyl nitrite CH3ONO (g) -55.42 -66.09 ± 0.43 kJ/mol 61.0401 ± 0.0010 624-91-9*0 Acryloyl CH2CHCO (g, 2A") 102.80 97.20 ± 0.98 kJ/mol 55.0553 ± 0.0024 72241-20-4*2 3-Oxo-1,2-propadien-1-yl HCCCO (g) 290.35 292.86 ± 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) 388.6 386.7 ± 1.1 kJ/mol 51.0672 ± 0.0032 102275-54-7*0 2-Hydrotrioxy OO(H)O (g) 299.4 293.7 ± 1.2 kJ/mol 49.00614 ± 0.00090 *12500-78-6*0 Difluorosilylene SiF2 (g, singlet) -629.3 -630.1 ± 1.3 kJ/mol 66.08231 ± 0.00030 13966-66-0*2 Silylene SiH2 (g, triplet) 361.94 360.32 ± 0.99 kJ/mol 30.10138 ± 0.00033 13825-90-6*1 Di-mu-hydrodihydrodisilicon HSi(HSiHH) (g, trans-singlet) 374.7 364.3 ± 2.3 kJ/mol 60.20276 ± 0.00066 129970-82-7*12 Chloric acid HOCl(O)O (g) 0.6 -6.5 ± 1.1 kJ/mol 84.4588 ± 0.0013 7790-93-4*0 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) 431.6 421.2 ± 1.2 kJ/mol 78.1118 ± 0.0048 628-16-0*0 1,3-Pentadiyne HCCCCCH3 (g) 418.13 413.91 ± 0.72 kJ/mol 64.0853 ± 0.0040 4911-55-1*0 2-Methylallyl CH3C(CH2)CH2 (g) 155.96 138.84 ± 0.77 kJ/mol 55.0984 ± 0.0032 15157-95-6*0 3-Butenyl CH2CHCH2CH2 (g) 223.25 206.75 ± 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) 232.02 203.21 ± 0.75 kJ/mol 178.2292 ± 0.0112 85-01-8*0 Disulfene oxide SSO (g) -50.62 -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) -28.75 -45.57 ± 0.38 kJ/mol 62.1350 ± 0.0062 75-08-1*0 Dinitrogen tetraoxide O2NNO2 (g) 20.17 10.88 ± 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 Trioxygen difluoride FOOOF (g, trans) 112.5 106.7 ± 1.1 kJ/mol 85.99501 ± 0.00090 16829-28-0*1 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 Oxygen atom O (g, singlet) 436.665 438.523 ± 0.0021 kJ/mol 15.99940 ± 0.00030 17778-80-2*2 Methyliumylidene [CH]+ (g) 1619.757 1623.100 ± 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 Methanol cation [CH3OH]+ (g) 856.95 846.62 ± 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 Carbonic acid C(O)(OH)2 (g, cis-trans) -596.48 -606.59 ± 0.74 kJ/mol 62.0248 ± 0.0012 463-79-6*2 Carbonic acid C(O)(OH)2 (g, trans-trans) -561.30 -570.14 ± 0.91 kJ/mol 62.0248 ± 0.0012 463-79-6*3 Bromochlorane BrCl (g) 21.891 14.447 ± 0.059 kJ/mol 115.3567 ± 0.0013 13863-41-7*0 Hydroperoxycarbonyl HOOCO (g) -73.25 -77.11 ± 0.97 kJ/mol 61.0168 ± 0.0012 153751-35-0*0 Iodine monobromide IBr (g) 49.727 40.780 ± 0.066 kJ/mol 206.8085 ± 0.0010 7789-33-5*0 Allylium [CH2CHCH2]+ (g) 964.48 952.92 ± 0.33 kJ/mol 41.0713 ± 0.0024 1724-44-3*0 Propylidyne CH3CH2C (g, quartet) 624.9 613.3 ± 1.3 kJ/mol 41.0718 ± 0.0024 85056-54-8*2 1-Propynyl CH3CC (g) 528.56 526.39 ± 0.65 kJ/mol 39.0559 ± 0.0024 89342-91-6*0 1-Propynylide [CH3CC]- (g) 264.62 261.03 ± 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 t-Butyl anion [(CH3)3C]- (g) 76.9 52.1 ± 1.3 kJ/mol 57.1148 ± 0.0033 65114-21-8*0 Tetroxidane HOOOOH (g, C1) -33.33 -43.99 ± 0.44 kJ/mol 66.0135 ± 0.0012 29683-94-1*21 5-Ethenyl-1,3-cyclopentadiene CH2CHCH(CHCHCHCH) (g, perp) 237.0 215.3 ± 1.4 kJ/mol 92.1384 ± 0.0056 29647-85-6*1 Hydrogen fluoride HF (aq, 5500 H2O) -324.55 ± 0.13 kJ/mol 20.006343 ± 0.000070 7664-39-3*955 2-Hydroxyethenyl CHCHOH (g, trans-cis) 137.99 131.25 ± 0.72 kJ/mol 43.0446 ± 0.0016 108665-16-3*21 Oxiranylidene CH2(CO) (g, singlet) 213.5 209.3 ± 1.4 kJ/mol 42.0367 ± 0.0016 50983-85-2*2 Iodine I (g, 2P3/2) 107.157 106.757 ± 0.0021 kJ/mol 126.904470 ± 0.000030 14362-44-8*1 1-Hydroperoxyethylium [CH3CHOOH]+ (g, trans singlet) 690.5 674.8 ± 1.5 kJ/mol 61.0594 ± 0.0017 *126898-98-4*21 Oxidanylium [OH]+ (g) 1293.362 1293.391 ± 0.026 kJ/mol 17.00679 ± 0.00031 12259-29-9*0 Hydroxyformyl anion [HOCO]- (g, trans) -313.64 -315.45 ± 0.56 kJ/mol 45.0180 ± 0.0010 78944-70-4*1 Ethoxyethene CH2CHOCH2CH3 (g, cis-trans) -117.8 -141.6 ± 1.5 kJ/mol 72.1057 ± 0.0033 109-92-2*2 1,1-Ethenediol CH2C(OH)2 (g, syn-anti Cs) -307.56 -320.51 ± 0.83 kJ/mol 60.0520 ± 0.0017 10375-04-9*1 1,2-Ethenediol HOCHCHOH (g, cis) -272.68 -285.01 ± 0.90 kJ/mol 60.0520 ± 0.0017 1571-60-4*1 (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 ± 0.98 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) 319.8 309.7 ± 1.3 kJ/mol 42.0599 ± 0.0016 176964-54-8*2 Bromotrichloromethane CCl3Br (g) -29.94 -39.09 ± 0.54 kJ/mol 198.2728 ± 0.0030 75-62-7*0 Dichloromethyl CHCl2 (g) 92.87 90.95 ± 0.88 kJ/mol 83.9240 ± 0.0020 3474-12-2*0 Chloromethyl CH2Cl (g) 118.45 115.38 ± 0.87 kJ/mol 49.4793 ± 0.0012 6806-86-6*0 Methyl hypochlorite CH3OCl (g) -53.0 -62.9 ± 1.4 kJ/mol 66.4866 ± 0.0013 593-78-2*0 1,2-Dichloroethane CH2ClCH2Cl (g) -118.50 -130.44 ± 0.53 kJ/mol 98.9586 ± 0.0024 107-06-2*0 Tetraiodomethane CI4 (g) 320.8 315.7 ± 2.0 kJ/mol 519.62858 ± 0.00081 507-25-5*0 Chlorofluoromethane CH2FCl (g) -256.44 -263.64 ± 0.85 kJ/mol 68.4777 ± 0.0012 593-70-4*0 Difluoromethyliumyl [CF2]+ (g) 908.24 908.66 ± 0.77 kJ/mol 50.00696 ± 0.00080 54250-40-7*0 Fluoromethyliumylidene [CF]+ (g) 1123.02 1126.24 ± 0.44 kJ/mol 31.00855 ± 0.00080 33412-11-2*0 1,2-Difluoroacetylene FCCF (g) 2.85 5.68 ± 0.63 kJ/mol 62.0182 ± 0.0016 689-99-6*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) 413.88 404.78 ± 0.95 kJ/mol 76.0965 ± 0.0048 100569-88-8*0 Cycloheptene CH2(CHCHCH2CH2CH2CH2) (g) 28.54 -8.69 ± 0.74 kJ/mol 96.1702 ± 0.0057 628-92-2*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) 791.96 776.93 ± 0.39 kJ/mol 96.1018 ± 0.0048 34468-25-2*0 Nitrosobenzene C6H5NO (g) 216.9 199.9 ± 1.2 kJ/mol 107.1100 ± 0.0048 586-96-9*0 1-Methylethoxy CH3CH(O)CH3 (g) -25.06 -43.83 ± 0.74 kJ/mol 59.0871 ± 0.0025 3958-66-5*0 Nitromethyl CH2N(O)O (g) 139.6 130.2 ± 1.1 kJ/mol 60.0321 ± 0.0010 16787-85-2*0 2-Butanone CH3CH2C(O)CH3 (g) -216.84 -238.30 ± 0.79 kJ/mol 72.1057 ± 0.0033 78-93-3*0 Dioxaziridinyl N(OO) (g) 355.1 352.6 ± 1.4 kJ/mol 46.00554 ± 0.00060 66252-29-7*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 Trioxidanyl HOOO (g, trans) 25.36 23.37 ± 0.13 kJ/mol 49.00614 ± 0.00090 12500-78-6*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) 134.0 111.0 ± 1.4 kJ/mol 80.1277 ± 0.0048 96-38-8*0 Trifluorosilyl SiF3 (g) -993.1 -996.1 ± 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 Hypochloroperoxoous acid, hydroxy ester HOOOCl (g, syn) 48.4 41.5 ± 1.8 kJ/mol 84.4588 ± 0.0013 928652-99-7*1 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) 424.7 414.8 ± 1.3 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 ± 1.6 kJ/mol 78.1118 ± 0.0048 177856-38-1*0 1-Aminoethyl CH3CHNH2 (g) 133.35 116.57 ± 0.94 kJ/mol 44.0758 ± 0.0017 30208-36-7*0 Ethylamidogen CH3CH2NH (g) 166.73 150.61 ± 0.95 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) 85.84 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) 54.462 52.560 ± 0.067 kJ/mol 65.45884 ± 0.00095 2696-92-6*0 Carbide [C2]- (g) 504.41 510.98 ± 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) 1047.17 1054.76 ± 0.68 kJ/mol 48.0428 ± 0.0032 12184-80-4*0 Methane cation [CH4]+ (g) 1150.688 1144.305 ± 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 Iodide I- (aq) -56.827 ± 0.090 kJ/mol 126.905019 ± 0.000030 20461-54-5*800 Acetylene cation [HCCH]+ (g) 1328.90 1328.24 ± 0.12 kJ/mol 26.0367 ± 0.0016 25641-79-6*0 Hydrogen bromide HBr (aq) -120.50 ± 0.13 kJ/mol 80.9119 ± 0.0010 10035-10-6*800 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 Bromonium [HBrH]+ (g) 924.4 913.6 ± 3.0 kJ/mol 81.9193 ± 0.0010 36658-54-5*0 Isocyanomethyl CH2NC (g) 363.3 360.8 ± 1.1 kJ/mol 40.0440 ± 0.0016 70971-59-4*0 Methyloxoniumylidene [CH3O]+ (g) 1062.74 1054.93 ± 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) -105.381 -109.221 ± 0.095 kJ/mol 30.02598 ± 0.00087 50-00-0*2 Hydroxymethylene HCOH (g, cis) 131.12 127.38 ± 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) -360.36 -366.44 ± 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 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) 280.28 269.45 ± 0.76 kJ/mol 41.0718 ± 0.0024 6067-68-1*1 Dinitrogen pentoxide O2NONO2 (g) 24.32 14.75 ± 0.29 kJ/mol 108.0105 ± 0.0015 10102-03-1*0 Cyclopropynyl CH(CC) (g) 711.28 715.41 ± 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 Bromo hypobromite BrOBr (g) 121.1 104.6 ± 1.2 kJ/mol 175.8074 ± 0.0020 21308-80-5*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 n-Hexane CH3CH2CH2CH2CH2CH3 (cr,l) -179.83 -198.49 ± 0.32 kJ/mol 86.1754 ± 0.0049 110-54-3*500 Bromide Br- (aq) -120.50 ± 0.13 kJ/mol 79.90455 ± 0.00100 24959-67-9*800 n-Nonane CH3(CH2)7CH3 (g) -176.27 -228.06 ± 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) -10.85 -23.48 ± 0.93 kJ/mol 45.0605 ± 0.0017 4422-54-2*2 Ethoxy CH3CH2O (g) 1.36 -12.07 ± 0.42 kJ/mol 45.0605 ± 0.0017 2154-50-9*0 Vinyl alcohol cation [CH2CHOH]+ (g, anti) 778.6 767.4 ± 1.3 kJ/mol 44.0520 ± 0.0017 57239-63-1*2 1-Hydroxyethylidene CH3COH (g, syn singlet) 70.06 59.55 ± 0.86 kJ/mol 44.0526 ± 0.0017 30967-49-8*22 1-Hydroxyethenyl CH2COH (g) 121.33 114.95 ± 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) 721.9 726.3 ± 1.6 kJ/mol 40.0208 ± 0.0016 *12071-23-7*2 Dioxidenium [HOO]+ (g) 1110.87 1107.98 ± 0.11 kJ/mol 33.00619 ± 0.00060 12207-52-2*0 Oxoethylidene HCC(O)H (g, singlet) 275.4 272.6 ± 1.7 kJ/mol 42.0367 ± 0.0016 39920-84-8*2 Hydrogen difluoride (F)(HF) (g, lin) -198.5 -198.4 ± 1.2 kJ/mol 39.004746 ± 0.000070 12528-21-1*1 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) 39.5 25.9 ± 1.3 kJ/mol 61.0599 ± 0.0017 126898-98-4*0 Formic acid cation [HC(O)OH]+ (g, syn) 721.95 714.86 ± 0.25 kJ/mol 46.0248 ± 0.0010 50614-05-6*1 Formyloxidanyl HC(O)O (g, 2B2) -121.98 -125.33 ± 0.55 kJ/mol 45.0174 ± 0.0010 16499-21-1*2 1-Methoxyethenol CH2C(OH)OCH3 (g, anti-syn) -284.2 -303.6 ± 1.2 kJ/mol 74.0785 ± 0.0025 4453-91-2*1 1-Propene-1,2-diol CH3C(OH)CHOH (g, cis) -311.4 -329.8 ± 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 ± 1.3 kJ/mol 74.0785 ± 0.0025 7333-03-1*2 (Formyloxy)methyl HC(O)OCH2 (g, anti) -135.7 -143.9 ± 1.3 kJ/mol 59.0440 ± 0.0017 3122-12-1*2 Water anion [(H)(OH)]- (g, vdW ?) 31.3 29.8 ± 3.1 kJ/mol 18.01583 ± 0.00033 12259-30-2*100 Carboxymethyl CH2C(O)OH (g, anti) -206.0 -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 Trioxidanylium [HOOO]+ (g, trans) 1070.7 1064.4 ± 1.4 kJ/mol 49.00559 ± 0.00090 74241-49-9*1 Ethylideneamidogen CH3CHN (g) 209.8 199.3 ± 1.1 kJ/mol 42.0599 ± 0.0016 28445-33-2*0 Chlorine difluoride FClF (g) -47.0 -48.2 ± 1.3 kJ/mol 73.44951 ± 0.00090 24801-48-7*0 (Methyleneamino)methyl CH2NCH2 (g) 244.3 233.6 ± 1.3 kJ/mol 42.0599 ± 0.0016 56391-78-7*0 2-Aminoethenyl CHCHNH2 (g, syn) 325.6 315.4 ± 1.3 kJ/mol 42.0599 ± 0.0016 176964-54-8*1 2-Aziridinyl NH(CHCH2) (g, syn) 361.0 348.8 ± 1.7 kJ/mol 42.0599 ± 0.0016 *23838-09-7*1 Azide [NNN]- (g) 193.63 190.13 ± 0.91 kJ/mol 42.02077 ± 0.00021 14343-69-2*0 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-Diazirene CH(NHN) (g) 405.1 398.1 ± 1.4 kJ/mol 42.04006 ± 0.00082 157-23-3*0 1H-Triazirin-1-yl N(NN) (g) 586.0 584.2 ± 2.0 kJ/mol 42.02022 ± 0.00021 912535-95-6*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) 28.8 27.0 ± 1.3 kJ/mol 201.2849 ± 0.0048 7094-17-9*0 Iodomethane CH3I (l) -12.26 ± 0.20 kJ/mol 141.93899 ± 0.00083 74-88-4*590 Difluoromethylene CF2 (g, triplet) 43.32 44.04 ± 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) -302.99 -309.75 ± 0.83 kJ/mol 64.0341 ± 0.0016 1630-77-9*0 Fluoroethynyl CCF (g) 445.3 449.8 ± 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) 1003.1 1010.6 ± 2.3 kJ/mol 73.0721 ± 0.0048 88053-50-3*0 Benzene C6H6 (cr,l) 50.81 49.26 ± 0.21 kJ/mol 78.1118 ± 0.0048 71-43-2*500 o-Benzyne C6H4 (g) 468.26 459.34 ± 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) -72.43 -117.92 ± 0.52 kJ/mol 98.1861 ± 0.0057 291-64-5*0 Bifluoride [(HF)(F)]- (g, singlet) -481.8 -480.6 ± 1.9 kJ/mol 39.005295 ± 0.000070 *18130-74-0*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) 164.0 160.0 ± 1.1 kJ/mol 54.0474 ± 0.0024 2961-80-0*0 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) 285.33 278.83 ± 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 Chloryl hydride HCl(O)O (g) 197.7 191.2 ± 1.6 kJ/mol 68.4594 ± 0.0011 174365-32-3*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) 404.4 386.7 ± 1.2 kJ/mol 78.1118 ± 0.0048 659-85-8*0 Hydrogen fluoride HF (aq) -334.67 ± 0.15 kJ/mol 20.006343 ± 0.000070 7664-39-3*800 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 2-Naphthalenyl C6H4(CHCCHCH) (g) 416.8 397.3 ± 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 86.81 ± 0.72 kJ/mol 93.1265 ± 0.0048 62-53-3*0 Pyruvic acid CH3C(O)C(O)OH (g) -521.1 -535.4 ± 1.1 kJ/mol 88.0621 ± 0.0026 127-17-3*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 Peroxynitrous acid HOONO (g, cis, perp) -0.12 -7.17 ± 0.53 kJ/mol 63.01288 ± 0.00091 14691-52-2*2 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 Nitrosodioxaziridine ONN(OO) (g, trans) 413.7 407.6 ± 1.8 kJ/mol 76.01168 ± 0.00091 132871-99-9*1 Perchloric acid HOCl(O)(O)O (g) 11.7 0.2 ± 1.3 kJ/mol 100.4582 ± 0.0015 7601-90-3*0 2-Hydrotrioxy cation [OO(H)O]+ (g) 1298.4 1291.8 ± 1.4 kJ/mol 49.00559 ± 0.00090 *74241-49-9*0 Deuterium atom D (g) 219.804 221.717 ± 0.000 kJ/mol 2.01410177800 ± 0.00000000040 16873-17-9*0 Triiodide [I3]- (aq) -51.53 ± 0.79 kJ/mol 380.713959 ± 0.000090 14900-04-0*800 Methylammonium [CH3NH3]+ (g) 628.39 609.48 ± 0.97 kJ/mol 32.06453 ± 0.00091 17000-00-9*0 Aminomethylene CHNH2 (g) 245.9 238.1 ± 1.5 kJ/mol 29.04126 ± 0.00083 35430-17-2*0 Methyleneamidogen anion [CH2N]- (g) 192.85 189.10 ± 0.88 kJ/mol 28.03387 ± 0.00082 28892-56-0*0 (Z)-Iminomethyl HCNH (g, cis) 294.54 291.05 ± 0.89 kJ/mol 28.03332 ± 0.00082 54980-11-9*0 Aminomethylidyne CNH2 (g) 372.0 368.4 ± 1.1 kJ/mol 28.03332 ± 0.00082 84654-89-7*0 2-Hydrotrioxy anion [OO(H)O]- (g) 27.4 21.6 ± 1.4 kJ/mol 49.00669 ± 0.00090 *89965-38-8*0 Ethynylamidogen HCCNH (g) 395.31 393.28 ± 0.96 kJ/mol 40.0440 ± 0.0016 73456-14-1*0 Methyleneoxonium CH2OH2 (g) 152.54 144.22 ± 0.49 kJ/mol 32.04186 ± 0.00090 177788-17-9*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) -602.30 -611.61 ± 0.58 kJ/mol 62.0248 ± 0.0012 463-79-6*0 Oxygen cation monohydrate [(HOH)O]+ (g) 1153.4 1147.9 ± 3.3 kJ/mol 34.01413 ± 0.00062 *31748-17-1*0 Peroxyformic acid HC(O)OOH (g, trans) -265.3 -273.2 ± 1.5 kJ/mol 62.0248 ± 0.0012 107-32-4*2 1,3-Propanediyl CH2CH2CH2 (g, triplet Cs) 319.3 307.1 ± 1.3 kJ/mol 42.0797 ± 0.0024 32458-33-6*11 Propan-1-yl-3-ylidene CH2CH2CH (g, quartet) 554.4 545.7 ± 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 Cycloprop-2-enyl CH(CHCH) (g) 490.33 485.78 ± 0.58 kJ/mol 39.0559 ± 0.0024 28933-84-8*0 2-Propen-1-yl-3-ylidene CH2CHC (g) 556.67 554.40 ± 0.89 kJ/mol 39.0559 ± 0.0024 202744-74-9*0 2-Propynylidyne anion [CCCH]- (g) 540.81 545.58 ± 0.75 kJ/mol 37.0406 ± 0.0024 82893-67-2*0 t-Butylium [(CH3)3C]+ (g) 733.97 710.69 ± 0.98 kJ/mol 57.1137 ± 0.0033 14804-25-2*0 Chlorine fluoride cation [ClF]+ (g) 1165.52 1165.70 ± 0.49 kJ/mol 54.45055 ± 0.00090 12432-44-9*0 Methylcyclopropane CH3CH(CH2CH2) (g) 47.9 24.6 ± 1.3 kJ/mol 56.1063 ± 0.0032 594-11-6*0 1,2-Butadienylium [CH3CHCCH]+ (g, singlet) 1099.2 1089.9 ± 1.2 kJ/mol 53.0820 ± 0.0032 *65114-67-2*2 Dihydrogen fluoride anion [HFH]- (g, triplet) 133.2 131.9 ± 1.6 kJ/mol 21.01483 ± 0.00014 117339-92-1*1 2-Hydroxy-1,1-dimethylethyl (CH3)2CCH2OH (g) -71.6 -96.5 ± 1.4 kJ/mol 73.1137 ± 0.0033 5723-75-1*0 Oxygen anion monohydrate [(HOH)O]- (g) -238.9 -244.2 ± 3.0 kJ/mol 34.01523 ± 0.00062 31748-17-1*0 Vinylcyclopentadienyl CH2CHC(CHCHCHCH) (g) 314.8 296.8 ± 1.7 kJ/mol 91.1305 ± 0.0056 1201826-88-1*0 2,2-Dimethylbutane CH3CH2C(CH3)3 (g) -145.28 -185.71 ± 0.75 kJ/mol 86.1754 ± 0.0049 75-83-2*0 n-Decane CH3(CH2)8CH3 (g) -192.30 -249.04 ± 0.75 kJ/mol 142.2817 ± 0.0081 124-18-5*0 Ethanol CH3CH2OH (cr,l) -269.61 -277.37 ± 0.20 kJ/mol 46.0684 ± 0.0017 64-17-5*500 Vinyl alcohol cation [CH2CHOH]+ (g, syn) 786.63 775.41 ± 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) -152.98 -160.03 ± 0.56 kJ/mol 43.0452 ± 0.0016 35731-40-9*0 (E)-Diazene cation [HNNH]+ (g, trans) 1132.53 1125.59 ± 0.64 kJ/mol 30.02881 ± 0.00020 59952-06-6*0 1-Hydroxyethenylium [CH2COH]+ (g, singlet) 841.8 834.9 ± 1.4 kJ/mol 43.0441 ± 0.0016 41084-89-3*2 Oxywater (H2O)O (g) 64.9 58.4 ± 1.3 kJ/mol 34.01468 ± 0.00062 171363-09-0*0 Oxiranyl anion [CH2(CHO)]- (g, singlet) 121.3 113.3 ± 1.5 kJ/mol 43.0452 ± 0.0016 72722-59-9*2 Fluorohydrochlorine cation [FClH]+ (g) 975.3 972.3 ± 2.0 kJ/mol 55.45849 ± 0.00090 70110-64-4*0 COC vdW (CO)(C) (g, triplet) 589.8 598.5 ± 1.5 kJ/mol 40.0208 ± 0.0016 *12071-24-8*1 (Z)-Diazene HNNH (g, cis) 228.80 221.67 ± 0.59 kJ/mol 30.02936 ± 0.00020 15626-42-3*0 Oxirene O(CHCH) (g, c-triplet) 389.7 385.6 ± 1.4 kJ/mol 42.0367 ± 0.0016 157-18-6*12 1,2,3-Trioxolane O(OCH2CH2O) (g) -9.4 -27.1 ± 1.8 kJ/mol 76.0514 ± 0.0019 6669-36-9*0 Methanediol CH2(OH)2 (g, Cs gauche) -368.86 -381.80 ± 0.73 kJ/mol 48.0413 ± 0.0010 463-57-0*2 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) 923.8 911.4 ± 1.5 kJ/mol 61.0594 ± 0.0017 268728-77-4*1 Ethaneperoxolate [CH3CH2OO]- (g, gauche) -120.47 -137.09 ± 0.72 kJ/mol 61.0604 ± 0.0017 268728-75-2*3 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 Trioxidaniumyl [HOOOH]+ (g, t, t) 925.5 916.3 ± 1.4 kJ/mol 50.01353 ± 0.00091 161321-37-5*2 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) -295.4 -314.9 ± 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) -200.2 -213.9 ± 1.5 kJ/mol 73.0706 ± 0.0025 2887-49-2*1 Glyoxal OCHCHO (g) -207.82 -213.38 ± 0.55 kJ/mol 58.0361 ± 0.0017 107-22-2*0 Hydrogen difluoride cation [FFH]+ (g) 1174.3 1171.3 ± 1.5 kJ/mol 39.004198 ± 0.000070 *126950-54-7*0 Hydroxyaminiumyl [NOH]+ (g) 1161.1 1158.2 ± 1.4 kJ/mol 31.01353 ± 0.00032 63559-88-6*0 Dimethylmethyleneammonium [(CH3)2NCH2]+ (g) 697.1 672.1 ± 1.3 kJ/mol 58.1018 ± 0.0025 28149-27-1*0 Chlorine difluoride cation [FClF]+ (g) 998.9 996.7 ± 1.7 kJ/mol 73.44896 ± 0.00090 32629-46-2*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 Trichloromethide [CCl3]- (g) -123.2 -122.7 ± 2.0 kJ/mol 118.3693 ± 0.0028 14478-07-0*0 Chlorine chlorite ClOClO (g, gauche) 168.6 166.2 ± 1.3 kJ/mol 102.9042 ± 0.0019 105206-44-8*3 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) -172.9 -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) -48.8 ± 1.5 kJ/mol 131.3874 ± 0.0031 79-01-6*590 Tetrachloroethene CCl2CCl2 (l) -61.18 ± 0.99 kJ/mol 165.8322 ± 0.0039 127-18-4*500 Fluoride F- (aq) -334.67 ± 0.15 kJ/mol 18.99895178 ± 0.00000050 16984-48-8*800 Trichloroethene CHClCCl2 (g) -10.9 -14.2 ± 1.5 kJ/mol 131.3874 ± 0.0031 79-01-6*0 Bromodichloromethane CHCl2Br (g) -34.9 -46.6 ± 1.2 kJ/mol 163.8280 ± 0.0022 75-27-4*0 Difluorodibromomethane CF2Br2 (g) -360.3 -378.3 ± 1.3 kJ/mol 209.8155 ± 0.0022 75-61-6*0 Dichlorodibromomethane CCl2Br2 (g) 27.7 11.7 ± 1.3 kJ/mol 242.7241 ± 0.0028 594-18-3*0 Difluorobromomethane CHF2Br (g) -411.39 -424.59 ± 0.47 kJ/mol 130.9194 ± 0.0013 1511-62-2*0 Hydroxyamidogen HNOH (g, cis) 123.3 116.7 ± 1.7 kJ/mol 32.02202 ± 0.00034 13940-32-4*2 1,2-Difluoroethane CH2FCH2F (g) -434.43 -447.86 ± 0.80 kJ/mol 66.0500 ± 0.0016 624-72-6*0 Hydroxyaminylium [HNOH]+ (g, trans) 1019.5 1012.3 ± 2.5 kJ/mol 32.02147 ± 0.00034 66097-71-0*1 Fluoro(fluorooxy)methylene FCOF (g, trans) -37.5 -39.1 ± 1.4 kJ/mol 66.00691 ± 0.00085 479587-30-9*1 Chlorosyl hydride HClO (g) 141.9 139.0 ± 1.7 kJ/mol 52.46004 ± 0.00095 71572-35-5*0 Aquachlorine cation [ClOH2]+ (g) 821.9 815.1 ± 1.8 kJ/mol 53.46743 ± 0.00096 142599-65-3*0 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) 929.47 909.97 ± 0.53 kJ/mol 91.1299 ± 0.0056 6711-19-9*0 2,5-Norbornadien-7-yl (CHCH)(CHCHCH)(CHCH) (g) 480.1 459.0 ± 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 Anisole C6H5OCH3 (g) -45.88 -70.73 ± 0.64 kJ/mol 108.1378 ± 0.0056 100-66-3*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) -942.54 -947.54 ± 0.87 kJ/mol 186.0546 ± 0.0048 392-56-3*0 Chlorobenzene cation [C6H5Cl]+ (g) 942.60 928.68 ± 0.61 kJ/mol 112.5561 ± 0.0049 55450-32-3*0 Chlorobenzene C6H5Cl (cr,l) 11.35 ± 0.59 kJ/mol 112.5566 ± 0.0049 108-90-7*500 m-Chlorophenyl C6H4Cl (g) 321.6 310.9 ± 1.6 kJ/mol 111.5487 ± 0.0049 3474-40-6*0 p-Chlorophenyl C6H4Cl (g) 324.5 313.7 ± 1.6 kJ/mol 111.5487 ± 0.0049 2396-00-1*0 o-Chlorophenyl C6H4Cl (g) 328.8 318.1 ± 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) 113.7 113.7 ± 1.1 kJ/mol 204.0084 ± 0.0048 591-50-4*500 Nitrobenzene C6H5N(O)O (g) 82.2 62.2 ± 1.4 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 1,3-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) 30.64 19.21 ± 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 Formaldonitrone CH2NHO (g) 78.4 67.2 ± 1.4 kJ/mol 45.04066 ± 0.00088 67353-84-8*0 Bifluoride [FFH]- (g, triplet) -68.0 -67.6 ± 1.6 kJ/mol 39.005295 ± 0.000070 *18130-74-0*1 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 Vinylvinylidene CH2CHCHC (g, singlet) 494.2 488.9 ± 1.7 kJ/mol 52.0746 ± 0.0032 148759-16-4*2 Dioxosilane SiO2 (cr, quartz) -906.76 -911.74 ± 0.63 kJ/mol 60.08430 ± 0.00067 7631-86-9*505 Dioxyamidogen HNOO (g, cis) 240.5 233.8 ± 1.8 kJ/mol 47.01348 ± 0.00061 71843-95-3*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 Tetrahedryl anion [C(CH(CHCH))]- (g) 634.6 630.7 ± 1.6 kJ/mol 51.0672 ± 0.0032 138805-00-2*0 Silicon carbide SiC (g) 740.4 745.3 ± 2.4 kJ/mol 40.09620 ± 0.00085 409-21-2*0 Silicon carbide SiC (cr, alpha-hex) -70.5 -71.5 ± 1.5 kJ/mol 40.09620 ± 0.00085 409-21-2*501 Trifluorosilylium [SiF3]+ (g) -111.9 -114.8 ± 1.8 kJ/mol 85.08016 ± 0.00030 38192-99-3*0 Silanide [SiH3]- (g) 69.2 63.6 ± 1.3 kJ/mol 31.10987 ± 0.00037 15807-96-2*0 Oxofluoronium [FO]+ (g) 1342.66 1342.61 ± 0.80 kJ/mol 34.99725 ± 0.00030 12763-67-6*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 Hydroxysilyl anion [SiH2OH]- (g, syn) -219.3 -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) 431.4 419.8 ± 1.4 kJ/mol 78.1118 ± 0.0048 33142-15-3*3 Peroxychlorous acid HOOClO (g, syn) 95.4 89.4 ± 2.0 kJ/mol 84.4588 ± 0.0013 177778-92-6*1 Biphenyl C6H5C6H5 (g) 207.0 178.8 ± 1.1 kJ/mol 154.2078 ± 0.0096 92-52-4*0 Diacetylide [CCCCH]- (g) 460.97 466.01 ± 0.96 kJ/mol 49.0513 ± 0.0032 59012-21-4*0 Sulfinyl hydride H2SO (g) -40.7 -47.6 ± 1.2 kJ/mol 50.0813 ± 0.0060 25540-60-7*0 Sulfuric acid OS(O)(OH)2 (aq, 45 H2O) -886.52 ± 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 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 -150.56 ± 0.57 kJ/mol 78.1344 ± 0.0062 67-68-5*0 Carbon disulfide SCS (g) 115.90 116.70 ± 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 Triiodide [I3]- (g) -254.3 -257.5 ± 3.4 kJ/mol 380.713959 ± 0.000090 14900-04-0*0 Vinylidene CCH2 (g, triplet) 610.65 610.36 ± 0.39 kJ/mol 26.0373 ± 0.0016 2143-69-3*1 Iminomethide [HCNH]- (g, trans) 237.4 233.6 ± 1.8 kJ/mol 28.03387 ± 0.00082 90623-30-6*1 Fluoronium [(HF)(H)]+ (g, triplet) 1490.1 1491.4 ± 1.9 kJ/mol 21.01373 ± 0.00014 12206-67-6*1 Dihydrogen fluoride anion [(F)(HH)]- (g, singlet) -257.0 -260.1 ± 1.9 kJ/mol 21.01483 ± 0.00014 *117339-92-1*2 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) -235.15 -238.48 ± 0.14 kJ/mol 32.04186 ± 0.00090 67-56-1*500 Formaldehyde cation [CH2O]+ (g) 944.861 941.240 ± 0.096 kJ/mol 30.02543 ± 0.00087 54288-05-0*0 Fluorosyl fluoride FFO (g, triplet) 192.8 193.3 ± 2.3 kJ/mol 53.99621 ± 0.00030 86825-57-2*1 Isoformyl anion [COH]- (g, triplet) 267.4 268.0 ± 1.6 kJ/mol 29.01859 ± 0.00086 81747-63-9*2 Dibromide [Br2]- (g) -197.0 -211.1 ± 2.3 kJ/mol 159.8085 ± 0.0020 12595-70-9*0 1,3-Propanediyl CH2CH2CH2 (g, singlet Cs TS) 358.7 343.7 ± 1.4 kJ/mol 42.0797 ± 0.0024 32458-33-6*22 Hydrogen chloride HCl (aq) -166.989 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*800 Allene cation [CH2CCH2]+ (g) 1132.27 1125.12 ± 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) 452.74 445.61 ± 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 Dioxygen O2 (g, singlet) 94.410 94.383 ± 0.000 kJ/mol 31.99880 ± 0.00060 7782-44-7*2 Propynylidene HCCCH (g, cis singlet) 597.9 599.6 ± 1.2 kJ/mol 38.0480 ± 0.0024 67152-18-5*3 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 2-Butynylium [CH3CCCH2]+ (g, singlet) 1085.9 1077.6 ± 1.3 kJ/mol 53.0820 ± 0.0032 64235-83-2*2 1-Methylene-2-propenyl anion [CH2CHCCH2]- (g) 256.4 246.5 ± 1.3 kJ/mol 53.0830 ± 0.0032 64480-63-3*0 1,3-Butadienyl anion [CH2CHCHCH]- (g) 265.4 255.0 ± 1.5 kJ/mol 53.0830 ± 0.0032 65114-68-3*0 Fluorochlorate [ClF]- (g) -256.03 -255.43 ± 0.81 kJ/mol 54.45165 ± 0.00090 12272-56-9*0 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) -41.34 -54.81 ± 0.91 kJ/mol 45.0605 ± 0.0017 2348-46-1*2 1-Hydroxyethylium [CH3CHOH]+ (g) 608.88 594.46 ± 0.38 kJ/mol 45.0600 ± 0.0017 18682-96-7*0 Chloride Cl- (aq) -166.989 ± 0.023 kJ/mol 35.45325 ± 0.00090 16887-00-6*800 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) 988.7 975.0 ± 1.5 kJ/mol 45.0600 ± 0.0017 54387-07-4*0 Trifluoromethide [CF3]- (g) -637.6 -639.4 ± 1.8 kJ/mol 69.00646 ± 0.00080 54128-17-5*0 Acetaldehyde cation [CH3CHO]+ (g) 832.11 822.13 ± 0.23 kJ/mol 44.0520 ± 0.0017 36505-03-0*0 1-Hydroxyethylidene CH3COH (g, gauche triplet) 185.0 175.5 ± 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 Diiodide [I2]- (g) -178.13 -180.72 ± 0.48 kJ/mol 253.809489 ± 0.000060 12190-71-5*0 Dihydrogen cation [H2]+ (g) 1488.364 1488.480 ± 0.000 kJ/mol 2.01533 ± 0.00014 12184-90-6*0 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) 141.0 135.0 ± 1.6 kJ/mol 43.0452 ± 0.0016 72722-59-9*1 Acetic acid CH3C(O)OH (aq) -485.10 ± 0.27 kJ/mol 60.0520 ± 0.0017 64-19-7*800 Ketenyl anion [HCCO]- (g) -48.42 -47.49 ± 0.82 kJ/mol 41.0293 ± 0.0016 64066-01-9*0 Dicarbon monoxide anion [CCO]- (g) 154.19 157.83 ± 0.83 kJ/mol 40.0213 ± 0.0016 87191-88-6*0 Dicarbon monoxide CCO (g, singlet) 440.23 444.56 ± 0.83 kJ/mol 40.0208 ± 0.0016 12071-23-7*2 COC vdW (CO)(C) (g, singlet) 726.3 734.6 ± 1.7 kJ/mol 40.0208 ± 0.0016 *12071-24-8*2 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) 95.31 92.83 ± 0.73 kJ/mol 42.0367 ± 0.0016 32038-79-2*0 Ethynol HCCOH (g, gauche triplet) 400.0 397.6 ± 1.9 kJ/mol 42.0367 ± 0.0016 32038-79-2*11 Oxoethylidene HCC(O)H (g, anti-triplet) 265.9 262.6 ± 1.6 kJ/mol 42.0367 ± 0.0016 39920-84-8*11 Chlorosyl chloride ClClO (g) 134.5 133.2 ± 1.4 kJ/mol 86.9048 ± 0.0018 86825-56-1*0 1-Hydroperoxyethylium [CH3CHOOH]+ (g, trans triplet) 841.4 829.3 ± 1.7 kJ/mol 61.0594 ± 0.0017 *126898-98-4*11 Ethenyldioxy CH2CHOO (g, anti) 118.7 109.2 ± 1.3 kJ/mol 59.0440 ± 0.0017 88181-72-0*1 Hydrogen difluoride (F)(HF) (g, perp) -187.4 -187.1 ± 1.6 kJ/mol 39.004746 ± 0.000070 12528-21-1*2 Formic acid cation [HC(O)OH]+ (g, anti) 723.8 716.7 ± 1.2 kJ/mol 46.0248 ± 0.0010 50614-05-6*2 Formic acid anion [HC(O)OH]- (g, syn) -256.2 -262.3 ± 1.8 kJ/mol 46.0259 ± 0.0010 19066-82-1*1 Azanylium [NH2]+ (g) 1266.56 1264.49 ± 0.11 kJ/mol 16.02207 ± 0.00016 15194-15-7*0 Isocyanic acid cation [HNCO]+ (g) 1003.02 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 1,2-Ethenediol HOCHCHOH (g, trans) -253.9 -266.2 ± 1.3 kJ/mol 60.0520 ± 0.0017 1571-60-4*2 Hydrogen fluoride HF (aq, 10 H2O) -321.68 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*815 Acetyl chloride CH3C(O)Cl (l) -272.07 ± 0.39 kJ/mol 78.4973 ± 0.0019 75-36-5*500 Methyl formate HC(O)OCH3 (l) -388.48 ± 0.64 kJ/mol 60.0520 ± 0.0017 107-31-3*500 Ethyl formate HC(O)OCH2CH3 (g, anti) -355.3 -374.5 ± 1.4 kJ/mol 74.0785 ± 0.0025 109-94-4*2 Acetoxy CH3C(O)O (g, 2A") -182.13 -190.95 ± 0.80 kJ/mol 59.0440 ± 0.0017 13799-69-4*1 Diazenide [NNH]- (g, vdW) 175.7 176.7 ± 1.6 kJ/mol 29.02197 ± 0.00016 71004-29-0*100 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 (Acetyloxy)methyl CH3C(O)OCH2 (g, anti) -173.8 -186.9 ± 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 Chlorohydrofluorine cation [ClFH]+ (g) 1000.8 998.1 ± 2.1 kJ/mol 55.45849 ± 0.00090 70110-63-3*0 Ammonium fluoride (NH4)F (cr,l) -452.48 -467.05 ± 0.38 kJ/mol 37.03690 ± 0.00029 12125-01-8*500 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) 1363.1 1360.8 ± 1.3 kJ/mol 41.03157 ± 0.00082 205443-18-1*1 Cyanoamidogen anion [HNCN]- (g) 69.73 66.73 ± 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) 305.19 302.09 ± 0.76 kJ/mol 41.03267 ± 0.00082 100840-43-5*0 2-Methyliumylidynehydrazin-2-ium-1-ide [HNNC]+ (g, singlet) 1544.1 1542.4 ± 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) 728.7 725.7 ± 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) -104.67 -124.08 ± 0.42 kJ/mol 153.8215 ± 0.0037 56-23-5*500 Dioxymethylidyne COO (g) 299.8 301.1 ± 1.7 kJ/mol 44.00950 ± 0.00100 791121-04-5*0 Dichloromethylene anion [CCl2]- (g) 75.97 78.25 ± 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) -40.8 -42.5 ± 2.0 kJ/mol 83.9246 ± 0.0020 32180-91-9*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 Ammonium nitrate (NH4)NO3 (cr,l) -350.20 -365.17 ± 0.18 kJ/mol 80.04344 ± 0.00095 6484-52-2*500 Ammonia NH3 (aq, undissoc) -80.883 ± 0.053 kJ/mol 17.03056 ± 0.00022 7664-41-7*1000 1,2-Dichloroethane CH2ClCH2Cl (cr,l) -165.65 ± 0.56 kJ/mol 98.9586 ± 0.0024 107-06-2*500 1,1-Dichloroethane CH3CHCl2 (cr,l) -163.75 ± 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 -156.5 ± 1.9 kJ/mol 202.2928 ± 0.0048 76-01-7*0 Hydrogen fluoride HF (aq, 20 H2O) -321.83 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*818 Chloroform CHCl3 (l) -130.93 ± 0.43 kJ/mol 119.3767 ± 0.0028 67-66-3*590 Chlorodibromomethane CHClBr2 (g) 21.8 3.0 ± 3.5 kJ/mol 208.2793 ± 0.0023 124-48-1*0 Bromochloromethane CH2ClBr (g) -28.2 -42.3 ± 1.3 kJ/mol 129.3833 ± 0.0016 74-97-5*0 Hydrogen fluoride HF (aq, 30 H2O) -321.89 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*820 Fluoromethylene CHF (g) 148.41 148.70 ± 0.43 kJ/mol 32.01704 ± 0.00080 13453-52-6*0 Dioxygenyl ion monohydrate [(H2O)(O2)]+ (g) 829.1 822.0 ± 2.0 kJ/mol 50.01353 ± 0.00091 11083-61-7*0 Ethyl iodide CH3CH2I (g) 8.71 -7.16 ± 0.48 kJ/mol 155.9656 ± 0.0016 75-03-6*0 1,2-Dibromoacetylene BrCCBr (g) 333.0 322.1 ± 2.3 kJ/mol 183.8294 ± 0.0026 624-61-3*0 Fluoro(fluorooxy)methylene FCOF (g, vdW triplet) -97.5 -95.7 ± 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 Azidonitrene NNNN (g, Cs) 692.1 687.5 ± 1.4 kJ/mol 56.02696 ± 0.00028 147363-92-6*2 Benzene cation [C6H6]+ (g) 992.61 976.14 ± 0.21 kJ/mol 78.1113 ± 0.0048 34504-50-2*0 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 Nitrous acid HONO (g, cis) -71.37 -77.73 ± 0.26 kJ/mol 47.01348 ± 0.00061 7782-77-6*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 3-Methylphenyl C6H4CH3 (g, meta) 324.3 306.3 ± 1.2 kJ/mol 91.1305 ± 0.0056 3474-41-7*0 2-Methylphenyl C6H4CH3 (g, ortho) 324.4 306.4 ± 1.2 kJ/mol 91.1305 ± 0.0056 22904-44-5*0 4-Methylphenyl C6H4CH3 (g, para) 327.1 309.1 ± 1.2 kJ/mol 91.1305 ± 0.0056 2396-02-3*0 Benzoic acid C6H5C(O)OH (cr,l) -367.33 -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 -93.8 ± 2.4 kJ/mol 134.1751 ± 0.0072 5779-93-1*0 (2,3-dimethylphenyl)oxomethyl CH3C6H3(CH3)CO (g, ortho-meta) 83.2 60.5 ± 2.6 kJ/mol 133.1672 ± 0.0072 *104680-89-9*0 1,3-Butadiyne-1,4-diyl CCCC (g) 1052.27 1062.24 ± 0.64 kJ/mol 48.0428 ± 0.0032 78015-07-3*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) 158.6 148.7 ± 1.5 kJ/mol 111.5492 ± 0.0049 72863-53-7*0 2-Oxopropylium [CH3C(O)CH2]+ (g) 784.8 771.0 ± 1.7 kJ/mol 57.0707 ± 0.0024 54088-52-7*0 Nitronium [ONO]+ (g) 961.79 958.23 ± 0.20 kJ/mol 46.00499 ± 0.00060 14522-82-8*0 2,3-Butanedione CH3C(O)C(O)CH3 (g) -310.68 -327.24 ± 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 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) 344.0 334.1 ± 1.8 kJ/mol 56.0633 ± 0.0024 2835-41-8*11 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) 250.1 244.0 ± 1.8 kJ/mol 44.03272 ± 0.00087 206442-92-4*1 Trihydrogen dioxide anion [HOHOH]- (g) -487.4 -495.7 ± 1.1 kJ/mol 35.02317 ± 0.00064 12501-19-8*0 1-Isocyanoethylidene CH3CNC (g, triplet) 545.6 540.8 ± 1.6 kJ/mol 53.0627 ± 0.0024 *498544-34-6*1 Peroxyimidogen NOO (g) 405.4 403.4 ± 1.9 kJ/mol 46.00554 ± 0.00060 *60488-31-5*0 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 2-Cyanovinylium [CHCHCN]+ (g, anti triplet) 1517.3 1515.2 ± 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) 1221.9 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 Peroxychlorite [OClOO]- (g) -34.4 -34.4 ± 2.0 kJ/mol 83.4514 ± 0.0013 852472-63-0*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 Hydroxydioxonitrate [HON(O)O]- (g) -193.2 -197.5 ± 2.4 kJ/mol 63.01343 ± 0.00091 58875-09-5*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) 1236.84 1240.97 ± 0.56 kJ/mol 28.08495 ± 0.00030 14067-07-3*0 Disilicon Si2 (g) 587.4 591.3 ± 1.6 kJ/mol 56.17100 ± 0.00060 12597-35-2*0 1-Chloro ozone ClOOO (g, cis vdW) 226.3 223.0 ± 2.3 kJ/mol 83.4509 ± 0.0013 141801-66-3*101 Fluorosilyliumylidene [SiF]+ (g) 648.1 649.3 ± 1.7 kJ/mol 47.08335 ± 0.00030 12518-09-1*0 Oxadiazirene O(NN) (g) 351.7 349.9 ± 1.7 kJ/mol 44.01288 ± 0.00033 227934-45-4*0 Disiloxane SiH3OSiH3 (g) -330.3 -347.4 ± 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 Oxochloronium [ClO]+ (g) 1150.86 1150.70 ± 0.66 kJ/mol 51.45155 ± 0.00095 12301-79-0*0 NON NON (g) 545.5 542.6 ± 1.7 kJ/mol 44.01288 ± 0.00033 227934-46-5*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) 302.6 290.4 ± 1.4 kJ/mol 66.1011 ± 0.0040 62018-46-6*0 (Z)-1-Methylallyl CH3CHCHCH2 (g, cis) 154.74 137.35 ± 0.99 kJ/mol 55.0984 ± 0.0032 98705-00-1*0 Ethylene cation [CH2CH2]+ (g) 1075.22 1068.01 ± 0.11 kJ/mol 28.0526 ± 0.0016 34470-02-5*0 Anthracene C6H4(CH(CC(C4H4)CH)) (g) 256.05 227.03 ± 0.92 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 Hydrosulfide [SH]- (g) -80.53 -80.53 ± 0.18 kJ/mol 33.0745 ± 0.0060 15035-72-0*0 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 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 -64.72 ± 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 Sulfuryl dichloride OS(O)Cl2 (g) -348.06 -354.22 ± 0.75 kJ/mol 134.9702 ± 0.0063 7791-25-5*0 Propylidene CH3CH2CH (g, singlet TS anti) 355.7 340.4 ± 2.0 kJ/mol 42.0797 ± 0.0024 6700-78-3*21 Hydrogen peroxide cation [HOOH]+ (g, cis) 931.06 924.20 ± 0.98 kJ/mol 34.01413 ± 0.00062 12325-10-9*2 Bromine dioxide OBrO (g) 165.6 156.0 ± 2.1 kJ/mol 111.9028 ± 0.0012 21255-83-4*0 Cyclopropylium [CH(CH2CH2)]+ (g, TS) 1101.58 1088.77 ± 0.73 kJ/mol 41.0713 ± 0.0024 1724-43-2*200 Nitrosyl nitrate ON(O2)NO (g, perp) 70.6 62.3 ± 1.8 kJ/mol 92.0111 ± 0.0012 *15969-55-8*0 Propyne cation [CH3CCH]+ (g) 1192.68 1186.96 ± 0.38 kJ/mol 40.0633 ± 0.0024 34526-53-9*0 Acetylene anion [HCCH]- (g, trans ?) 356.9 356.7 ± 1.9 kJ/mol 26.0378 ± 0.0016 50443-89-5*1 Nitrosyl fluoride FNO (g) -85.48 -87.85 ± 0.76 kJ/mol 49.00454 ± 0.00031 7789-25-5*0 Cyclopropylidene C(CH2CH2) (g, triplet) 544.8 536.0 ± 1.5 kJ/mol 40.0639 ± 0.0024 2143-70-6*2 Dihydrooxooxygen cation [(H2O)O]+ (g) 994.9 988.2 ± 1.6 kJ/mol 34.01413 ± 0.00062 177329-59-8*0 Propynylidene cation [HCCCH]+ (g) 1409.62 1412.18 ± 0.83 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 Deuterium atom cation D+ (g) 1532.210 1534.123 ± 0.000 kJ/mol 2.01355319809 ± 0.00000000040 14464-47-2*0 Dihydrogen fluoride anion [(HF)(H)]- (g, singlet) -61.9 -60.5 ± 3.2 kJ/mol 21.01483 ± 0.00014 117339-92-1*2 Perchloryloxy OCl(O)(O)O (g) 248.4 240.8 ± 1.8 kJ/mol 99.4503 ± 0.0015 12133-63-0*0 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) -178.18 ± 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 Fluorosyl fluoride anion [FFO]- (g, doublet) -147.1 -146.8 ± 3.0 kJ/mol 53.99675 ± 0.00030 *86825-57-2*2 Cyclopentane CH2(CH2CH2CH2CH2) (l) -104.68 ± 0.38 kJ/mol 70.1329 ± 0.0041 287-92-3*590 2-Methylpentane CH3CH2CH2CH(CH3)2 (g) -134.46 -173.72 ± 0.73 kJ/mol 86.1754 ± 0.0049 107-83-5*0 3-Methylpentane CH3CH2CH(CH3)CH2CH3 (g) -131.91 -171.41 ± 0.76 kJ/mol 86.1754 ± 0.0049 96-14-0*0 2,3-Dimethylbutane CH3CH(CH3)CH(CH3)CH3 (g) -136.49 -177.59 ± 0.81 kJ/mol 86.1754 ± 0.0049 79-29-8*0 Cyclohexane CH2(CH2CH2CH2CH2CH2) (l) -131.79 -155.92 ± 0.28 kJ/mol 84.1595 ± 0.0049 110-82-7*500 1,5-Hexadiene CH2CHCH2CH2CHCH2 (g) 108.51 83.92 ± 0.39 kJ/mol 82.1436 ± 0.0049 592-42-7*0 1-Hydroxyethyl CH3CHOH (g) -42.71 -56.14 ± 0.46 kJ/mol 45.0605 ± 0.0017 2348-46-1*0 2-Hydroxyethyl CH2CH2OH (g, staggered-anti) -5.8 -18.2 ± 1.5 kJ/mol 45.0605 ± 0.0017 4422-54-2*3 Chlorite [OClO]- (g) -105.51 -107.69 ± 0.37 kJ/mol 67.4520 ± 0.0011 14998-27-7*0 1-Hydroxyethenyl anion [CH2COH]- (g, syn) 15.1 7.8 ± 2.1 kJ/mol 43.0452 ± 0.0016 112539-13-6*22 (E)-Diazene anion [HNNH]- (g, trans) 265.6 258.7 ± 2.0 kJ/mol 30.02991 ± 0.00020 *59952-06-6*0 Dicarbon monoxide cation [CCO]+ (g) 1433.9 1439.0 ± 2.1 kJ/mol 40.0203 ± 0.0016 12287-08-0*0 (Z)-Diazene cation [HNNH]+ (g, cis) 1157.0 1150.2 ± 1.3 kJ/mol 30.02881 ± 0.00020 86631-37-0*0 C=O-C cation [COC]+ (g, quartet) 1816.9 1820.9 ± 2.0 kJ/mol 40.0203 ± 0.0016 83483-98-1*2 Trioxidanyl HOOO (g, cis) 26.35 23.08 ± 0.19 kJ/mol 49.00614 ± 0.00090 12500-78-6*2 Oxirene anion [O(CHCH)]- (g) 288.2 285.2 ± 2.2 kJ/mol 42.0372 ± 0.0016 *157-18-6*0 Iminomethide [HCNH]- (g, cis) 252.7 248.9 ± 1.8 kJ/mol 28.03387 ± 0.00082 90623-30-6*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) -378.47 -391.56 ± 0.62 kJ/mol 48.0413 ± 0.0010 463-57-0*0 1-Hydrazinylium-1-yl [NNH2]+ (g) 1143.4 1136.4 ± 1.4 kJ/mol 30.02881 ± 0.00020 63986-30-1*0 Ethoxyoxoniumylidene [CH3CH2OO]+ (g, cis singlet) 962.4 945.9 ± 1.7 kJ/mol 61.0594 ± 0.0017 268728-77-4*22 2-Hydroperoxyethylium [CH2CH2OOH]+ (g, triplet) 999.8 988.9 ± 1.7 kJ/mol 61.0594 ± 0.0017 *84824-62-4*1 Hydrogen cyanide cation [HCN]+ (g) 1442.54 1442.07 ± 0.20 kJ/mol 27.02483 ± 0.00081 12601-62-6*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 Iodine I (g, 2P1/2) 198.109 197.709 ± 0.0021 kJ/mol 126.904470 ± 0.000030 14362-44-8*2 Dioxirane cation [CH2(OO)]+ (g) 1050.8 1043.1 ± 2.0 kJ/mol 46.0248 ± 0.0010 232262-10-1*0 Dioxymethyl cation [CH2OO]+ (g) 1074.8 1068.4 ± 1.7 kJ/mol 46.0248 ± 0.0010 232262-11-2*0 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 -76.78 ± 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 Dihydrogen fluoride (H)(HF) (g) -55.9 -54.9 ± 1.6 kJ/mol 21.01428 ± 0.00014 12592-22-2*1 Bifluoride [FHF]- (g) -705.22 -709.07 ± 0.35 kJ/mol 39.005295 ± 0.000070 18130-74-0*0 Cyanato cation [NCO]+ (g) 1261.52 1262.03 ± 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 Aminyliumyl [NH]+ (g) 1659.04 1659.97 ± 0.23 kJ/mol 15.014131 ± 0.000099 19067-62-0*0 Nitrilomethylium [CN]+ (g) 1783.14 1786.62 ± 0.48 kJ/mol 26.01689 ± 0.00080 12539-57-0*0 Fluorodioxidenium [FOO]+ (g) 1221.9 1219.5 ± 2.0 kJ/mol 50.99665 ± 0.00060 139584-95-5*0 Diazenide [NNH]- (g, triplet) 347.5 344.6 ± 1.6 kJ/mol 29.02197 ± 0.00016 71004-29-0*1 Glyoxal OCHCHO (g, cis) -189.37 -194.81 ± 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 Dimethylaminylium [(CH3)2N]+ (g) 1040.9 1025.5 ± 1.8 kJ/mol 44.0752 ± 0.0017 49784-85-2*0 Trichlorine cation [Cl3]+ (g, singlet) 1056.6 1055.5 ± 1.4 kJ/mol 106.3576 ± 0.0027 33088-85-6*2 Fluorodioxidanide [FOO]- (g) -256.8 -256.1 ± 1.9 kJ/mol 50.99775 ± 0.00060 23553-17-5*0 Hydroxylamine NH2OH (g, cis) -15.3 -25.9 ± 1.4 kJ/mol 33.02996 ± 0.00037 7803-49-8*2 Hydroxylamine cation [NH2OH]+ (g) 857.7 847.9 ± 1.6 kJ/mol 33.02941 ± 0.00037 62675-55-2*0 Ethylimidogen CH3CH2N (g) 306.1 291.5 ± 2.0 kJ/mol 43.0678 ± 0.0016 27770-44-1*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 Dioxofluorine OFO (g) 523.9 523.2 ± 1.0 kJ/mol 50.99720 ± 0.00060 175861-93-5*0 Diazirenide [HC(NN)]- (g) 454.9 452.2 ± 1.5 kJ/mol 41.03267 ± 0.00082 130614-84-5*0 Trioxidaniumyl [HOOOH]+ (g, c, t) 935.2 926.1 ± 1.5 kJ/mol 50.01353 ± 0.00091 161321-37-5*3 Cyanamide cation [NH2CN]+ (g) 1158.8 1152.4 ± 1.5 kJ/mol 42.03951 ± 0.00082 148556-23-4*0 Nitrogen hydride oxide NH3O (g) 72.2 61.0 ± 1.3 kJ/mol 33.02996 ± 0.00037 38544-48-8*0 3-Diaziridinylidene C(NHNH) (g, anti) 521.8 515.0 ± 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 Dichloromethylene CCl2 (g, triplet) 313.98 315.18 ± 0.90 kJ/mol 82.9161 ± 0.0020 1605-72-7*1 Trioxidanylium [HOOO]+ (g, cis) 1085.5 1079.2 ± 1.4 kJ/mol 49.00559 ± 0.00090 74241-49-9*2 Chlorine difluoride anion [FClF]- (g) -504.9 -505.8 ± 1.9 kJ/mol 73.45005 ± 0.00090 16892-05-0*0 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 Trichloride [Cl3]- (g) -328.5 -327.6 ± 1.3 kJ/mol 106.3586 ± 0.0027 18434-33-8*0 Aminooxy cation [NH2O]+ (g) 945.97 938.84 ± 0.76 kJ/mol 32.02147 ± 0.00034 *51375-41-8*0 1,1,1,2-Tetrachloroethane CH2ClCCl3 (cr,l) -193.5 ± 1.1 kJ/mol 167.8481 ± 0.0039 630-20-6*500 Hexachloroethane CCl3CCl3 (cr,l) -214.2 ± 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) 5.63 0.21 ± 0.55 kJ/mol 96.9427 ± 0.0024 156-60-5*0 Ethynylene cation [C2]+ (g) 1964.97 1971.55 ± 0.40 kJ/mol 24.0209 ± 0.0016 12595-79-8*0 Trifluoride ion [F3]- (g) -348.6 -349.4 ± 2.5 kJ/mol 56.9957582 ± 0.0000015 25730-99-8*0 Chlorine difluoride ClFF (g) 22.5 23.9 ± 1.9 kJ/mol 73.44951 ± 0.00090 91483-78-2*0 Fluorochlorobromomethane CHFClBr (g) -218.2 -230.9 ± 4.9 kJ/mol 147.3737 ± 0.0016 593-98-6*0 Fluorine atom cation F+ (g) 1758.301 1760.600 ± 0.017 kJ/mol 18.99785462 ± 0.00000050 14701-13-4*0 Fluoromethyliumyl [CHF]+ (g) 1116.6 1116.9 ± 1.7 kJ/mol 32.01649 ± 0.00080 89877-52-1*0 Fluoromethylene anion [CHF]- (g) 95.96 96.49 ± 0.61 kJ/mol 32.01759 ± 0.00080 71267-42-0*0 Polytetrafluoroethylene CF2CF2 (s) -829.92 ± 0.54 kJ/mol 100.0150 ± 0.0016 9002-84-0*591 Azidonitrene NNNN (g, C2h) 660.8 657.7 ± 1.6 kJ/mol 56.02696 ± 0.00028 147363-92-6*1 Hydroxyaminylium [HNOH]+ (g, cis) 1048.5 1041.3 ± 2.6 kJ/mol 32.02147 ± 0.00034 66097-71-0*2 trans-1,2-Difluoroethene CHFCHF (g, trans) -299.75 -306.19 ± 0.84 kJ/mol 64.0341 ± 0.0016 1630-78-0*0 Ammonium hydroxide NH4OH (cr,l) -360.45 -361.53 ± 0.57 kJ/mol 35.04584 ± 0.00047 1336-21-6*500 Hydroxyamidogen anion [HNOH]- (g) 90.7 84.8 ± 2.8 kJ/mol 32.02257 ± 0.00034 *66097-71-0*0 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 Fluoroisoformyl cation [COF]+ (g) 1347.4 1349.5 ± 1.9 kJ/mol 47.00795 ± 0.00085 *1871-25-6*0 o-Benzyne cation [C6H4]+ (g) 1392.2 1384.2 ± 1.6 kJ/mol 76.0954 ± 0.0048 70220-84-7*0 Ammonium hydroxide NH4OH (aq) -362.833 ± 0.061 kJ/mol 35.04584 ± 0.00047 1336-21-6*800 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) 603.6 594.3 ± 1.2 kJ/mol 76.0960 ± 0.0048 3355-34-8*1 1,3-Cycloheptadiene CH2(CHCHCHCHCH2CH2) (g, c-c) 123.64 94.53 ± 0.78 kJ/mol 94.1543 ± 0.0056 4054-38-0*1 Tropylium [CH(CHCHCHCHCHCH)]+ (g) 899.0 879.3 ± 1.1 kJ/mol 91.1299 ± 0.0056 26811-28-9*0 Hydrogen fluoride HF (aq, 22 H2O) -321.85 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*902 1-Chloro ozone anion [ClOOO]- (g, perp) -109.0 -111.5 ± 2.2 kJ/mol 83.4514 ± 0.0013 224299-15-4*3 Hexafluorobenzene C6F6 (cr,l) -997.14 -983.36 ± 0.87 kJ/mol 186.0546 ± 0.0048 392-56-3*500 Methyleneoxonium cation [CH2OH2]+ (g) 827.8 818.3 ± 1.7 kJ/mol 32.04131 ± 0.00090 *177788-17-9*0 cis-1,2-Dibromoethene CHBrCHBr (g, cis) 121.3 100.8 ± 2.0 kJ/mol 185.8453 ± 0.0026 590-11-4*0 1,1-Dibromoethane CH3CHBr2 (g) -4.8 -31.8 ± 1.8 kJ/mol 187.8612 ± 0.0026 557-91-5*0 Dioxaziridinyl cation [N(OO)]+ (g) 1365.9 1363.3 ± 1.7 kJ/mol 46.00499 ± 0.00060 *66252-29-7*0 Nitrous acid HONO (g) -72.985 -78.642 ± 0.078 kJ/mol 47.01348 ± 0.00061 7782-77-6*0 Carbamoyl HNCOH (g, trans-trans) 74.1 67.7 ± 2.7 kJ/mol 44.03272 ± 0.00087 *2858-51-7*1 Formaldiminoxy CH2NO (g) 160.9 154.0 ± 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 Dioxaziridinyl anion [N(OO)]- (g) 295.9 293.4 ± 1.7 kJ/mol 46.00609 ± 0.00060 66252-31-1*0 Peroxyimidogen cation [NOO]+ (g) 1409.7 1406.8 ± 1.9 kJ/mol 46.00499 ± 0.00060 *60488-32-6*0 Chlorine oxide peroxide OClOO (g, vdW) 226.5 227.4 ± 2.5 kJ/mol 83.4509 ± 0.0013 141801-67-4*100 2-Methylene-2H-azirine (CHN)CCH2 (g) 404.4 397.0 ± 1.7 kJ/mol 53.0627 ± 0.0024 110027-86-6*0 Hydroxymethylene cation [HCOH]+ (g, cis) 986.4 982.8 ± 1.6 kJ/mol 30.02543 ± 0.00087 135395-06-1*2 Peroxyimidogen anion [NOO]- (g) 165.0 162.7 ± 1.7 kJ/mol 46.00609 ± 0.00060 60488-31-5*0 Hydroxymethylene cation [HCOH]+ (g, gauche quartet) 1482.1 1479.4 ± 1.9 kJ/mol 30.02543 ± 0.00087 135395-06-1*3 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 Hydroxymethylene anion [HCOH]- (g, cis) 160.2 157.5 ± 1.7 kJ/mol 30.02653 ± 0.00087 207914-87-2*2 2-Isocyanovinyl CHCHNC (g, syn) 544.7 542.7 ± 1.7 kJ/mol 52.0547 ± 0.0024 225798-14-1*2 Cyanomethylene HCCN (g, singlet) 529.4 530.5 ± 1.3 kJ/mol 39.0361 ± 0.0016 2612-62-6*2 Isocyanomethylene HCNC (g, triplet) 585.3 586.3 ± 1.6 kJ/mol 39.0361 ± 0.0016 78694-65-2*2 Hydroxymethylene anion [HCOH]- (g, gauche quartet) 334.0 334.8 ± 2.1 kJ/mol 30.02653 ± 0.00087 207914-87-2*3 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 Tetraoxidanyl (HOO)(O2) (g, vdW) 2.1 0.4 ± 2.9 kJ/mol 65.0055 ± 0.0012 69696-93-1*100 Vinylvinylidene cation [CH2CHCHC]+ (g, trans) 1429.9 1424.3 ± 2.0 kJ/mol 52.0740 ± 0.0032 161054-20-2*1 1,2-Butadien-1-ylidene CH3CHCC (g, singlet) 511.9 506.3 ± 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 Aquacarbon H2OC (g, singlet vdW) 467.6 465.5 ± 1.9 kJ/mol 30.02598 ± 0.00087 81434-73-3*102 Butyraldehyde CH3CH2CH2CHO (g) -185.27 -205.64 ± 0.85 kJ/mol 72.1057 ± 0.0033 123-72-8*0 Aquacarbon cation [H2OC]+ (g) 1196.1 1193.0 ± 1.7 kJ/mol 30.02543 ± 0.00087 *81434-73-3*0 Chloroallene CH2CCHCl (g) 181.9 175.2 ± 1.6 kJ/mol 74.5086 ± 0.0026 3223-70-9*0 1-Chloropropyne CH3CCCl (g) 192.0 187.9 ± 1.6 kJ/mol 74.5086 ± 0.0026 7747-84-4*0 Nirous oxide cation [NNO]+ (g) 1329.70 1326.80 ± 0.12 kJ/mol 44.01233 ± 0.00033 12269-46-4*0 Methylcyclopentane CH3CH(CH2CH2CH2CH2) (g) -68.59 -106.12 ± 0.36 kJ/mol 84.1595 ± 0.0049 96-37-7*0 Dioxosilane SiO2 (cr,l) -906.76 -911.74 ± 0.63 kJ/mol 60.08430 ± 0.00067 7631-86-9*500 Dioxosilane SiO2 (vitr) -826.31 -902.24 ± 0.65 kJ/mol 60.08430 ± 0.00067 7631-86-9*520 Ethane cation [CH3CH3]+ (g) 1043.15 1029.14 ± 0.59 kJ/mol 30.0685 ± 0.0017 34488-65-8*0 Silicon carbide cation [SiC]+ (g) 1602.0 1606.6 ± 2.6 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 Difluorosilyliumyl [SiF2]+ (g) 415.0 414.2 ± 2.0 kJ/mol 66.08176 ± 0.00030 37300-76-8*0 Fluoroniumyl ion [HF]+ (g) 1275.556 1275.788 ± 0.022 kJ/mol 20.005795 ± 0.000070 12381-92-9*0 Silyliumyl [SiH2]+ (g) 1155.45 1153.83 ± 0.93 kJ/mol 30.10083 ± 0.00033 28149-31-7*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) 393.3 384.8 ± 2.2 kJ/mol 60.20276 ± 0.00066 15435-77-5*1 Di-mu-hydrodihydrodisilicon HSi(HSiHH) (g, cis-singlet) 385.6 375.2 ± 2.6 kJ/mol 60.20276 ± 0.00066 129970-82-7*22 Iodosilane SiH3I (g) 6.9 -2.8 ± 2.6 kJ/mol 158.01379 ± 0.00037 13598-42-0*0 Nitric acid HON(O)O (cr,l) -178.98 -173.26 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*500 Trimethylsilanide [Si(CH3)3]- (g) -42.0 -65.5 ± 2.2 kJ/mol 73.1896 ± 0.0025 54711-92-1*0 Oxadiazirine anion [O(NN)]- (g) 95.1 95.5 ± 2.9 kJ/mol 44.01343 ± 0.00033 350586-31-1*0 1-Chloro ozone anion [ClOOO]- (g, cis) -66.9 -68.8 ± 2.1 kJ/mol 83.4514 ± 0.0013 224299-15-4*1 (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) 419.5 403.6 ± 2.0 kJ/mol 78.1118 ± 0.0048 124869-33-6*0 Pentatetraene CH2CCCCH2 (g) 452.7 448.7 ± 1.2 kJ/mol 64.0853 ± 0.0040 21986-03-8*0 Ethylammoniumyl [CH3CH2NH2]+ (g) 827.6 807.6 ± 1.6 kJ/mol 45.0832 ± 0.0017 41857-50-5*0 Trioxodinitrate anion [ONN(O)O]- (g, vdW) -104.2 -107.5 ± 1.9 kJ/mol 76.01223 ± 0.00091 194856-62-7*100 2-Methyl-2-propanamine (CH3)3CNH2 (g) -87.01 -120.66 ± 0.55 kJ/mol 73.1369 ± 0.0033 75-64-9*0 Ethylene anion [CH2CH2]- (g, anti ?) 232.1 224.5 ± 2.0 kJ/mol 28.0537 ± 0.0016 34527-91-8*1 Benzophenone C6H5C(O)C6H5 (g) 80.7 51.5 ± 1.5 kJ/mol 182.2179 ± 0.0104 119-61-9*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 Peroxyformic acid HC(O)OOH (g, gauche) -265.2 -273.1 ± 1.4 kJ/mol 62.0248 ± 0.0012 107-32-4*3 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 Oxosulfur [SO]+ (g) 999.26 999.87 ± 0.13 kJ/mol 48.0649 ± 0.0060 767269-11-4*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 Hydrofluorate ion [HF]- (g) -75.6 -75.1 ± 1.8 kJ/mol 20.006892 ± 0.000070 37249-79-9*0 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 -73.09 ± 0.37 kJ/mol 62.1350 ± 0.0062 75-08-1*500 Dimethylsulfoxide CH3S(O)CH3 (cr,l) -201.93 -203.58 ± 0.49 kJ/mol 78.1344 ± 0.0062 67-68-5*500 Carbon monosulfide CS (g) 278.92 282.16 ± 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 Hydrogen fluoride HF (aq, 60 H2O) -321.97 ± 0.10 kJ/mol 20.006343 ± 0.000070 7664-39-3*823 Fluoroaminyliumyl [NF]+ (g) 1415.09 1415.63 ± 0.85 kJ/mol 33.004595 ± 0.000070 33146-36-0*0 Cyclohexene CH2(CHCHCH2CH2CH2) (g) 27.18 -4.28 ± 0.32 kJ/mol 82.1436 ± 0.0049 110-83-8*0 Cyclohexene CH2(CHCHCH2CH2CH2) (cr,l) -21.97 -37.84 ± 0.30 kJ/mol 82.1436 ± 0.0049 110-83-8*500 Aminomethyl anion [CH2NH2]- (g) 209.5 199.3 ± 2.1 kJ/mol 30.04975 ± 0.00085 74215-21-7*0 1-Hydroxyethanide [CH3CHOH]- (g) -20.3 -33.7 ± 2.2 kJ/mol 45.0610 ± 0.0017 88032-18-2*0 Diazenium [NH2NH]+ (g) 968.67 957.41 ± 0.73 kJ/mol 31.03675 ± 0.00025 37369-93-0*0 Methylaminilium [CH3NH]+ (g) 1135.2 1125.4 ± 2.1 kJ/mol 30.04865 ± 0.00085 49784-84-1*0 Dibromine Br2 (aq) -2.25 ± 0.18 kJ/mol 159.8080 ± 0.0020 7726-95-6*800 Hydrogen fluoride HF (aq, 5 H2O) -321.317 ± 0.099 kJ/mol 20.006343 ± 0.000070 7664-39-3*809 (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 Methyliumylamino [CH2NH]+ (g) 1056.1 1049.2 ± 1.7 kJ/mol 29.04071 ± 0.00083 65130-65-6*0 Azanidylmethyl [CH2NH]- (g) 224.4 217.1 ± 2.2 kJ/mol 29.04181 ± 0.00083 127593-73-1*0 Acetaldehyde anion [CH3CHO]- (g) -62.1 -72.4 ± 2.2 kJ/mol 44.0531 ± 0.0017 60427-04-5*0 Aminomethyliumyl [CHNH2]+ (g) 1039.5 1031.8 ± 2.3 kJ/mol 29.04071 ± 0.00083 89302-94-3*0 Fluorosyl fluoride anion [FFO]- (g, quartet) -56.6 -55.7 ± 2.4 kJ/mol 53.99675 ± 0.00030 *86825-57-2*1 Aminomethylene anion [CHNH2]- (g) 353.0 346.1 ± 2.3 kJ/mol 29.04181 ± 0.00083 207914-86-1*0 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 Methylimidogen anion [CH3N]- (g) 321.1 313.4 ± 1.3 kJ/mol 29.04181 ± 0.00083 82539-34-2*0 Oxoethenylium [HCCO]+ (g) 1139.7 1142.5 ± 2.1 kJ/mol 41.0282 ± 0.0016 92056-63-8*0 Methyleneaminylium [CH2N]+ (g, triplet) 1456.7 1453.1 ± 2.1 kJ/mol 28.03277 ± 0.00082 53518-13-1*1 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 Oxiranylidene CH2(CO) (g, triplet) 456.2 452.1 ± 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) 833.7 819.7 ± 2.0 kJ/mol 48.0407 ± 0.0010 112465-88-0*0 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 Oxybismethanol HOCH2OCH2OH (g, C1 I) -534.1 -557.2 ± 1.9 kJ/mol 78.0672 ± 0.0019 4407-89-0*11 Methoxyoxoniumylidene [CH3OO]+ (g) 1012.32 1003.49 ± 0.67 kJ/mol 47.0328 ± 0.0010 86475-50-5*0 Ethylperoxy CH3CH2OO (g, trans) -5.43 -21.54 ± 0.88 kJ/mol 61.0599 ± 0.0017 3170-61-4*1 Ammonium radical NH4 (g) 190.01 179.43 ± 0.43 kJ/mol 18.03850 ± 0.00029 92075-50-8*0 Aminomethyliumylidene [CNH2]+ (g) 1168.3 1165.1 ± 2.2 kJ/mol 28.03277 ± 0.00082 86784-42-1*0 2-Chloro ozone anion [ClO(O)O]- (g) -103.6 -105.9 ± 3.2 kJ/mol 83.4514 ± 0.0013 *141801-67-4*0 Formic acid HC(O)OH (cr,l) -431.49 -424.66 ± 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 Nitrosyl nitrate ONONO2 (g, trans) 48.3 40.3 ± 1.8 kJ/mol 92.0111 ± 0.0012 15969-55-8*1 Dioxymethyl anion [CH2OO]- (g) 54.8 49.7 ± 1.4 kJ/mol 46.0259 ± 0.0010 93207-29-5*0 Chlorosyl chloride cation [ClClO]+ (g) 1132.6 1130.8 ± 2.0 kJ/mol 86.9043 ± 0.0018 *86825-56-1*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 Chlorosyl chloride anion [ClClO]- (g) -185.4 -184.7 ± 2.3 kJ/mol 86.9053 ± 0.0018 *86825-55-0*0 2-Propanol CH3CH(OH)CH3 (cr,l) -305.35 -318.15 ± 0.27 kJ/mol 60.0950 ± 0.0025 67-63-0*500 1-Propanol CH3CH2CH2OH (cr,l) -290.27 -302.45 ± 0.19 kJ/mol 60.0950 ± 0.0025 71-23-8*500 Carbon tetracation [C]+4 (g) 14993.616 14998.762 ± 0.050 kJ/mol 12.00851 ± 0.00080 16092-62-9*0 Hypofluorous acid cation [HOF]+ (g) 1142.01 1139.00 ± 0.87 kJ/mol 36.00519 ± 0.00031 90243-22-4*0 Oxazirinyl cation [C(NO)]+ (g) 1565.5 1566.3 ± 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) -484.03 -483.60 ± 0.18 kJ/mol 60.0520 ± 0.0017 64-19-7*500 Acetic acid CH3C(O)OH (aq, 75 H2O) -484.61 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*825 Acetic acid CH3C(O)OH (aq, 1500 H2O) -484.81 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*840 Ethyl formate HC(O)OCH2CH3 (cr,l) -425.9 ± 1.1 kJ/mol 74.0785 ± 0.0025 109-94-4*500 Chloryl chloride ClCl(O)O (g) 126.1 122.1 ± 1.7 kJ/mol 102.9042 ± 0.0019 117489-73-3*0 Imidogen anion [NH]- (g) 322.63 322.68 ± 0.16 kJ/mol 15.015229 ± 0.000099 23841-33-0*0 Water H2O (l, eq.press.) -285.804 ± 0.022 kJ/mol 18.01528 ± 0.00033 7732-18-5*589 Propionic acid CH3CH2C(O)OH (g, anti) -415.5 -433.1 ± 1.3 kJ/mol 74.0785 ± 0.0025 79-09-4*2 Imidogen NH (g, triplet) 358.75 358.80 ± 0.16 kJ/mol 15.014680 ± 0.000099 13774-92-0*1 Chloroniumyl ion [HCl]+ (g) 1137.798 1137.732 ± 0.0051 kJ/mol 36.46009 ± 0.00090 12258-94-5*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) 1108.3 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 Carbon C (g, triplet) 711.400 716.885 ± 0.040 kJ/mol 12.01070 ± 0.00080 7440-44-0*1 Dioxodiazoxane ONONO (g, t, c) 109.3 105.3 ± 1.8 kJ/mol 76.01168 ± 0.00091 122413-35-8*2 Bromine atom Br (g, 2P3/2) 117.925 111.863 ± 0.055 kJ/mol 79.90400 ± 0.00100 10097-32-2*1 Carbon C (g, singlet) 833.331 838.477 ± 0.040 kJ/mol 12.01070 ± 0.00080 7440-44-0*2 Cyanogen cation [NCCN]+ (g) 1598.26 1600.48 ± 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 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) 410.1 413.7 ± 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 Hydrogen fluoride HF (aq, 18 H2O) -321.81 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*901 Isocyanomethylium [CH2NC]+ (g) 1272.6 1270.5 ± 2.2 kJ/mol 40.0435 ± 0.0016 78269-43-9*0 Diazirinyl HC(NN) (g, 2A') 557.1 553.9 ± 2.0 kJ/mol 41.03212 ± 0.00082 69967-71-1*2 1-Propenylidene CH3CHC (g, triplet) 630.5 623.0 ± 1.7 kJ/mol 40.0639 ± 0.0024 70277-78-0*2 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 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 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 Acetylene anion [HCCH]- (g, cis ?) 380.1 380.4 ± 1.9 kJ/mol 26.0378 ± 0.0016 50443-89-5*2 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, 74 H2O) -165.544 ± 0.024 kJ/mol 36.46064 ± 0.00090 7647-01-0*953 Trichloromethylium [CCl3]+ (g) 856.07 854.55 ± 0.93 kJ/mol 118.3683 ± 0.0028 27130-34-3*0 Dichloromethyliumyl [CCl2]+ (g) 1121.9 1122.9 ± 1.8 kJ/mol 82.9156 ± 0.0020 55945-51-2*0 Ammonium chloride (NH4)Cl (cr) -311.553 -314.715 ± 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 Tribromine Br3 (g) 156.0 134.3 ± 3.2 kJ/mol 239.7120 ± 0.0030 11094-39-6*0 Fluorosyl fluoride cation [FFO]+ (g, quartet) 1413.1 1413.4 ± 3.5 kJ/mol 53.99566 ± 0.00030 *86825-50-5*1 Hydrogen difluoride cation [FFH]+ (g, singlet) 1174.3 1171.3 ± 1.5 kJ/mol 39.004198 ± 0.000070 *126950-54-7*2 Hydrogen chloride HCl (aq, 75 H2O) -165.554 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*825 1,1,1-Trichloroethane CH3CCl3 (l) -183.85 -177.21 ± 0.52 kJ/mol 133.4033 ± 0.0031 71-55-6*500 Aminooxy anion [NH2O]- (g) 47.3 40.4 ± 1.7 kJ/mol 32.02257 ± 0.00034 51375-41-8*0 Vinyl chloride CH2CHCl (cr,l) -3.60 0.96 ± 0.91 kJ/mol 62.4979 ± 0.0018 75-01-4*500 Triazirinylium ion [N(NN)]+ (g) 1609.0 1606.1 ± 1.6 kJ/mol 42.01967 ± 0.00021 92220-05-8*0 Triazirine HN(NN) (g) 464.2 457.7 ± 2.6 kJ/mol 43.02816 ± 0.00022 157-29-9*0 Chloromethane cation [CH3Cl]+ (g) 1014.56 1007.79 ± 0.18 kJ/mol 50.4867 ± 0.0012 12538-71-5*0 Bromofluoromethane CH2FBr (g) -197.4 -211.9 ± 4.9 kJ/mol 112.9290 ± 0.0013 373-52-4*0 Hydrogen fluoride HF (aq, 40 H2O) -321.92 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*821 Fluorodibromomethane CHFBr2 (g) -159.7 -179.2 ± 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 2-Propenylidyne anion [CH2CHC]- (g) 464.6 460.9 ± 1.7 kJ/mol 39.0565 ± 0.0024 120126-89-8*0 Nitrate [ON(O)O]- (aq) -206.55 ± 0.18 kJ/mol 62.00549 ± 0.00090 14797-55-8*800 Hypochlorous acid cation [HOCl]+ (g) 998.94 995.89 ± 0.90 kJ/mol 52.45949 ± 0.00095 71606-47-8*0 2-Propen-3-yliumylidene [CHCHCH]+ (g) 1494.5 1491.5 ± 1.7 kJ/mol 39.0554 ± 0.0024 84654-86-4*0 Cyanogen bromide anion [BrCN]- (g) 57.9 54.3 ± 3.8 kJ/mol 105.9220 ± 0.0013 54092-05-6*0 Hypofluorous acid anion [HOF]- (g, quartet) 155.3 154.7 ± 2.6 kJ/mol 36.00629 ± 0.00031 36505-07-4*2 2-Propenylidene anion [CHCHCH]- (g) 536.0 532.6 ± 1.7 kJ/mol 39.0565 ± 0.0024 98705-30-7*0 Chlorine difluoride cation [ClFF]+ (g) 1346.3 1344.9 ± 2.1 kJ/mol 73.44896 ± 0.00090 86825-59-4*0 1,2-Difluoroacetylene cation [FCCF]+ (g) 1081.7 1084.5 ± 1.3 kJ/mol 62.0177 ± 0.0016 268566-70-7*0 Difluorophosgene cation [CF2O]+ (g) 653.44 650.68 ± 0.51 kJ/mol 66.00636 ± 0.00085 73256-56-1*0 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 Hypochlorous acid anion [HOCl]- (g) 198.7 198.4 ± 2.5 kJ/mol 52.46059 ± 0.00095 34524-94-2*0 Trifluorine cation [F3]+ (g) 1530.0 1527.9 ± 2.2 kJ/mol 56.9946610 ± 0.0000015 64710-22-1*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) 119.2 117.9 ± 2.7 kJ/mol 64.4707 ± 0.0012 331419-80-8*2 Tribromide [Br3]- (g) -287.4 -308.5 ± 1.9 kJ/mol 239.7125 ± 0.0030 14522-80-6*0 Dibromophosgene CBr2O (l) -143.98 ± 0.95 kJ/mol 187.8181 ± 0.0022 593-95-3*590 2-Chloroethanol ClCH2CH2OH (l) -314.90 ± 0.53 kJ/mol 80.5132 ± 0.0019 107-07-3*590 2-Bromoethanol BrCH2CH2OH (l) -274.37 ± 0.46 kJ/mol 124.9645 ± 0.0019 540-51-2*590 Hydrooxonitrate [HNO]- (g) 78.60 75.68 ± 0.99 kJ/mol 31.01463 ± 0.00032 66057-02-1*0 Ozone cation [OOO]+ (g) 1352.880 1350.541 ± 0.041 kJ/mol 47.99765 ± 0.00090 12596-82-6*0 Phenylium [C6H5]+ (g, singlet) 1149.27 1136.49 ± 0.85 kJ/mol 77.1034 ± 0.0048 17333-73-2*2 2-Cyclopropyn-1-ylidene C(CC) (g, singlet) 993.2 1000.0 ± 2.6 kJ/mol 36.0321 ± 0.0024 102508-15-6*2 Hydrogen carbonate [HOC(O)O]- (aq) -689.865 ± 0.039 kJ/mol 61.0174 ± 0.0012 71-52-3*800 Hydroxyimidogen anion [NOH]- (g) 229.8 227.4 ± 2.2 kJ/mol 31.01463 ± 0.00032 *35337-59-8*0 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 Methanol anion [CH3OH]- (g) -89.0 -99.7 ± 2.8 kJ/mol 32.04241 ± 0.00090 68474-04-4*0 2-Cyclopropyn-1-yl anion [C(CC)]- (g) 664.6 671.9 ± 1.6 kJ/mol 36.0326 ± 0.0024 500574-36-7*0 Tetranitrogen cation [NNNN]+ (g) 1392.8 1392.5 ± 1.5 kJ/mol 56.02641 ± 0.00028 12185-04-5*0 Cycloheptane CH2(CH2CH2CH2CH2CH2CH2) (cr,l) -126.58 -156.47 ± 0.50 kJ/mol 98.1861 ± 0.0057 291-64-5*500 Propynylidene HCCCH (g) 543.73 546.73 ± 0.58 kJ/mol 38.0480 ± 0.0024 67152-18-5*0 Ethylbenzene C6H5CH2CH3 (cr,l) -12.30 ± 0.52 kJ/mol 106.1650 ± 0.0064 100-41-4*500 Hydrogen chloride HCl (aq, 140 H2O) -165.944 ± 0.024 kJ/mol 36.46064 ± 0.00090 7647-01-0*907 Phenylacetylene C6H5CCH (cr,l) 273.85 ± 0.70 kJ/mol 102.1332 ± 0.0064 536-74-3*500 Chlorine difluoride anion [ClFF]- (g) -319.0 -319.0 ± 2.2 kJ/mol 73.45005 ± 0.00090 91419-41-9*0 Indane C6H4(CH2CH2CH2) (cr,l) 25.44 10.96 ± 0.76 kJ/mol 118.1757 ± 0.0072 496-11-7*500 Indene C6H4(CHCHCH2) (cr,l) 117.27 109.98 ± 0.85 kJ/mol 116.1598 ± 0.0072 95-13-6*500 Phenyloxoniumylidene [C6H5O]+ (g) 898.6 884.2 ± 1.4 kJ/mol 93.1028 ± 0.0048 41071-17-4*0 Fluorobenzene C6H5F (cr,l) -148.74 -146.32 ± 0.39 kJ/mol 96.1023 ± 0.0048 462-06-6*500 Bromobenzene C6H5Br (cr,l) 60.3 ± 1.3 kJ/mol 157.0079 ± 0.0049 108-86-1*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 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) -244.55 -247.67 ± 0.26 kJ/mol 58.0791 ± 0.0025 67-64-1*500 Peroxychloric acid HOOCl(O)O (g) 76.6 68.4 ± 2.5 kJ/mol 100.4582 ± 0.0015 177778-91-5*0 Formaldehyde anion [CH2O]- (g) -26.7 -28.3 ± 2.0 kJ/mol 30.02653 ± 0.00087 27837-46-3*0 2-Cyclopropyn-1-ylidenemethyl anion [CC(CC)]- (g) 800.8 809.8 ± 1.7 kJ/mol 48.0433 ± 0.0032 289679-90-9*0 Propionaldehyde CH3CH2CHO (cr,l) -217.91 -216.45 ± 0.24 kJ/mol 58.0791 ± 0.0025 123-38-6*500 Ethyl nitrite CH3CH2ONO (g) -81.14 -98.54 ± 0.87 kJ/mol 75.0666 ± 0.0017 109-95-5*0 trans-1,2-Dibromoethene CHBrCHBr (g, trans) 121.6 101.8 ± 2.0 kJ/mol 185.8453 ± 0.0026 590-12-5*0 1,1-Dibromoethene CH2CBr2 (g) 125.5 105.2 ± 2.1 kJ/mol 185.8453 ± 0.0026 593-92-0*0 Monoammonium succinate (CH2C(O)OH)2(NH3) (cr) -1067.86 ± 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 1-Cyclopropene-1,2-diyl CH2(CC) (g) 791.2 790.7 ± 1.5 kJ/mol 38.0480 ± 0.0024 202744-75-0*0 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 Formaldehyde CH2O (g, triplet) 196.010 192.707 ± 0.095 kJ/mol 30.02598 ± 0.00087 50-00-0*1 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 Triiodine cation [I3]+ (g) 946.1 941.0 ± 4.1 kJ/mol 380.712861 ± 0.000090 12596-32-6*0 Ethenedione cation [OCCO]+ (g) 909.5 912.6 ± 2.0 kJ/mol 56.0197 ± 0.0017 12541-99-0*0 Hydroxyoxoammoniumyl [HONO]+ (g) 984.1 977.7 ± 1.8 kJ/mol 47.01293 ± 0.00061 80371-48-8*0 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) 518.40 521.39 ± 0.76 kJ/mol 37.0406 ± 0.0024 136861-42-2*0 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 Methylammoniumyl [CH3NH2]+ (g) 866.00 852.06 ± 0.25 kJ/mol 31.05659 ± 0.00088 34516-31-9*0 1-Cyanovinylium [CH2CCN]+ (g) 1318.4 1317.1 ± 2.2 kJ/mol 52.0542 ± 0.0024 85399-09-3*0 Hydrogen bromide HBr (aq, 600 H2O) -120.01 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*834 Dinitrogen pentoxide O2NONO2 (cr,l) -41.15 ± 0.38 kJ/mol 108.0105 ± 0.0015 10102-03-1*500 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 Hydrogen chloride HCl (aq, 1500 H2O) -166.634 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*840 Hydroperoxyimidogen HOON (g, trans) 103.3 99.8 ± 2.4 kJ/mol 47.01348 ± 0.00061 877456-58-1*1 Bicyclo[1.1.0]but-3-ene CH2(CCH)CH (g) 483.3 474.3 ± 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 Tetrahedrane cation [CH(CH(CHCH))]+ (g) 1326.8 1318.7 ± 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 Nitric acid cation [HON(O)O]+ (g) 1029.18 1020.11 ± 0.69 kJ/mol 63.01233 ± 0.00091 272109-63-4*0 Phenyl hydroperoxide C6H5OOH (g) 13.7 -5.4 ± 2.1 kJ/mol 110.1106 ± 0.0049 36112-26-2*0 Methylcyclopentadienyl CH3C(CHCHCHCH) (g) 238.9 221.3 ± 2.1 kJ/mol 79.1198 ± 0.0048 72348-44-8*0 Methylcyclopentane CH3CH(CH2CH2CH2CH2) (cr,l) -116.54 -137.90 ± 0.35 kJ/mol 84.1595 ± 0.0049 96-37-7*500 Methylamine anion [CH3NH2]- (g) 84.2 69.4 ± 2.8 kJ/mol 31.05769 ± 0.00088 81096-79-9*0 Dioxosilane SiO2 (cr, cristobalite) -904.06 -908.92 ± 0.68 kJ/mol 60.08430 ± 0.00067 7631-86-9*510 2-Butynylium [CH3CCCH2]+ (g, triplet) 1258.8 1251.5 ± 1.6 kJ/mol 53.0820 ± 0.0032 64235-83-2*1 Nirous oxide anion [NNO]- (g) 99.3 96.7 ± 1.9 kJ/mol 44.01343 ± 0.00033 12274-12-3*0 Fluorosilylidyne SiF (g) -60.26 -58.43 ± 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 1-Methylene-2-propenylium [CH2CHCCH2]+ (g, singlet) 1059.5 1049.4 ± 1.7 kJ/mol 53.0820 ± 0.0032 62698-26-4*2 Ethanium [C2H7]+ (g, classical Cs I) 888.8 870.3 ± 1.8 kJ/mol 31.0764 ± 0.0017 24669-33-8*2 1-Methylene-2-propenylium [CH2CHCCH2]+ (g, triplet) 1256.4 1246.7 ± 1.7 kJ/mol 53.0820 ± 0.0032 62698-26-4*1 Silylene anion [SiH2]- (g) 167.2 165.6 ± 1.4 kJ/mol 30.10193 ± 0.00033 54991-62-7*0 Silyliumylidene [SiH]+ (g) 1136.50 1137.70 ± 0.80 kJ/mol 29.09289 ± 0.00031 31241-66-4*0 Ethanium [C2H7]+ (g, classical Cs II) 895.2 877.3 ± 1.9 kJ/mol 31.0764 ± 0.0017 24669-33-8*3 Disilene cation [SiH2SiH2]+ (g) 1069.4 1060.4 ± 2.0 kJ/mol 60.20221 ± 0.00066 108492-63-3*0 Di-mu-hydrodihydrodisilicon cation [HSi(HSiHH)]+ (g, trans) 1180.2 1172.7 ± 3.2 kJ/mol 60.20221 ± 0.00066 *129970-82-7*1 Di-mu-hydrodihydrodisilicon anion [HSi(HSiHH)]- (g, trans) 288.5 279.9 ± 3.3 kJ/mol 60.20331 ± 0.00066 *129970-83-8*1 mu-Hydrotrihydrodisilicon Si(HSiH3) (g, triplet) 459.1 450.9 ± 2.5 kJ/mol 60.20276 ± 0.00066 497967-55-2*1 Vinylsilane CH2CHSiH3 (g) 107.9 92.5 ± 2.2 kJ/mol 58.1545 ± 0.0017 7291-09-0*0 Hydrogen bromide HBr (aq, 1250 H2O) -120.14 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*954 Dewar benzene (CHCH)(CHCHCHCH) (g) 422.2 405.1 ± 1.7 kJ/mol 78.1118 ± 0.0048 5649-95-6*0 Nitric acid HON(O)O (aq, 1 H2O) -186.82 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*801 1,3-Butadienylium [CH2CHCHCH]+ (g, singlet) 1133.7 1123.7 ± 2.5 kJ/mol 53.0820 ± 0.0032 86181-69-3*2 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) 362.6 350.0 ± 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 Hydrogen bromide HBr (aq, 5000 H2O) -120.31 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*844 Ethylaminylium [CH3CH2NH]+ (g, syn-triplet) 1092.4 1076.4 ± 2.4 kJ/mol 44.0752 ± 0.0017 54387-08-5*11 2-Methyl-2-propanamine (CH3)3CNH2 (cr,l) -133.11 -150.60 ± 0.53 kJ/mol 73.1369 ± 0.0033 75-64-9*500 1,2-Diphenylethane C6H5CH2CH2C6H5 (cr,l) 84.80 51.06 ± 0.75 kJ/mol 182.2610 ± 0.0112 103-29-7*500 Nitric acid HON(O)O (aq, 3 H2O) -197.76 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*805 Anthracene C6H4(CH(CC(C4H4)CH)) (cr,l) 150.67 124.87 ± 0.88 kJ/mol 178.2292 ± 0.0112 120-12-7*500 Phenanthrene C6H4(C2H2(CC(C4H4))) (cr,l) 136.31 111.03 ± 0.64 kJ/mol 178.2292 ± 0.0112 85-01-8*500 Diphenylacetylene C6H5CCC6H5 (g) 432.3 407.3 ± 1.2 kJ/mol 178.2292 ± 0.0112 501-65-5*0 Diphenylacetylene C6H5CCC6H5 (cr,l) 334.67 312.72 ± 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 Ethylene anion [CH2CH2]- (g, syn ?) 231.6 225.5 ± 2.0 kJ/mol 28.0537 ± 0.0016 34527-91-8*2 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 iso-Proplylide [CH3CHCH3]- (g) 128.8 110.4 ± 1.5 kJ/mol 43.0882 ± 0.0024 25012-80-0*0 Propylene cation [CH3CHCH2]+ (g) 975.20 961.67 ± 0.18 kJ/mol 42.0792 ± 0.0024 34504-10-4*0 Argonium [ArH]+ (g) 1151.8 1150.1 ± 1.4 kJ/mol 40.9554 ± 0.0010 12254-68-1*0 Xenonium [XeH]+ (g) 1038.19 1036.42 ± 0.88 kJ/mol 132.2974 ± 0.0200 37276-91-8*0 Difluoronitrate [NF2]- (g) -70.7 -72.6 ± 1.9 kJ/mol 52.004095 ± 0.000070 37366-64-6*0 Monosulfur anion S- (g) 76.42 78.48 ± 0.14 kJ/mol 32.0665 ± 0.0060 14337-03-2*0 Sulfur dioxide OSO (aq, undissoc) -320.69 ± 0.14 kJ/mol 64.0648 ± 0.0060 7446-09-5*1000 Trioxidanylium [HOOO]+ (g) 1070.7 1064.5 ± 1.4 kJ/mol 49.00559 ± 0.00090 74241-49-9*0 Sulfur oxide peroxide OSOO (g, cis) -26.0 -30.2 ± 2.3 kJ/mol 80.0642 ± 0.0061 175799-68-5*2 Hydrogen chloride HCl (aq, 1000 H2O) -166.562 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*839 Sulfuric acid OS(O)(OH)2 (aq, 115 H2O) -887.70 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*893 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 Fluoronium [HFH]+ (g) 774.04 771.10 ± 0.91 kJ/mol 21.01373 ± 0.00014 12206-67-6*0 Cyclopentene CH2(CH2CHCHCH2) (l) 7.34 ± 0.48 kJ/mol 68.1170 ± 0.0040 142-29-0*590 1-Ethylium-1-yl [CH3CH]+ (g) 1182.0 1174.7 ± 3.2 kJ/mol 28.0526 ± 0.0016 85944-79-2*0 Sulfur tetraoxide OS(O)(O)O (g, singlet Td) -163.7 -169.5 ± 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 Hydrogen chloride HCl (aq, 1250 H2O) -166.603 ± 0.024 kJ/mol 36.46064 ± 0.00090 7647-01-0*954 Methanethiol CH3SH (cr,l) -46.75 -44.57 ± 0.44 kJ/mol 48.1085 ± 0.0061 74-93-1*500 Ethylidene anion [CH3CH]- (g) 325.7 318.4 ± 1.8 kJ/mol 28.0537 ± 0.0016 35829-99-3*0 Hydroxydimethylsulfur CH3S(OH)CH3 (g) -19.7 -37.7 ± 2.6 kJ/mol 79.1424 ± 0.0062 52670-37-8*0 Carbon disulfide SCS (cr,l) 78.26 89.06 ± 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 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 Dioxygen difluoride OOF2 (g) 75.1 71.7 ± 3.6 kJ/mol 69.99561 ± 0.00060 183051-89-0*0 Vinylcyclopentadienylium [CH2CHC(CHCHCHCH)]+ (g, singlet) 1076.8 1059.4 ± 3.7 kJ/mol 91.1299 ± 0.0056 146893-89-2*2 Carbon dication [C]+2 (g) 4150.469 4155.616 ± 0.040 kJ/mol 12.00960 ± 0.00080 16092-61-8*0 Formyloxidanyl HC(O)O (g) -125.79 -127.15 ± 0.55 kJ/mol 45.0174 ± 0.0010 16499-21-1*0 Dioxiranyl HC(OO) (g) 217.3 213.8 ± 2.0 kJ/mol 45.0174 ± 0.0010 120595-16-6*0 Diethyl ether CH3CH2OCH2CH3 (cr,l) -265.28 -277.60 ± 0.75 kJ/mol 74.1216 ± 0.0033 60-29-7*500 1-Propenylium [CH3CHCH]+ (g, cis) 1231.9 1221.6 ± 1.7 kJ/mol 41.0713 ± 0.0024 50457-58-4*2 Isoprene CH2C(CH3)CHCH2 (cr,l) 48.98 ± 0.69 kJ/mol 68.1170 ± 0.0040 78-79-5*500 1-Butanol CH3CH2CH2CH2OH (cr,l) -312.82 -327.11 ± 0.21 kJ/mol 74.1216 ± 0.0033 71-36-3*500 2-Methyl-2-propanol (CH3)3COH (g) -282.0 -312.2 ± 1.9 kJ/mol 74.1216 ± 0.0033 75-65-0*0 1-Propenylide [CH3CHCH]- (g, cis) 204.0 192.7 ± 1.8 kJ/mol 41.0723 ± 0.0024 65887-20-9*2 Dioxohydrazine ONNO (g) 172.91 171.15 ± 0.14 kJ/mol 60.01228 ± 0.00062 16824-89-8*0 Nitrogen atom dianion [N]-2 (g) 1062.8 1065.0 ± 2.8 kJ/mol 14.007837 ± 0.000070 16727-21-2*0 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) -290.5 -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 Trioxirane O(OO) (g) 272.5 269.9 ± 1.3 kJ/mol 47.99820 ± 0.00090 153851-84-4*0 Hydrogen iodide HI (aq) -56.827 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*800 Methyl acetate CH3C(O)OCH3 (l) -445.61 ± 0.56 kJ/mol 74.0785 ± 0.0025 79-20-9*500 Hydrogen difluoride cation [FHF]+ (g, triplet ?) 1241. 1238. ± 17. kJ/mol 39.004198 ± 0.000070 126950-54-7*1 Ammonium hydroxide NH4OH (aq, 100000 H2O) -365.86 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*861 1-Hydroxy-2-propanone CH3C(O)CH2OH (g, anti-anti) -340.6 -360.3 ± 1.7 kJ/mol 74.0785 ± 0.0025 116-09-6*21 1-Hydroxy-2-propanone CH3C(O)CH2OH (g, gauche-anti) -338.0 -356.2 ± 1.7 kJ/mol 74.0785 ± 0.0025 116-09-6*31 1-Hydroxy-2-propanone CH3C(O)CH2OH (g, anti-syn) -329.7 -349.6 ± 1.7 kJ/mol 74.0785 ± 0.0025 116-09-6*22 Methoxyoxomethyl CH3OCO (g, syn-staggered) -151.7 -160.7 ± 1.5 kJ/mol 59.0440 ± 0.0017 16481-04-2*2 Acetonitrile CH3CN (cr,l) 40.63 ± 0.22 kJ/mol 41.0520 ± 0.0016 75-05-8*500 Propionic acid CH3CH2C(O)OH (cr,l) -505.38 -509.52 ± 0.17 kJ/mol 74.0785 ± 0.0025 79-09-4*500 Ethylene glycol (CH2OH)2 (cr,l) -448.63 -455.15 ± 0.37 kJ/mol 62.0678 ± 0.0018 107-21-1*500 Trifluorine F3 (g) 80.9 82.1 ± 2.5 kJ/mol 56.9952096 ± 0.0000015 73455-86-4*0 Deuterium hydride HD (g) 0.328 0.319 ± 0.000 kJ/mol 3.022042 ± 0.000070 13983-20-5*0 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 ± 0.58 kJ/mol 45.0837 ± 0.0017 124-40-3*500 Dihydrogen fluoride (HF)(H) (g) -56.5 -54.2 ± 1.7 kJ/mol 21.01428 ± 0.00014 12592-22-2*2 Azide [NNN]- (aq) 272.69 ± 0.47 kJ/mol 42.02077 ± 0.00021 14343-69-2*800 Dihydrogen cation [H2]+ (g, ortho) 1489.060 1488.480 ± 0.000 kJ/mol 2.01533 ± 0.00014 12184-90-6*1 (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 Carbonate [OC(O)O]-2 (g) -225.2 -228.4 ± 2.5 kJ/mol 60.0100 ± 0.0012 3812-32-6*0 N-Methylenemethaniminium [CH2NCH2]+ (g, singlet) 904.4 893.4 ± 3.1 kJ/mol 42.0594 ± 0.0016 88333-01-1*2 (Methylimino)methanide [CH3NCH]- (g, trans) 223.0 212.2 ± 3.2 kJ/mol 42.0604 ± 0.0016 *64709-60-0*1 2-Aminoethenylium [CHCHNH2]+ (g, anti triplet) 1110.6 1099.5 ± 2.4 kJ/mol 42.0594 ± 0.0016 64724-21-6*12 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) 92.34 ± 0.86 kJ/mol 43.0678 ± 0.0016 151-56-4*500 Chlorodioxidanyl ClOO (g) 100.36 99.27 ± 0.34 kJ/mol 67.4515 ± 0.0011 17376-09-9*0 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 1293.2 ± 4.1 kJ/mol 42.0594 ± 0.0016 *91127-35-4*12 Trimethylamine (CH3)3N (l) -48.27 ± 0.89 kJ/mol 59.1103 ± 0.0025 75-50-3*500 Nitric acid monohydrate (HON(O)O)(H2O) (cr,l) -479.12 -472.62 ± 0.18 kJ/mol 81.0282 ± 0.0012 13444-82-1*500 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 Peroxynitrous acid HOONO (g) -5.74 -11.57 ± 0.35 kJ/mol 63.01288 ± 0.00091 14691-52-2*0 Methoxymethylene CH3OCH (g, syn singlet) 144.8 134.4 ± 1.4 kJ/mol 44.0526 ± 0.0017 19527-10-7*22 Cyanoaminyliumyl [NCN]+ (g) 1672.4 1673.7 ± 2.6 kJ/mol 40.02363 ± 0.00081 316122-03-9*0 Cyanoamidogen anion [NCN]- (g) 211.87 211.79 ± 0.60 kJ/mol 40.02473 ± 0.00081 189879-95-6*0 Cyanoaminylium [HNCN]+ (g, singlet) 1460.2 1458.0 ± 1.9 kJ/mol 41.03157 ± 0.00082 205443-18-1*2 Diazomethanide [HCNN]- (g, triplet) 479.7 478.3 ± 1.8 kJ/mol 41.03267 ± 0.00082 100840-43-5*1 Carbon dioxide anion [CO2]- (g) -340.6 -340.1 ± 2.2 kJ/mol 44.01005 ± 0.00100 14485-07-5*0 Dioxiranylidene cation [C(OO)]+ (g) 1409.1 1410.3 ± 2.6 kJ/mol 44.00895 ± 0.00100 *138832-57-2*0 Tetrafluorohydrazine cation [NF2NF2]+ (g, trans) 1129.2 1122.5 ± 2.5 kJ/mol 104.00654 ± 0.00014 37366-75-9*1 Hydroxylamine NH2OH (aq, undissoc) -97.1 ± 2.2 kJ/mol 33.02996 ± 0.00037 7803-49-8*1000 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) 655.2 652.1 ± 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 Cyanamide NH2CN (cr) 59.04 ± 0.52 kJ/mol 42.04006 ± 0.00082 420-04-2*500 Hydrogen peroxide HOOH (cr,l) -193.109 -187.292 ± 0.077 kJ/mol 34.01468 ± 0.00062 7722-84-1*500 Carbon dioxide CO2 (aq, undissoc) -412.868 ± 0.018 kJ/mol 44.00950 ± 0.00100 124-38-9*1000 Dioxiranylidene anion [C(OO)]- (g, ?) -110.2 -109.7 ± 3.0 kJ/mol 44.01005 ± 0.00100 *138832-58-3*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) 1251.7 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 Ethynylaminylium [HCCNH]+ (g, triplet) 1277.8 1277.4 ± 2.6 kJ/mol 40.0435 ± 0.0016 103835-08-1*1 Tetrafluorohydrazine NF2NF2 (g) -13.4 -22.5 ± 1.4 kJ/mol 104.00709 ± 0.00014 10036-47-2*0 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 2-Hydroxyethenyl CHCHOH (g, cis-cis) 143.84 137.28 ± 0.99 kJ/mol 43.0446 ± 0.0016 108665-16-3*11 2-Hydroxyethenyl CHCHOH (g, trans-trans) 147.2 140.9 ± 1.2 kJ/mol 43.0446 ± 0.0016 108665-16-3*22 2-Hydroxyethenyl CHCHOH (g, cis-trans) 150.6 144.5 ± 1.6 kJ/mol 43.0446 ± 0.0016 108665-16-3*12 Hydrochlorate ion [HCl]- (g) -25.2 -24.2 ± 2.5 kJ/mol 36.46119 ± 0.00090 63099-75-2*0 Iodine monochloride ICl (cr) -36.511 -35.537 ± 0.063 kJ/mol 162.35717 ± 0.00090 7790-99-0*510 Isocyanic fluoride FNC (g) 300.9 302.7 ± 1.8 kJ/mol 45.01584 ± 0.00080 16992-26-0*0 Dioxymethylidyne cation [COO]+ (g, doublet) 1436.6 1439.0 ± 2.7 kJ/mol 44.00895 ± 0.00100 *791121-04-5*2 1-Propynylium [CH3CC]+ (g) 1547.1 1545.1 ± 3.1 kJ/mol 39.0554 ± 0.0024 24858-94-4*0 Dioxymethylidyne cation [(C)(OO)]+ (g, vdW quartet) 1388.2 1391.7 ± 3.2 kJ/mol 44.00895 ± 0.00100 *791121-04-5*101 Carbon dioxide cation [CO2]+ (g, quartet) 1335.0 1335.5 ± 2.4 kJ/mol 44.00895 ± 0.00100 12181-61-2*1 Carbon monoxide anion [CO]- (g) 30.0 33.7 ± 2.3 kJ/mol 28.01065 ± 0.00085 12539-63-8*0 Carbon monoxide CO (g, triplet) 465.583 469.290 ± 0.026 kJ/mol 28.01010 ± 0.00085 630-08-0*1 Chlorine chlorite ClOClO (g, cis) 177.4 175.1 ± 2.2 kJ/mol 102.9042 ± 0.0019 105206-44-8*2 Poly(vinylchloride) CH2CHCl (s, poly) -84.6 -94.0 ± 1.3 kJ/mol 62.4979 ± 0.0018 9002-86-2*500 Cycloprop-1-enylium [CH2(CHC)]+ (g) 1502.3 1498.0 ± 2.2 kJ/mol 39.0554 ± 0.0024 117067-78-4*0 1-Ethenylium-1-yl [CCH2]+ (g) 1507.1 1507.1 ± 2.1 kJ/mol 26.0367 ± 0.0016 80541-07-7*0 1,1-Dichloroethene CH2CCl2 (l) -23.45 ± 0.51 kJ/mol 96.9427 ± 0.0024 75-35-4*500 Oxygen difluoride anion [FOF]- (g) -202.1 -201.9 ± 2.7 kJ/mol 53.99675 ± 0.00030 *7783-41-7*0 Isocyanogen chloride ClNC (g) 314.7 316.3 ± 2.4 kJ/mol 61.4701 ± 0.0012 75754-69-7*0 Hydrogen difluoride cation [(HF)(F)]+ (g, triplet) 1267.6 1265.4 ± 4.1 kJ/mol 39.004198 ± 0.000070 *126950-54-7*1 Cycloprop-2-enylide [CH(CHCH)]- (g) 514.9 511.9 ± 2.2 kJ/mol 39.0565 ± 0.0024 20829-57-6*0 Dichloromethane CH2Cl2 (l) -122.77 ± 0.37 kJ/mol 84.9320 ± 0.0020 75-09-2*590 Trifluoroammoniumyl [NF3]+ (g) 1093.4 1087.3 ± 2.3 kJ/mol 71.001401 ± 0.000070 54384-83-7*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 Hydrazine NH2NH2 (cr,l) 57.30 50.74 ± 0.18 kJ/mol 32.04524 ± 0.00031 302-01-2*500 1-Methyl-1-ethylium-1-yl [CH3CCH3]+ (g) 1058.3 1045.8 ± 1.9 kJ/mol 42.0792 ± 0.0024 121408-19-3*0 Ethynylene C2 (g, triplet) 827.222 833.927 ± 0.085 kJ/mol 24.0214 ± 0.0016 12070-15-4*1 Tribromofluoromethane CBr3F (g) -98.9 -122.9 ± 1.5 kJ/mol 270.7211 ± 0.0031 353-54-8*0 Tribromochloromethane CBr3Cl (g) 85.7 62.9 ± 1.5 kJ/mol 287.1754 ± 0.0032 594-15-0*0 Difluoromethylene anion [CF2]- (g) -211.14 -209.96 ± 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 Trichlorine Cl3 (g) 125.3 125.8 ± 2.0 kJ/mol 106.3581 ± 0.0027 11094-65-8*0 1,3-Propanediyl CH2CH2CH2 (g, triplet C2) 320.3 308.5 ± 1.5 kJ/mol 42.0797 ± 0.0024 32458-33-6*12 Peroxyhypochlorite [ClOO]- (g) -252.78 -251.75 ± 0.34 kJ/mol 67.4520 ± 0.0011 224299-14-3*0 Isocyanogen bromide BrNC (g) 341.2 335.5 ± 3.5 kJ/mol 105.9214 ± 0.0013 65997-98-0*0 1,2-Propadien-1-ylium-1-yl-3-ylidene [CCC]+ (g, lin) 1957.20 1965.07 ± 0.82 kJ/mol 36.0316 ± 0.0024 118090-85-0*1 Difluorovinylidene CCF2 (g) 129.4 130.6 ± 2.2 kJ/mol 62.0182 ± 0.0016 41895-33-4*0 Fluoroethynylium [CCF]+ (g) 1536.3 1541.0 ± 2.3 kJ/mol 43.0193 ± 0.0016 268566-69-4*0 Bromoacetylene HCCBr (g) 282.0 275.5 ± 1.6 kJ/mol 104.9333 ± 0.0019 593-61-3*0 Dihydrogen H2 (g, ortho) 1.417 0.019 ± 0.000 kJ/mol 2.01588 ± 0.00014 1333-74-0*1 Cyclopropenylidene anion [C(CHCH)]- (g) 544.3 543.9 ± 2.2 kJ/mol 38.0485 ± 0.0024 *16165-40-5*0 n-Heptane CH3(CH2)5CH3 (cr,l) -201.47 -223.93 ± 0.44 kJ/mol 100.2019 ± 0.0057 142-82-5*500 Chloro(chlorooxy)methylene ClCOCl (g, trans singlet) 98. 101. ± 15. kJ/mol 98.9155 ± 0.0020 479587-31-0*11 Chlorooxomethylium [ClCO]+ (g) 783.7 783.8 ± 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) 1440.24 1442.10 ± 0.56 kJ/mol 50.0581 ± 0.0032 55468-55-8*0 Tetrazete N(NNN) (g, D2h) 764.9 759.0 ± 1.8 kJ/mol 56.02696 ± 0.00028 42851-09-2*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 Triiodine I3 (g) 153.4 149.4 ± 3.6 kJ/mol 380.713410 ± 0.000090 12596-31-5*0 Benzene anion [C6H6]- (g) 209.2 197.3 ± 1.2 kJ/mol 78.1124 ± 0.0048 34562-85-1*0 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 (Z)-Diazene anion [HNNH]- (g, cis) 280.0 273.3 ± 2.0 kJ/mol 30.02991 ± 0.00020 *86631-37-0*0 o-Benzyne C6H4 (g, triplet) 625.8 616.4 ± 1.1 kJ/mol 76.0960 ± 0.0048 462-80-6*1 Ammonium hydroxide NH4OH (aq, 10000 H2O) -366.25 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*850 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 Toluene C6H5CH3 (l) 19.77 12.02 ± 0.31 kJ/mol 92.1384 ± 0.0056 108-88-3*500 Tetraazatetrahedrane N(N(N)N) (g, Td) 763.7 757.3 ± 1.7 kJ/mol 56.02696 ± 0.00028 12596-63-3*0 Cyclopentadienylium [CH(CHCHCHCH)]+ (g) 1088.55 1075.68 ± 0.85 kJ/mol 65.0927 ± 0.0040 29661-18-5*0 Hydroxyoxoammoniumyl [HONO]+ (g, trans) 984.1 977.7 ± 1.8 kJ/mol 47.01293 ± 0.00061 80371-48-8*1 Ammonium hydroxide NH4OH (aq, 1 H2O) -363.82 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*801 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) 154.35 145.57 ± 0.93 kJ/mol 92.1384 ± 0.0056 544-25-2*500 Ammonia anion [NH3]- (g) 94.3 87.3 ± 2.4 kJ/mol 17.03111 ± 0.00022 37353-00-7*0 n-Octane CH3(CH2)6CH3 (cr,l) -226.30 -249.42 ± 0.52 kJ/mol 114.2285 ± 0.0065 111-65-9*500 Phenylethene C6H5CHCH2 (cr,l) 104.49 ± 0.47 kJ/mol 104.1491 ± 0.0064 100-42-5*500 Benzonitrile C6H5CN (cr,l) 161.18 163.54 ± 0.90 kJ/mol 103.1213 ± 0.0056 100-47-0*500 Isocyanobenzene C6H5NC (g) 320.9 307.1 ± 1.7 kJ/mol 103.1213 ± 0.0056 931-54-4*0 Phenol C6H5OH (cr,l) -146.19 -162.04 ± 0.65 kJ/mol 94.1112 ± 0.0048 108-95-2*500 Peroxyhypochlorous acid cation [HOOCl]+ (g, trans) 1030.4 1024.5 ± 2.5 kJ/mol 68.4589 ± 0.0011 *67952-07-2*1 Anisole C6H5OCH3 (l) -117.45 ± 0.62 kJ/mol 108.1378 ± 0.0056 100-66-3*500 Benzaldehyde C6H5C(O)H (cr,l) -85.60 -86.67 ± 0.90 kJ/mol 106.1219 ± 0.0056 100-52-7*500 Ammonium hydroxide NH4OH (aq, 2 H2O) -364.67 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*803 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 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 ± 2.1 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 Peroxyhypochlorous acid anion [HOOCl]- (g, cis quartet) -32.2 -33.9 ± 2.6 kJ/mol 68.4600 ± 0.0011 *67952-08-3*2 o-Tolualdehyde CH3C6H4C(O)H (cr, l, ortho) -118.9 ± 1.1 kJ/mol 120.1485 ± 0.0064 529-20-4*500 Methanol dimer (CH3OH)2 (g) -398.2 -418.9 ± 1.4 kJ/mol 64.0837 ± 0.0018 42845-44-3*0 Fluorobenzene anion [C6H5F]- (g) -15.3 -27.1 ± 1.6 kJ/mol 96.1029 ± 0.0048 34561-55-2*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 Bicyclo[1.1.0]buta-1,3-dien-2-yl anion [C(CC)C]- (g) 803.1 810.8 ± 1.8 kJ/mol 48.0433 ± 0.0032 289679-89-6*0 Hexafluorobenzene anion [C6F6]- (g) -992.7 -995.0 ± 3.5 kJ/mol 186.0552 ± 0.0048 37551-90-9*0 m-Chlorophenylium [C6H4Cl]+ (g) 1161.6 1151.5 ± 2.6 kJ/mol 111.5481 ± 0.0049 127983-85-1*0 p-Chlorophenylium [C6H4Cl]+ (g) 1148.9 1139.4 ± 2.5 kJ/mol 111.5481 ± 0.0049 42766-43-8*0 1,3-Butadiynyl anion [CCCC]- (g) 677.2 686.4 ± 1.1 kJ/mol 48.0433 ± 0.0032 59158-53-1*0 o-Chlorophenylium [C6H4Cl]+ (g) 1168.2 1158.9 ± 2.5 kJ/mol 111.5481 ± 0.0049 137963-70-3*0 Iodobenzene cation [C6H5I]+ (g) 1023.58 1008.14 ± 0.99 kJ/mol 204.0078 ± 0.0048 38406-85-8*0 Ammonium hydroxide NH4OH (aq, 3 H2O) -365.13 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*805 Oxoethylidene anion [HCC(O)H]- (g, anti-gauche) 86.9 83.6 ± 2.1 kJ/mol 42.0372 ± 0.0016 106543-38-8*1 Nitrobenzene C6H5N(O)O (cr,l) 7.2 ± 1.4 kJ/mol 123.1094 ± 0.0049 98-95-3*500 2-Cyclopropyn-1-ylidenemethyliumyl [CC(CC)]+ (g) 2239.6 2247.5 ± 2.3 kJ/mol 48.0423 ± 0.0032 289679-92-1*0 Pyridine N(CHCHCHCHCH) (cr,l) 102.23 100.20 ± 0.38 kJ/mol 79.0999 ± 0.0040 110-86-1*500 Nitromethane CH3N(O)O (cr,l) -114.10 -112.91 ± 0.40 kJ/mol 61.0401 ± 0.0010 75-52-5*500 Ammonium hydroxide NH4OH (aq, 4 H2O) -365.43 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*807 Propane cation [CH3CH2CH3]+ (g) 974.7 954.6 ± 1.7 kJ/mol 44.0951 ± 0.0025 34479-70-4*0 n-Nonane CH3(CH2)7CH3 (cr,l) -247.63 -274.49 ± 0.47 kJ/mol 128.2551 ± 0.0073 111-84-2*500 2,2,4-Trimethylpentane (CH3)2CHCH2C(CH3)3 (cr,l) -224.2 -258.7 ± 1.5 kJ/mol 114.2285 ± 0.0065 540-84-1*500 cis-1,2-Diiodoethene CHICHI (g, cis) 217.47 209.18 ± 0.35 kJ/mol 279.8462 ± 0.0016 590-26-1*0 trans-1,2-Diiodoethene CHICHI (g, trans) 215.12 207.73 ± 0.35 kJ/mol 279.8462 ± 0.0016 590-27-2*0 Norbornadiene (CHCH)(CHCH2CH)(CHCH) (l) 206.1 ± 1.6 kJ/mol 92.1384 ± 0.0056 121-46-0*500 2,3-Butanedione CH3C(O)C(O)CH3 (cr,l) -365.57 ± 0.53 kJ/mol 86.0892 ± 0.0033 431-03-8*500 Succinic acid (CH2C(O)OH)2 (g) -801.3 -823.5 ± 2.7 kJ/mol 118.0880 ± 0.0034 110-15-6*0 Oxygen difluoride cation [FOF]+ (g) 1292.10 1289.57 ± 0.66 kJ/mol 53.99566 ± 0.00030 39432-25-2*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) -267.73 -273.22 ± 0.79 kJ/mol 72.1057 ± 0.0033 78-93-3*500 Acrolein cation [CH2CHCHO]+ (g, trans) 920.01 909.87 ± 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) -95.58 ± 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 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 Nitrous acid anion [HONO]- (g, cis) -105.84 -110.46 ± 0.78 kJ/mol 47.01403 ± 0.00061 256393-36-9*2 2-Propen-3-ylium-1-ylidyne [CHCHC]+ (g) 1791.2 1792.8 ± 2.6 kJ/mol 38.0474 ± 0.0024 161054-36-0*0 Ethenedione anion [OCCO]- (g) -149.7 -147.1 ± 1.7 kJ/mol 56.0207 ± 0.0017 77783-15-4*0 Hydrogen chloride HCl (aq, 2439 H2O) -166.711 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*951 Urea NH2C(O)NH2 (cr,l) -317.73 -333.33 ± 0.12 kJ/mol 60.05534 ± 0.00091 57-13-6*500 Propenediylidene anion [CHCHC]- (g) 588.9 590.1 ± 2.3 kJ/mol 38.0485 ± 0.0024 *161054-36-0*0 Paraformaldehyde CH2O (cr, paraformaldehyde) -176.4 ± 1.5 kJ/mol 30.02598 ± 0.00087 30525-89-4*500 Formamide CH(O)NH2 (cr,l) -251.04 ± 0.28 kJ/mol 45.04066 ± 0.00088 75-12-7*500 Acetamide CH3C(O)NH2 (cr,l) -315.88 ± 0.53 kJ/mol 59.0672 ± 0.0017 60-35-5*500 Trifluoronitrate [NF3]- (g) -246.7 -248.9 ± 2.5 kJ/mol 71.002498 ± 0.000070 37366-69-1*0 Acrylonitrile CH2CHCN (g, triplet) 446.5 441.1 ± 1.7 kJ/mol 53.0627 ± 0.0024 107-13-1*2 Acrylonitrile CH2CHCN (cr,l) 146.54 154.20 ± 0.73 kJ/mol 53.0627 ± 0.0024 107-13-1*500 Bromoniumyl [HBr]+ (g) 1098.16 1090.31 ± 0.12 kJ/mol 80.9114 ± 0.0010 12258-64-9*0 Isocyanoethene CH2CHNC (g, triplet) 544.2 539.3 ± 1.8 kJ/mol 53.0627 ± 0.0024 14668-82-7*2 1-Isocyanoethylidene CH3CNC (g) 528.0 523.2 ± 1.1 kJ/mol 53.0627 ± 0.0024 *498544-34-6*0 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 n-Decane CH3(CH2)8CH3 (cr,l) -272.89 -300.43 ± 0.75 kJ/mol 142.2817 ± 0.0081 124-18-5*500 Trihydrogen H(HH) (g, 2p 2A2" Ry) 756.931 754.146 ± 0.015 kJ/mol 3.02382 ± 0.00021 12184-91-7*2 Hydroxymethoxy CH2(OH)O (g) -159.58 -169.43 ± 0.84 kJ/mol 47.0333 ± 0.0010 72144-78-6*0 Hydrazoic acid cation [HNNN]+ (g) 1333.73 1328.06 ± 0.82 kJ/mol 43.02761 ± 0.00022 58852-14-5*0 Perchloryl cation [OCl(O)O]+ (g) 1252.1 1246.4 ± 2.5 kJ/mol 83.4504 ± 0.0013 23594-88-9*0 Hydrogen fluoride HF (aq, 50 H2O) -321.95 ± 0.10 kJ/mol 20.006343 ± 0.000070 7664-39-3*822 Tetraoxygen O4 (g, C2h triplet) 104.4 102.4 ± 3.5 kJ/mol 63.9976 ± 0.0012 12596-83-7*11 Ammonium hydroxide NH4OH (aq, 10 H2O) -366.00 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*815 Vinylacetylene CH2CHCCH (cr,l) 266.5 ± 2.1 kJ/mol 52.0746 ± 0.0032 689-97-4*500 Isopropylidene anion [CH3CCH3]- (g) 282.5 268.4 ± 2.0 kJ/mol 42.0803 ± 0.0024 *121408-19-3*0 Difluorodioxidanium [FOOF]+ (g, trans) 1283.7 1279.2 ± 2.3 kJ/mol 69.99506 ± 0.00060 *7783-44-0*1 Hydrogen fluoride HF (aq, 55 H2O) -321.96 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*905 1,5-Hexadiene CH2CHCH2CH2CHCH2 (cr,l) 54.55 ± 0.31 kJ/mol 82.1436 ± 0.0049 592-42-7*500 Vinylvinylidene CH2CHCHC (g, triplet, trans) 690.5 684.5 ± 2.7 kJ/mol 52.0746 ± 0.0032 148759-16-4*11 Hydroxymethyleneoxonium [CH2OOH]+ (g) 792.94 782.80 ± 0.63 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 1-Buten-3-ynylium [HCCCHCH]+ (g, cis) 1483.2 1480.7 ± 1.7 kJ/mol 51.0661 ± 0.0032 84654-85-3*2 Cyclobutane CH2(CH2CH2CH2) (l) 3.90 ± 0.39 kJ/mol 56.1063 ± 0.0032 287-23-0*590 Nitrosyl nitrite anion [ONONO]- (g, t, t) -103.0 -106.2 ± 2.8 kJ/mol 76.01223 ± 0.00091 *122413-35-8*1 Methylcyclopropane CH3CH(CH2CH2) (l) 1.93 ± 0.59 kJ/mol 56.1063 ± 0.0032 594-11-6*590 2-Cyclopropen-1-ylidenemethylium [CHC(CHCH)]+ (g, triplet) 1433.2 1429.5 ± 1.9 kJ/mol 51.0661 ± 0.0032 112936-36-4*1 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 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 -239.33 ± 0.84 kJ/mol 72.1057 ± 0.0033 123-72-8*500 Dioxohydrazine ONNO (g, cis) 172.91 171.15 ± 0.14 kJ/mol 60.01228 ± 0.00062 16824-89-8*2 Disilicon cation [Si2]+ (g) 1349.8 1353.4 ± 2.7 kJ/mol 56.17045 ± 0.00060 12597-36-3*0 Dioxosilane cation [SiO2]+ (g) 946.2 946.2 ± 2.8 kJ/mol 60.08375 ± 0.00067 59458-81-0*0 Silicate [SiO2]- (g) -477.5 -478.3 ± 2.6 kJ/mol 60.08485 ± 0.00067 53095-83-3*0 Isodiazene anion [NNH2]- (g) 380.9 374.1 ± 2.1 kJ/mol 30.02991 ± 0.00020 *63986-30-1*0 Oxosilicate [SiO]- (g) -106.1 -104.9 ± 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, 20 H2O) -366.20 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*818 Hydrazoic acid anion [HNNN]- (g, trans) 309.1 302.8 ± 2.3 kJ/mol 43.02871 ± 0.00022 203264-98-6*1 Fluorosilylidyne anion [SiF]- (g) -139.0 -137.6 ± 1.8 kJ/mol 47.08445 ± 0.00030 11080-58-3*0 Silane cation [SiH4]+ (g) 1104.6 1097.4 ± 1.6 kJ/mol 32.11671 ± 0.00041 34826-51-2*0 Silylium [SiH3]+ (g) 989.64 984.06 ± 0.89 kJ/mol 31.10877 ± 0.00037 41753-67-7*0 Silylidyne anion [SiH]- (g) 250.0 251.2 ± 1.1 kJ/mol 29.09399 ± 0.00031 68865-96-3*0 Disilanylium [SiH3SiH2]+ (g) 981.5 970.1 ± 2.5 kJ/mol 61.21015 ± 0.00069 86860-82-4*0 Methylamine CH3NH2 (l) -45.17 ± 0.45 kJ/mol 31.05714 ± 0.00088 74-89-5*500 1-Disilanylium-1-yl [SiH3SiH]+ (g) 1124.1 1116.4 ± 2.2 kJ/mol 60.20221 ± 0.00066 108492-64-4*0 Oxobromonium [BrO]+ (g) 1140.0 1132.2 ± 1.6 kJ/mol 95.9029 ± 0.0010 142315-39-7*0 Di-mu-hydrodihydrodisilicon cation [HSi(HSiHH)]+ (g, cis) 1194.4 1184.7 ± 3.4 kJ/mol 60.20221 ± 0.00066 *129970-82-7*2 Di-mu-hydrodihydrodisilicon anion [HSi(HSiHH)]- (g, cis) 296.6 289.1 ± 3.5 kJ/mol 60.20331 ± 0.00066 *129970-83-8*2 Hydrogen fluoride HF (aq, 23 H2O) -321.85 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*903 Ammonium hydroxide NH4OH (aq, 50000 H2O) -366.02 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*855 Dihydrogen H2 (g, para) -0.000 -0.058 ± 0.000 kJ/mol 2.01588 ± 0.00014 1333-74-0*2 Oxadiazirine cation [O(NN)]+ (g) 1509.9 1507.2 ± 2.4 kJ/mol 44.01233 ± 0.00033 *227934-45-4*0 Ammonium hydroxide NH4OH (aq, 50 H2O) -366.32 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*822 1,2-Butadienylium [CH3CHCCH]+ (g, triplet) 1315.5 1307.5 ± 1.7 kJ/mol 53.0820 ± 0.0032 *65114-67-2*1 Ammonium hydroxide NH4OH (aq, 5000 H2O) -366.30 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*844 Trioxidanyl HOOO (g) 25.36 23.27 ± 0.13 kJ/mol 49.00614 ± 0.00090 12500-78-6*0 Tetraoxidanyl HOOOO (g, cis) 53.0 46.0 ± 5.1 kJ/mol 65.0055 ± 0.0012 69696-93-1*2 Dihydrogen cation [H2]+ (g, para) 1488.364 1488.480 ± 0.000 kJ/mol 2.01533 ± 0.00014 12184-90-6*2 2,4-Hexadiyne CH3CCCCCH3 (cr,l) 319.15 312.79 ± 0.97 kJ/mol 78.1118 ± 0.0048 2809-69-0*500 Tetraoxodinitrogen cation [O2NNO2]+ (g) 1030.6 1025.2 ± 2.6 kJ/mol 92.0105 ± 0.0012 64476-91-1*0 NON cation [NON]+ (g) 1444.0 1444.2 ± 2.8 kJ/mol 44.01233 ± 0.00033 *227934-46-5*0 Trimethylenecyclopropane (C3)(CH2)3 (g) 454.2 441.4 ± 1.8 kJ/mol 78.1118 ± 0.0048 3227-90-5*0 3,4-Bis(methylene)cyclobutene CH2(CCHCHC)CH2 (g) 355.6 341.0 ± 1.8 kJ/mol 78.1118 ± 0.0048 5291-90-7*0 1,3-Butadienylium [CH2CHCHCH]+ (g, triplet) 1255.9 1246.5 ± 2.3 kJ/mol 53.0820 ± 0.0032 86181-69-3*1 Ammonium hydroxide NH4OH (aq, 100 H2O) -366.36 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*828 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 NON anion [NON]- (g) 495.3 492.8 ± 2.5 kJ/mol 44.01343 ± 0.00033 *227934-47-6*0 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 1-Aminoethylium [CH3CHNH2]+ (g) 683.4 664.7 ± 2.3 kJ/mol 44.0752 ± 0.0017 *30208-36-7*0 1-Propanamine CH3CH2CH2NH2 (cr,l) -93.77 -101.38 ± 0.40 kJ/mol 59.1103 ± 0.0025 107-10-8*500 2-Propanamine CH3CH(CH3)NH2 (cr,l) -101.53 -112.14 ± 0.52 kJ/mol 59.1103 ± 0.0025 75-31-0*500 Naphthalene C6H4(C4H4) (cr,l) 94.75 75.16 ± 0.55 kJ/mol 128.1705 ± 0.0080 91-20-3*500 Ammonium hydroxide NH4OH (aq, 500 H2O) -366.38 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*833 Formic acid HC(O)OH (aq) -425.47 ± 0.45 kJ/mol 46.0254 ± 0.0010 64-18-6*800 Biphenyl C6H5C6H5 (cr,l) 121.6 97.1 ± 1.1 kJ/mol 154.2078 ± 0.0096 92-52-4*500 Biphenyl C6H5C6H5 (cr) 121.6 97.1 ± 1.1 kJ/mol 154.2078 ± 0.0096 92-52-4*520 Hydronium radical (H2O)(H) (g, vdW) -18.5 -21.5 ± 2.1 kJ/mol 19.02322 ± 0.00037 12168-76-2*100 Aniline C6H5NH2 (cr,l) 37.28 31.03 ± 0.63 kJ/mol 93.1265 ± 0.0048 62-53-3*500 Nitric acid trihydrate (HON(O)O)(H2O)3 (cr,l) -1062.01 -1055.16 ± 0.20 kJ/mol 117.0587 ± 0.0019 13444-83-2*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 Hydraziniumyl [NH2NH2]+ (g) 886.7 873.3 ± 2.0 kJ/mol 32.04469 ± 0.00031 20771-51-1*0 Pyruvic acid CH3C(O)C(O)OH (cr,l) -588.52 ± 0.74 kJ/mol 88.0621 ± 0.0026 127-17-3*500 Dioxidanyl dimer (HOO)2 (g, triplet) -8.29 -17.86 ± 0.50 kJ/mol 66.0135 ± 0.0012 240125-82-0*1 Peroxychlorous acid HOOClO (g, anti) 102.7 96.9 ± 2.4 kJ/mol 84.4588 ± 0.0013 177778-92-6*2 Sulfur trioxide OS(O)O (l) -440.87 ± 0.30 kJ/mol 80.0642 ± 0.0061 7446-11-9*590 Sulfanylium [SH]+ (g) 1148.36 1148.36 ± 0.19 kJ/mol 33.0734 ± 0.0060 12273-42-6*0 Sulfuric acid OS(O)(OH)2 (aq, 70 H2O) -887.10 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*824 Chloryl ion [OClO]+ (g) 1100.26 1097.60 ± 0.53 kJ/mol 67.4510 ± 0.0011 25052-55-5*0 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 Oxygen atom hexacation [O]+6 (g) 42035.28 42037.14 ± 0.12 kJ/mol 15.99611 ± 0.00030 14158-22-6*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 Sulfate monoanion [OS(O)(O)O]- (g) -736.9 -744.6 ± 2.2 kJ/mol 96.0641 ± 0.0061 12143-45-2*0 Bromosyl bromide BrBrO (g) 180.4 164.6 ± 2.1 kJ/mol 175.8074 ± 0.0020 68322-97-4*0 Dioxodiazoxane ONONO (g, c, p) 125.7 120.4 ± 2.1 kJ/mol 76.01168 ± 0.00091 122413-35-8*3 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 Hydrogen atom H (ad, 4 Pt(111)) -33.4 -35.1 ± 1.5 kJ/mol 1.007940 ± 0.000070 12385-13-6*1000004 Fluorine atom hexacation [F]+6 (g) 45781.5 45783.3 ± 1.8 kJ/mol 18.99511172 ± 0.00000050 14701-04-3*0 Chlorodioxidenium [ClOO]+ (g) 1215.1 1212.9 ± 6.3 kJ/mol 67.4510 ± 0.0011 64710-10-7*0 Diazomethylium [HCNN]+ (g, singlet) 1458.9 1456.8 ± 2.2 kJ/mol 41.03157 ± 0.00082 271249-81-1*2 Formylimidogen HC(O)N (g, singlet) 245.3 242.1 ± 3.3 kJ/mol 43.02478 ± 0.00086 42288-92-6*2 Ammonium oxide (NH4)2O (cr,l) -428.46 -430.46 ± 0.61 kJ/mol 52.07640 ± 0.00065 12161-77-2*500 Diazirinylium [HC(NN)]+ (g, singlet) 1384.8 1381.2 ± 2.1 kJ/mol 41.03157 ± 0.00082 77116-26-8*2 Hydroxylamine NH2OH (cr,l) -107.44 ± 0.60 kJ/mol 33.02996 ± 0.00037 7803-49-8*500 Water trimer (H2O)3 (g) -762.65 -776.75 ± 0.20 kJ/mol 54.04584 ± 0.00099 31014-12-7*0 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) 405.3 402.0 ± 2.5 kJ/mol 41.03267 ± 0.00082 150296-30-3*1 Ammonia NH3 (aq, 500 H2O) -80.58 ± 0.41 kJ/mol 17.03056 ± 0.00022 7664-41-7*833 Carbon pentacation [C]+5 (g) 52824.600 52829.746 ± 0.050 kJ/mol 12.00796 ± 0.00080 14280-11-6*0 Tetrafluorohydrazine NF2NF2 (g, gauche) -12.5 -22.1 ± 1.4 kJ/mol 104.00709 ± 0.00014 10036-47-2*2 1-Propenylium [CH3CHCH]+ (g, trans) 1233.8 1223.4 ± 2.0 kJ/mol 41.0713 ± 0.0024 50457-58-4*1 1-Propenylide [CH3CHCH]- (g, trans) 210.5 199.3 ± 2.0 kJ/mol 41.0723 ± 0.0024 65887-20-9*1 Carbon hexacation [C]+6 (g) 100101.754 100106.900 ± 0.050 kJ/mol 12.00741 ± 0.00080 16249-02-8*0 Hydrazoic acid HNNN (aq) 272.69 ± 0.47 kJ/mol 43.02816 ± 0.00022 7782-79-8*800 1-Hydroxyethenylium [CH2COH]+ (g, anti-triplet) 1025.4 1018.3 ± 2.9 kJ/mol 43.0441 ± 0.0016 41084-89-3*11 2,2-Dimethylbutane CH3CH2C(CH3)3 (cr,l) -187.92 -213.63 ± 0.75 kJ/mol 86.1754 ± 0.0049 75-83-2*500 (Iminomethyl)imidogen HNCHN (g, triplet) 420.1 413.3 ± 2.9 kJ/mol 42.04006 ± 0.00082 87570-07-8*1 Nitrosyl nitrite anion [ONONO]- (g, t, c) -100.2 -103.4 ± 2.9 kJ/mol 76.01223 ± 0.00091 *122413-35-8*2 Ethynylaminylium [HCCNH]+ (g, singlet) 1350.6 1348.8 ± 2.5 kJ/mol 40.0435 ± 0.0016 103835-08-1*2 Acetylene HCCH (g, cis-triplet) 599.2 599.0 ± 1.5 kJ/mol 26.0373 ± 0.0016 74-86-2*11 Hydrogen peroxide HOOH (g, para) -129.421 -135.407 ± 0.058 kJ/mol 34.01468 ± 0.00062 7722-84-1*2 Methylaminyliumyl [CH3N]+ (g, doublet ?) 1388.2 1381.9 ± 2.2 kJ/mol 29.04071 ± 0.00083 56924-51-7*1 Tribromine cation [Br3]+ (g) 1036.3 1013.6 ± 2.5 kJ/mol 239.7115 ± 0.0030 33105-86-1*0 Ammonia NH3 (aq, 1000 H2O) -80.57 ± 0.41 kJ/mol 17.03056 ± 0.00022 7664-41-7*839 Carbon monoxide CO (g, singlet) -113.799 -110.519 ± 0.026 kJ/mol 28.01010 ± 0.00085 630-08-0*2 Trihydrogen H(HH) (g, 2s 2A1' Ry) 745.878 743.094 ± 0.062 kJ/mol 3.02382 ± 0.00021 12184-91-7*1 Nitrogen atom anion N- (g) 488.2 490.5 ± 2.3 kJ/mol 14.007289 ± 0.000070 17778-87-9*0 Tetrabromomethane CBr4 (cr, monoclinic) 59.2 ± 1.3 kJ/mol 331.6267 ± 0.0041 558-13-4*500 Ammonium hydroxide NH4OH (aq, undissoc) -366.685 ± 0.059 kJ/mol 35.04584 ± 0.00047 1336-21-6*1000 Tetraiodomethane CI4 (cr, monoclinic) 392.5 ± 8.0 kJ/mol 519.62858 ± 0.00081 507-25-5*500 Nitrogen atom dication [N]+2 (g) 4728.997 4731.826 ± 0.024 kJ/mol 14.005643 ± 0.000070 17439-59-7*0 Bromomethane CH3Br (l) -56.25 -59.26 ± 0.21 kJ/mol 94.9385 ± 0.0013 74-83-9*590 Chlorine atom dication [Cl]+2 (g) 3668.474 3670.081 ± 0.013 kJ/mol 35.45160 ± 0.00090 15723-23-6*0 Dioxofluorine cation [OFO]+ (g) 1667.0 1664.8 ± 2.8 kJ/mol 50.99665 ± 0.00060 223566-05-0*0 Dioxofluorine anion [OFO]- (g) 155.9 154.4 ± 2.5 kJ/mol 50.99775 ± 0.00060 *175861-93-5*0 Ethynylene C2 (g, singlet) 819.999 826.571 ± 0.085 kJ/mol 24.0214 ± 0.0016 12070-15-4*2 2-Propen-1-ylium-1-ylidene [CH2CHC]+ (g) 1373.2 1369.7 ± 2.0 kJ/mol 39.0554 ± 0.0024 88000-25-3*0 Ketene CH2CO (g, para singlet) -45.33 -48.39 ± 0.11 kJ/mol 42.0367 ± 0.0016 463-51-4*21 Water H2O (cr) -286.274 -292.715 ± 0.022 kJ/mol 18.01528 ± 0.00033 7732-18-5*510 Dinitrogen dimer (N2)2 (g) -0.88 0.84 ± 0.67 kJ/mol 56.02696 ± 0.00028 154680-01-0*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 Ethyl bromide CH3CH2Br (l) -55.38 -90.91 ± 0.25 kJ/mol 108.9651 ± 0.0019 74-96-4*500 Vinyl iodide CH2CHI (g) 139.7 130.9 ± 1.2 kJ/mol 153.9497 ± 0.0016 593-66-8*0 1-Propen-1-yl-3-ylidene CHCHCH (g, quartet) 656.8 653.3 ± 1.1 kJ/mol 39.0559 ± 0.0024 84654-90-0*1 Difluorovinylidene cation [CCF2]+ (g) 1181.5 1183.0 ± 2.3 kJ/mol 62.0177 ± 0.0016 268566-71-8*0 Oxygen atom dication [O]+2 (g) 4949.458 4953.000 ± 0.013 kJ/mol 15.99830 ± 0.00030 14127-63-0*0 Carbonic acid C(O)(OH)2 (aq, undissoc) -698.670 ± 0.028 kJ/mol 62.0248 ± 0.0012 463-79-6*1000 Tribromide [Br3]- (aq) -129.17 ± 0.22 kJ/mol 239.7125 ± 0.0030 14522-80-6*800 Isocyanogen bromide anion [BrNC]- (g) 105.1 101.9 ± 4.6 kJ/mol 105.9220 ± 0.0013 *238754-53-5*0 Oxygen atom trication [O]+3 (g) 10249.929 10252.880 ± 0.018 kJ/mol 15.99775 ± 0.00030 14127-64-1*0 Chloro(chlorooxy)methylene ClCOCl (g, trans triplet) 101.1 104.7 ± 4.8 kJ/mol 98.9155 ± 0.0020 479587-31-0*12 mu-Oxodichlorate anion [ClOCl]- (g) -147.8 -147.7 ± 2.5 kJ/mol 86.9053 ± 0.0018 365546-30-1*0 Oxygen atom tetracation [O]+4 (g) 17719.207 17721.064 ± 0.025 kJ/mol 15.99721 ± 0.00030 14127-65-2*0 Dihydrogen anion [H2]- (g) 253.8 254.7 ± 1.2 kJ/mol 2.01643 ± 0.00014 12184-89-3*0 Nitrogen atom pentacation [N]+5 (g) 26226.70 26228.56 ± 0.23 kJ/mol 14.003997 ± 0.000070 20508-99-0*0 Nitrogen atom hexacation [N]+6 (g) 79493.10 79494.96 ± 0.23 kJ/mol 14.003449 ± 0.000070 15721-56-9*0 1,3,5-Hexatriynylium [CCCCCCH]+ (g, singlet) 1952.6 1961.4 ± 7.6 kJ/mol 73.0716 ± 0.0048 81932-75-4*2 Trihydrogen cation [H3]+ (g, para) 1110.304 1106.697 ± 0.013 kJ/mol 3.02327 ± 0.00021 28132-48-1*2 Carbon suboxide OCCCO (cr,l) -131.18 -116.14 ± 0.97 kJ/mol 68.0309 ± 0.0025 504-64-3*500 Methyl acetate CH3C(O)OCH3 (g) -394.15 -413.02 ± 0.56 kJ/mol 74.0785 ± 0.0025 79-20-9*0 Bromodioxy BrOO (g) 116.7 107.7 ± 3.8 kJ/mol 111.9028 ± 0.0012 67177-47-3*0 Fluorine atom octacation [F]+8 (g) 155686.5 155688.3 ± 1.8 kJ/mol 18.99401456 ± 0.00000050 15721-58-1*0 m-Benzyne C6H4 (g, triplet) 615.1 605.7 ± 1.4 kJ/mol 76.0960 ± 0.0048 1828-89-3*1 Hydrogen fluoride HF (aq, 3 H2O) -320.69 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*805 Oxygen atom heptacation [O]+7 (g) 113369.48 113371.34 ± 0.12 kJ/mol 15.99556 ± 0.00030 14274-89-6*0 Deuteride D- (g) 146.991 148.904 ± 0.0021 kJ/mol 2.01465035791 ± 0.00000000040 14452-69-8*0 4,5-Bis(methylene)-2-cyclopenten-1-yl CH(CHC(CH2)C(CH2)CH) (g) 315.2 297.0 ± 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) 320.9 302.7 ± 2.0 kJ/mol 91.1305 ± 0.0056 512782-58-0*0 Methyl formate HC(O)OCH3 (g) -346.85 -359.89 ± 0.61 kJ/mol 60.0520 ± 0.0017 107-31-3*0 Ethyl formate HC(O)OCH2CH3 (g) -375.0 -393.8 ± 1.0 kJ/mol 74.0785 ± 0.0025 109-94-4*0 Nitride [N]-3 (g) 1879.1 1881.0 ± 4.4 kJ/mol 14.008386 ± 0.000070 18851-77-9*0 Ammonia NH3 (aq, 20 H2O) -80.38 ± 0.41 kJ/mol 17.03056 ± 0.00022 7664-41-7*818 Tropylide [CH(CHCHCHCHCHCH)]- (g) 261.6 245.2 ± 2.0 kJ/mol 91.1310 ± 0.0056 34464-18-1*0 Hydrogen bromide HBr (aq, 2570 H2O) -120.24 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*952 Hydrazine monohydrate (NH2NH2)(H2O) (l) -242.58 ± 0.19 kJ/mol 50.06052 ± 0.00053 7803-57-8*500 Oxygen atom octacation [O]+8 (g) 197447.75 197449.60 ± 0.12 kJ/mol 15.99501 ± 0.00030 21450-98-6*0 Fluorine atom heptacation [F]+7 (g) 63649.3 63651.1 ± 1.8 kJ/mol 18.99456314 ± 0.00000050 14700-77-7*0 Peroxyhypochlorous acid cation [HOOCl]+ (g, cis) 1050.8 1045.2 ± 2.5 kJ/mol 68.4589 ± 0.0011 *67952-07-2*2 Cyclopropane cation [CH2(CH2CH2)]+ (g) 1021.8 1006.3 ± 1.5 kJ/mol 42.0792 ± 0.0024 34496-93-0*0 Acetoxy CH3C(O)O (g) -182.13 -190.84 ± 0.80 kJ/mol 59.0440 ± 0.0017 13799-69-4*0 Hydrogen iodide HI (aq, 5130 H2O) -56.645 ± 0.089 kJ/mol 127.912410 ± 0.000076 10034-85-2*958 Bicyclo[1.1.0]buta-1,3-diene-2,4-diyl C(CC)C (g, singlet) 1047.17 1054.76 ± 0.68 kJ/mol 48.0428 ± 0.0032 12184-80-4*2 Oxygen atom pentacation [O]+5 (g) 28708.788 28710.645 ± 0.053 kJ/mol 15.99666 ± 0.00030 14127-66-3*0 1,3-Butadiyn-4-ylium-1-yl [CCCC]+ (g) 2109.9 2120.5 ± 2.8 kJ/mol 48.0423 ± 0.0032 124708-46-9*0 2-Methylpentane CH3CH2CH2CH(CH3)2 (cr,l) -180.16 -203.82 ± 0.73 kJ/mol 86.1754 ± 0.0049 107-83-5*500 Ammonia NH3 (aq) -77.032 ± 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 1,3-Butadiyne-1,4-diyl CCCC (g, triplet) 1052.27 1062.24 ± 0.64 kJ/mol 48.0428 ± 0.0032 78015-07-3*1 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 Hydroxyoxoammoniumyl [HONO]+ (g, cis) 1014.8 1008.4 ± 2.0 kJ/mol 47.01293 ± 0.00061 80371-48-8*2 Carbon trication [C]+3 (g) 8770.938 8776.084 ± 0.047 kJ/mol 12.00905 ± 0.00080 14067-06-2*0 Oxoethylidene anion [HCC(O)H]- (g, syn-gauche) 92.3 89.0 ± 2.3 kJ/mol 42.0372 ± 0.0016 106543-38-8*2 Carbide [C]-4 (g) 2709.5 2714.7 ± 2.7 kJ/mol 12.01289 ± 0.00080 12385-15-8*0 Chlorine atom trication [Cl]+3 (g) 7487.2 7490.2 ± 3.3 kJ/mol 35.45105 ± 0.00090 16547-50-5*0 Propionic acid CH3CH2C(O)OH (g) -435.91 -453.79 ± 0.60 kJ/mol 74.0785 ± 0.0025 79-09-4*0 3-Methylpentane CH3CH2CH(CH3)CH2CH3 (cr,l) -177.61 -201.88 ± 0.76 kJ/mol 86.1754 ± 0.0049 96-14-0*500 Nitrosyl nitrate ONONO2 (g, cis-perp) 60.4 52.5 ± 1.9 kJ/mol 92.0111 ± 0.0012 15969-55-8*2 1-Methylethenylium [CH3CCH2]+ (g) 995.2 986.0 ± 1.9 kJ/mol 41.0713 ± 0.0024 50457-57-3*0 Ammonia NH3 (aq, 2 H2O) -78.02 ± 0.41 kJ/mol 17.03056 ± 0.00022 7664-41-7*803 Trioxirane cation [O(OO)]+ (g) 1444.4 1442.2 ± 2.2 kJ/mol 47.99765 ± 0.00090 *153851-84-4*0 Succinic acid (CH2C(O)OH)2 (cr,l) -918.49 -940.22 ± 0.12 kJ/mol 118.0880 ± 0.0034 110-15-6*500 Propylidene CH3CH2CH (g, triplet) 349.51 335.75 ± 0.92 kJ/mol 42.0797 ± 0.0024 6700-78-3*1 Formaldehyde CH2O (g, para singlet) -105.381 -109.221 ± 0.095 kJ/mol 30.02598 ± 0.00087 50-00-0*21 1,2-Dibromoethane CH2BrCH2Br (cr,l) -80.1 ± 1.2 kJ/mol 187.8612 ± 0.0026 106-93-4*500 Chlorine trifluoride cation [FCl(F)F]+ (g) 1053.5 1049.2 ± 2.3 kJ/mol 92.44736 ± 0.00090 478167-77-0*0 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 Chlorine atom tetracation [Cl]+4 (g) 12615.5 12617.1 ± 4.6 kJ/mol 35.45051 ± 0.00090 22541-74-8*0 Fluorine atom dication [F]+2 (g) 5132.472 5134.256 ± 0.021 kJ/mol 18.99730604 ± 0.00000050 14701-07-6*0 1-Methylethenyl anion [CH3CCH2]- (g) 199.4 188.2 ± 2.0 kJ/mol 41.0723 ± 0.0024 65887-19-6*0 Acrolein CH2CHCHO (g) -55.12 -65.21 ± 0.64 kJ/mol 56.0633 ± 0.0024 107-02-8*0 Fluoroimidogen NF (g, singlet) 369.43 369.41 ± 0.80 kJ/mol 33.005143 ± 0.000070 13967-06-1*2 Nitrous acid anion [HONO]- (g, trans) -105.4 -109.4 ± 1.8 kJ/mol 47.01403 ± 0.00061 256393-36-9*1 Acetylene anion [HCCH]- (g) 356.9 356.7 ± 1.9 kJ/mol 26.0378 ± 0.0016 50443-89-5*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 Peroxyhypochlorous acid anion [HOOCl]- (g, trans quartet) -2.8 -3.3 ± 2.6 kJ/mol 68.4600 ± 0.0011 *67952-08-3*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 Polyoxymethylene CH2O (cr, polyoxymethylene) -170.86 ± 0.21 kJ/mol 30.02598 ± 0.00087 9002-81-7*500 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 1011.3 ± 1.8 kJ/mol 54.0468 ± 0.0024 87612-93-9*0 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 1542.8 ± 2.8 kJ/mol 53.0389 ± 0.0024 *85905-64-2*1 mu-Oxodichlorine cation [ClOCl]+ (g) 1130.45 1126.84 ± 0.63 kJ/mol 86.9043 ± 0.0018 51174-96-0*0 Acetaldehyde CH3CHO (cr,l) -186.91 -191.62 ± 0.28 kJ/mol 44.0526 ± 0.0017 75-07-0*500 (Hydroxyimino)methyl HCNOH (g, trans-cis) 258.9 252.7 ± 2.0 kJ/mol 44.03272 ± 0.00087 206442-92-4*2 Formaldehyde CH2O (aq, unhydrol) -165.65 ± 0.22 kJ/mol 30.02598 ± 0.00087 50-00-0*1000 Water H2O (g, para) -238.904 -241.807 ± 0.022 kJ/mol 18.01528 ± 0.00033 7732-18-5*2 Ammonia NH3 (aq, 5000 H2O) -80.50 ± 0.41 kJ/mol 17.03056 ± 0.00022 7664-41-7*844 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 Hydrogen peroxide cation [HOOH]+ (g, trans, ortho) 897.30 890.31 ± 0.51 kJ/mol 34.01413 ± 0.00062 12325-10-9*11 Ammonia NH3 (aq, 3 H2O) -78.87 ± 0.41 kJ/mol 17.03056 ± 0.00022 7664-41-7*805 Ammonia NH3 (aq, 50 H2O) -80.52 ± 0.41 kJ/mol 17.03056 ± 0.00022 7664-41-7*822 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 Ammonia NH3 (aq, 4 H2O) -79.33 ± 0.41 kJ/mol 17.03056 ± 0.00022 7664-41-7*807 2-(Methylidyneamino)ethenyl CHCHNCH (g, singlet) 600.7 596.4 ± 1.2 kJ/mol 53.0627 ± 0.0024 123416-74-0*1 2-Iminoethyl CH2CHNH (g, syn) 221.7 210.4 ± 1.8 kJ/mol 42.0599 ± 0.0016 73843-90-0*1 Ammonia NH3 (aq, 10000 H2O) -80.44 ± 0.41 kJ/mol 17.03056 ± 0.00022 7664-41-7*850 Methylene CH2 (g) 391.081 391.627 ± 0.094 kJ/mol 14.02658 ± 0.00081 2465-56-7*0 sec-Butylium [CH3CH2CHCH3]+ (g) 792.8 769.2 ± 1.5 kJ/mol 57.1137 ± 0.0033 16548-59-7*0 Ammonia NH3 (aq, 50000 H2O) -80.22 ± 0.41 kJ/mol 17.03056 ± 0.00022 7664-41-7*855 2-Iminoethyl anion [CH2CHNH]- (g, anti) 110.7 100.2 ± 2.3 kJ/mol 42.0604 ± 0.0016 73843-87-5*2 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-Iminoethylium [CH2CHNH]+ (g, singlet) 1108.3 1097.7 ± 2.9 kJ/mol 42.0594 ± 0.0016 73843-91-1*2 Hydroxymethylene HCOH (g) 112.71 108.95 ± 0.27 kJ/mol 30.02598 ± 0.00087 19710-56-6*0 Oxonium [H3O]+ (g, para) 605.89 599.14 ± 0.17 kJ/mol 19.02267 ± 0.00037 13968-08-6*2 (E)-2-Iminoethylium [CH2CHNH]+ (g, anti) 1108.3 1094.9 ± 2.9 kJ/mol 42.0594 ± 0.0016 91127-33-2*0 (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 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) 586.1 579.4 ± 2.2 kJ/mol 52.0746 ± 0.0032 50682-90-1*0 Fluorine atom pentacation [F]+5 (g) 30617.6 30619.4 ± 1.8 kJ/mol 18.99566030 ± 0.00000050 14701-05-4*0 2-Chloro ozone ClO(O)O (g) 265.7 265.1 ± 3.7 kJ/mol 83.4509 ± 0.0013 *141801-66-3*0 Hydrogen fluoride HF (aq, 100 H2O) -322.01 ± 0.10 kJ/mol 20.006343 ± 0.000070 7664-39-3*828 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 Dioxaziridine HN(OO) (g) 277.5 270.8 ± 1.9 kJ/mol 47.01348 ± 0.00061 67394-35-8*0 Oxoniumyl ion [H2O]+ (g, ortho) 978.494 975.591 ± 0.024 kJ/mol 18.01473 ± 0.00033 56583-62-1*1 Trihydrogen (H)(HH) (g, vdW) 215.9 218.3 ± 1.1 kJ/mol 3.02382 ± 0.00021 12184-91-7*100 Silicon atom dication [Si]+2 (g) 2813.98 2816.96 ± 0.56 kJ/mol 28.08440 ± 0.00030 14175-55-4*0 Silicon atom trication [Si]+3 (g) 6045.56 6048.54 ± 0.56 kJ/mol 28.08385 ± 0.00030 14175-56-5*0 Dioxosilane SiO2 (cr, tridymite) -901.5 -906.3 ± 1.4 kJ/mol 60.08430 ± 0.00067 7631-86-9*515 Oxosilyliumyl [SiO]+ (g) 1022.0 1023.1 ± 2.9 kJ/mol 44.08435 ± 0.00042 12359-18-1*0 Chlorine atom Cl (g, 2P3/2) 119.621 121.228 ± 0.0011 kJ/mol 35.45270 ± 0.00090 22537-15-1*1 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 Ammonia NH3 (aq, 5 H2O) -79.63 ± 0.41 kJ/mol 17.03056 ± 0.00022 7664-41-7*809 1-Hydroperoxyethylium [CH3CHOOH]+ (g, singlet) 690.5 675.6 ± 1.5 kJ/mol 61.0594 ± 0.0017 *126898-98-4*2 Difluorodioxidanium [FOOF]+ (g, cis) 1287.2 1283.1 ± 2.3 kJ/mol 69.99506 ± 0.00060 *7783-44-0*2 Nitrogen atom trication [N]+3 (g) 9306.69 9308.55 ± 0.23 kJ/mol 14.005094 ± 0.000070 18396-22-0*0 mu-Hydrotetrahydrodisilicon cation [SiH2(HSiH2)]+ (g) 981.5 968.8 ± 2.8 kJ/mol 61.21015 ± 0.00069 160896-65-1*0 Di-mu-hydrotrihydrodisilicon cation [SiH2(HSiHH)]+ (g) 1033.6 1020.3 ± 2.8 kJ/mol 61.21015 ± 0.00069 *160896-65-1*0 Chlorine atom pentacation [Cl]+5 (g) 19147. 19149. ± 11. kJ/mol 35.44996 ± 0.00090 20337-89-7*0 Disilene anion [SiH2SiH2]- (g) 178.6 170.1 ± 3.0 kJ/mol 60.20331 ± 0.00066 157379-08-3*0 Silylsilylene anion [SiH3SiH]- (g) 160.2 151.6 ± 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 Hydrazoic acid anion [HNNN]- (g, cis) 316.3 310.1 ± 2.3 kJ/mol 43.02871 ± 0.00022 203264-98-6*2 Hydroxylamine NH2OH (g) -33.06 -43.43 ± 0.42 kJ/mol 33.02996 ± 0.00037 7803-49-8*0 2-Hydroperoxyethyl CH2CH2OOH (g, anti-anti) 65.1 51.3 ± 2.2 kJ/mol 61.0599 ± 0.0017 126898-97-3*11 2-Aminoethenylium [CHCHNH2]+ (g, syn triplet) 1118.0 1106.8 ± 2.4 kJ/mol 42.0594 ± 0.0016 64724-21-6*11 mu-Hydrotrihydrodisilicon cation [Si(HSiH3)]+ (g) 1160.1 1152.0 ± 2.6 kJ/mol 60.20221 ± 0.00066 *497967-55-2*0 2-Aminoethenyl anion [CHCHNH2]- (g, syn) 242.0 231.3 ± 2.6 kJ/mol 42.0604 ± 0.0016 *64724-21-6*1 Silyloxoniumylidene [SiH3O]+ (g, triplet) 1096.2 1089.9 ± 2.9 kJ/mol 47.10817 ± 0.00047 152720-17-7*1 Hydroxysilylium [SiH2OH]+ (g) 600.3 591.6 ± 2.9 kJ/mol 47.10817 ± 0.00047 66639-72-3*0 1,5-Hexadiyne HCCCH2CH2CCH (cr,l) 386.0 ± 1.9 kJ/mol 78.1118 ± 0.0048 628-16-0*500 Nitrogen atom tetracation [N]+4 (g) 16781.74 16783.61 ± 0.23 kJ/mol 14.004546 ± 0.000070 14452-70-1*0 Ammonia NH3 (aq, 100 H2O) -80.56 ± 0.41 kJ/mol 17.03056 ± 0.00022 7664-41-7*828 Tetraoxodinitrate anion [O2NNO2]- (g) -184.6 -187.8 ± 2.4 kJ/mol 92.0116 ± 0.0012 63552-02-3*0 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 Deuterium molecule cation [D2]+ (g) 1492.286 1492.361 ± 0.000 kJ/mol 4.02765497609 ± 0.00000000080 12184-84-8*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 Fluorosyl fluoride FFO (g, singlet) 227. 225. ± 21. kJ/mol 53.99621 ± 0.00030 86825-57-2*2 Hypochloroperoxoous acid, hydroxy ester HOOOCl (g, anti) 48.7 41.8 ± 2.5 kJ/mol 84.4588 ± 0.0013 928652-99-7*2 2-Methyl-2-propanol (CH3)3COH (l) -358.9 ± 1.9 kJ/mol 74.1216 ± 0.0033 75-65-0*590 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 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 2-Hydroxyethylium [CH2CH2OH]+ (g, gauche) 1024.8 1012.2 ± 2.0 kJ/mol 45.0600 ± 0.0017 38607-31-7*1 1,2-Diphenylethane C6H5CH2CH2C6H5 (g) 180.70 142.22 ± 0.76 kJ/mol 182.2610 ± 0.0112 103-29-7*0 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) 1192.7 1174.8 ± 3.4 kJ/mol 127.1620 ± 0.0080 79319-68-9*0 Hydrazoic acid HNNN (aq, undissoc) 257.70 ± 0.48 kJ/mol 43.02816 ± 0.00022 7782-79-8*1000 Trioxodinitrate anion [ONN(O)O]- (g, non-vdW) -87.3 -93.0 ± 2.2 kJ/mol 76.01223 ± 0.00091 194856-62-7*1 Formic acid HC(O)OH (aq, undissoc) -425.37 ± 0.45 kJ/mol 46.0254 ± 0.0010 64-18-6*1000 Fluorine atom F (g, 2P3/2) 77.253 79.038 ± 0.017 kJ/mol 18.99840320 ± 0.00000050 14762-94-8*1 Biphenyl C6H5C6H5 (l) 113.7 ± 1.1 kJ/mol 154.2078 ± 0.0096 92-52-4*590 Difluoroaminylium [NF2]+ (g, triplet) 1376.5 1373.9 ± 2.4 kJ/mol 52.002998 ± 0.000070 31685-31-1*1 Benzophenone C6H5C(O)C6H5 (cr) -16.7 -41.9 ± 1.5 kJ/mol 182.2179 ± 0.0104 119-61-9*510 Buckminsterfullerene C60 (g) 2523.9 2519.3 ± 6.4 kJ/mol 720.6420 ± 0.0480 99685-96-8*0 Buckminsterfullerene C60 (cr,l) 2328.8 2338.3 ± 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 Isocyanogen cation [CNCN]+ (g) 1654.2 1656.5 ± 1.4 kJ/mol 52.0343 ± 0.0016 133415-63-1*0 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 Difluorine cation [F2]+ (g) 1514.301 1514.475 ± 0.013 kJ/mol 37.9962578 ± 0.0000010 12184-86-0*0 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 Helium dihydride HeHH (g) -0.05 0.87 ± 0.42 kJ/mol 6.01848 ± 0.00014 33309-42-1*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 Diisocyanogen cation [CNNC]+ (g, cis) 1838.6 1842.6 ± 3.1 kJ/mol 52.0343 ± 0.0016 *78800-21-2*2 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 Fluorine atom trication [F]+3 (g) 11182.872 11186.697 ± 0.032 kJ/mol 18.99675746 ± 0.00000050 14700-88-0*0 Sulfur atom dication [S]+2 (g) 3528.18 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 Dioxathiirane S(OO) (g) 166.2 163.7 ± 2.2 kJ/mol 64.0648 ± 0.0060 191663-73-7*0 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 Chlorine atom hexacation [Cl]+6 (g) 28501. 28503. ± 11. kJ/mol 35.44941 ± 0.00090 22541-73-7*0 Sulfuric acid OS(O)(OH)2 (aq) -878.92 -909.16 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*800 Fluorine atom tetracation [F]+4 (g) 19594.3 19596.6 ± 1.7 kJ/mol 18.99620888 ± 0.00000050 14700-79-9*0 Sulfuric acid OS(O)(OH)2 (aq, 40 H2O) -886.35 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*821 Sulfuric acid OS(O)(OH)2 (aq, 700 H2O) -891.25 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*835 Sulfuric acid OS(O)(OH)2 (aq, 800 H2O) -891.62 ± 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 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) -887.26 ± 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 Iodine monochloride ICl (l) -24.048 ± 0.063 kJ/mol 162.35717 ± 0.00090 7790-99-0*590 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) -900.23 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*849 Sulfuric acid monohydrate (OS(O)(OH)2)(H2O) (cr,l) -1126.33 -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) -1716.09 -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) -2006.94 -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) -2300.37 ± 0.18 kJ/mol 188.1559 ± 0.0066 137168-49-1*500 Sulfuric acid hexahydrate (OS(O)(OH)2)(H2O)6 (cr,l) -2588.92 ± 0.20 kJ/mol 206.1712 ± 0.0068 137168-50-4*500 Sulfuric acid heptahydrate (OS(O)(OH)2)(H2O)7 (cr,l) -2876.87 ± 0.22 kJ/mol 224.1864 ± 0.0069 137168-51-5*500 Sulfuric acid octahydrate (OS(O)(OH)2)(H2O)8 (cr,l) -3164.38 ± 0.24 kJ/mol 242.2017 ± 0.0071 88434-16-6*500 Sulfuric acid nonahydrate (OS(O)(OH)2)(H2O)9 (cr,l) -3451.54 ± 0.26 kJ/mol 260.2170 ± 0.0073 137168-52-6*500 Sulfuric acid decahydrate (OS(O)(OH)2)(H2O)10 (cr,l) -3738.43 ± 0.27 kJ/mol 278.2323 ± 0.0075 137168-53-7*500 Sulfuric acid dodecahydrate (OS(O)(OH)2)(H2O)12 (cr,l) -4311.64 ± 0.31 kJ/mol 314.2628 ± 0.0079 30383-99-4*500 Sulfuric acid pentadecahydrate (OS(O)(OH)2)(H2O)15 (cr,l) -5170.54 ± 0.38 kJ/mol 368.3087 ± 0.0086 425605-43-2*500 Ammonia NH3 (aq, 10 H2O) -80.16 ± 0.41 kJ/mol 17.03056 ± 0.00022 7664-41-7*815 Trioxygen difluoride FOOOF (g) 112.5 107.3 ± 1.1 kJ/mol 85.99501 ± 0.00090 16829-28-0*0 Sulfur tetraoxide OS(O)(O)O (g, triplet Td) -205.1 -211.3 ± 2.6 kJ/mol 96.0636 ± 0.0061 12772-98-4*12 Cyclopentadiene CH2(CHCHCHCH) (l) 110.34 ± 0.56 kJ/mol 66.1011 ± 0.0040 542-92-7*590 Dioxoperoxysulfane (O2S)(OO) (g, singlet Cs ?) -177.1 -177.5 ± 3.5 kJ/mol 96.0636 ± 0.0061 *103613-08-7*12 Thioformaldehyde cation [CH2S]+ (g) 1025.9 1022.3 ± 2.0 kJ/mol 46.0920 ± 0.0061 61356-81-8*0 Peroxyformate [HC(O)OO]- (g, anti) -320.7 -326.5 ± 1.7 kJ/mol 61.0174 ± 0.0012 104960-05-6*2 Dimethylsulfoxide CH3S(O)CH3 (l) -203.58 ± 0.49 kJ/mol 78.1344 ± 0.0062 67-68-5*590 2,3-Dimethylbutane CH3CH(CH3)CH(CH3)CH3 (cr,l) -182.41 -206.92 ± 0.81 kJ/mol 86.1754 ± 0.0049 79-29-8*500 Hydrogen peroxide cation [HOOH]+ (g, cis, para) 931.06 924.20 ± 0.98 kJ/mol 34.01413 ± 0.00062 12325-10-9*22 Cyanoamidogen HNCN (g, c-quartet) 657.4 654.6 ± 2.0 kJ/mol 41.03212 ± 0.00082 12347-01-2*22 Peroxyformyl HC(O)OO (g, anti) -90.4 -95.9 ± 1.7 kJ/mol 61.0168 ± 0.0012 56240-83-6*2 Hydrogen chloride HCl (aq, 25 H2O) -164.169 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*819 Oxirene O(CHCH) (g) 272.42 270.26 ± 0.60 kJ/mol 42.0367 ± 0.0016 157-18-6*0 Hydrogen fluoride HF (aq, 50000 H2O) -328.57 ± 0.16 kJ/mol 20.006343 ± 0.000070 7664-39-3*855 Oxirene O(CHCH) (g, triplet) 387.8 384.4 ± 1.3 kJ/mol 42.0367 ± 0.0016 157-18-6*1 Hydroxyformyl anion [HOCO]- (g) -319.54 -321.40 ± 0.56 kJ/mol 45.0180 ± 0.0010 78944-70-4*0 Hydrogen iodide HI (aq, 30 H2O) -55.51 ± 0.11 kJ/mol 127.912410 ± 0.000076 10034-85-2*820 Ethynol cation [HCCOH]+ (g) 1063.8 1061.2 ± 2.9 kJ/mol 42.0361 ± 0.0016 84005-02-7*0 1-Hydroxyethenylium [CH2COH]+ (g) 841.8 834.9 ± 1.4 kJ/mol 43.0441 ± 0.0016 41084-89-3*0 Diazene anion [HNNH]- (g, trans-cis-iso equilib) 265.6 258.8 ± 2.0 kJ/mol 30.02991 ± 0.00020 100429-75-2*0 Ethynol anion [HCCOH]- (g) 163.5 165.0 ± 3.3 kJ/mol 42.0372 ± 0.0016 864971-50-6*0 Hydrogen bromide HBr (aq, 100 H2O) -119.51 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*828 Hydrogen chloride HCl (aq, 111 H2O) -165.819 ± 0.024 kJ/mol 36.46064 ± 0.00090 7647-01-0*892 Hydrogen chloride HCl (aq, 55.51 H2O) -165.293 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*891 Trihydrogen HHH (g, TS) 254.5 250.7 ± 1.2 kJ/mol 3.02382 ± 0.00021 12184-91-7*200 Iodine monochloride ICl (cr,l) -36.511 -35.537 ± 0.063 kJ/mol 162.35717 ± 0.00090 7790-99-0*500 Cyanomethylium [CH2CN]+ (g) 1256.22 1253.58 ± 0.61 kJ/mol 40.0435 ± 0.0016 34430-18-7*0 Chlorine atom Cl (g, 2P1/2) 130.176 131.783 ± 0.0011 kJ/mol 35.45270 ± 0.00090 22537-15-1*2 Nitrosodioxaziridine ONN(OO) (g) 413.7 408.2 ± 1.8 kJ/mol 76.01168 ± 0.00091 132871-99-9*0 Carbonate [OC(O)O]-2 (aq) -675.163 ± 0.053 kJ/mol 60.0100 ± 0.0012 3812-32-6*800 1-Methoxyethenol CH2C(OH)OCH3 (g) -284.2 -302.7 ± 1.2 kJ/mol 74.0785 ± 0.0025 4453-91-2*0 Hydrogen peroxide cation [HOOH]+ (g, cis, ortho) 931.08 924.20 ± 0.98 kJ/mol 34.01413 ± 0.00062 12325-10-9*21 Hydrogen bromide HBr (aq, 12 H2O) -116.68 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*816 Fluorine atom nonacation [F]+9 (g) 262121.1 262122.9 ± 1.8 kJ/mol 18.99346598 ± 0.00000050 35424-07-8*0 Diazene cation [HNNH]+ (g, trans-cis equilib) 1132.53 1125.60 ± 0.64 kJ/mol 30.02881 ± 0.00020 76986-17-9*1 Ethynol HCCOH (g, t-c triplet) 406.4 403.2 ± 3.2 kJ/mol 42.0367 ± 0.0016 32038-79-2*12 Hydrogen isocyanide anion [HNC]- (g) 191.63 191.81 ± 0.32 kJ/mol 27.02593 ± 0.00081 96913-22-3*0 1-Hydroxyethenylium [CH2COH]+ (g, syn-triplet) 1045.7 1038.7 ± 3.4 kJ/mol 43.0441 ± 0.0016 41084-89-3*12 1-Hydroxyethenyl anion [CH2COH]- (g) 15.1 8.6 ± 2.1 kJ/mol 43.0452 ± 0.0016 112539-13-6*0 Ammonium hydroxide NH4OH (aq, 7000 H2O) -366.28 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*846 Hydrogen peroxide HOOH (aq) -190.70 ± 0.30 kJ/mol 34.01468 ± 0.00062 7722-84-1*800 Hydrogen chloride HCl (aq, 10000 H2O) -166.847 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*850 Ethynol HCCOH (g, t-t triplet) 409.4 406.3 ± 3.2 kJ/mol 42.0367 ± 0.0016 32038-79-2*13 Ethynol HCCOH (g, c-t triplet) 455.5 452.2 ± 3.2 kJ/mol 42.0367 ± 0.0016 32038-79-2*14 1-Hydroxyethenyl anion [CH2COH]- (g, anti) 16.5 9.8 ± 2.7 kJ/mol 43.0452 ± 0.0016 112539-13-6*21 Cyclopentadienide [CH(CHCHCHCH)]- (g) 101.0 88.0 ± 1.0 kJ/mol 65.0937 ± 0.0040 12127-83-2*0 Ethynol HCCOH (g, c-c triplet) 464.2 460.9 ± 3.2 kJ/mol 42.0367 ± 0.0016 32038-79-2*15 Cyanoamidogen anion [HNCN]- (g, triplet) 391.7 389.9 ± 1.8 kJ/mol 41.03267 ± 0.00082 67131-47-9*1 3-Diaziridinylidene C(NHNH) (g) 521.8 515.0 ± 1.5 kJ/mol 42.04006 ± 0.00082 85513-79-7*0 trans-Cycloheptene CH2(CHCHCH2CH2CH2CH2) (g) 142.0 103.9 ± 1.9 kJ/mol 96.1702 ± 0.0057 45509-99-7*0 Perchloric acid cation [HOCl(O)(O)O]+ (g) 1190.2 1180.6 ± 3.3 kJ/mol 100.4577 ± 0.0015 91712-47-9*0 3-Diaziridinylidene C(NHNH) (g, syn) 537.0 530.3 ± 2.0 kJ/mol 42.04006 ± 0.00082 85513-79-7*2 Hydrogen iodide HI (aq, 40 H2O) -55.697 ± 0.096 kJ/mol 127.912410 ± 0.000076 10034-85-2*821 Hydrogen bromide HBr (aq, 50000 H2O) -120.44 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*855 3-Diaziridinylidene cation [C(NHNH)]+ (g) 1479.7 1473.7 ± 2.4 kJ/mol 42.03951 ± 0.00082 *85513-79-7*0 Hydrogen iodide HI (aq, 50 H2O) -55.806 ± 0.096 kJ/mol 127.912410 ± 0.000076 10034-85-2*822 Hypobromous acid cation [HOBr]+ (g) 975.25 964.63 ± 0.54 kJ/mol 96.9108 ± 0.0010 154804-02-1*0 3-Diaziridinylidene cation [C(NHNH)]+ (g, syn) 1497.3 1491.8 ± 3.1 kJ/mol 42.03951 ± 0.00082 *85513-79-7*2 1-Hydroxy-2-propanone CH3C(O)CH2OH (g) -354.45 -373.78 ± 0.84 kJ/mol 74.0785 ± 0.0025 116-09-6*0 Hydrogen chloride HCl (aq, 150 H2O) -165.977 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*829 Diazanide [NH2NH]- (g) 249.3 239.3 ± 3.1 kJ/mol 31.03785 ± 0.00025 25415-88-7*0 Nitrogen atom heptacation [N]+7 (g) 143853.27 143855.13 ± 0.23 kJ/mol 14.002900 ± 0.000070 40549-08-4*0 Hydrogen fluoride HF (aq, 15 H2O) -321.78 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*817 Formic acid HC(O)OH (aq, 2000 H2O) -425.36 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*841 2-Cyclopropyn-1-ylidene C(CC) (g) 898.4 905.3 ± 1.5 kJ/mol 36.0321 ± 0.0024 102508-15-6*0 Oxiranylidene CH2(CO) (g) 213.5 209.3 ± 1.4 kJ/mol 42.0367 ± 0.0016 50983-85-2*0 Indane cation [C6H4(CH2CH2CH2)]+ (g) 909.4 879.5 ± 1.7 kJ/mol 118.1752 ± 0.0072 78854-02-1*0 Hydrogen chloride HCl (aq, 15 H2O) -162.855 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*817 Hydrogen bromide HBr (aq, 111 H2O) -119.56 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*892 Indene cation [C6H4(CHCHCH2)]+ (g) 970.01 946.77 ± 0.75 kJ/mol 116.1593 ± 0.0072 42949-13-3*0 Chlorine atom dianion [Cl]-2 (g) 406.6 408.2 ± 4.8 kJ/mol 35.45380 ± 0.00090 33944-49-9*0 Phenol cation [C6H5OH]+ (g) 746.45 727.66 ± 0.63 kJ/mol 94.1107 ± 0.0048 40932-22-7*0 Phenol anion [C6H5OH]- (g) 23.1 8.1 ± 4.9 kJ/mol 94.1118 ± 0.0048 38752-11-3*0 Hydrogen fluoride HF (aq, 200 H2O) -322.08 ± 0.10 kJ/mol 20.006343 ± 0.000070 7664-39-3*830 Formic acid HC(O)OH (aq, 5000 H2O) -425.37 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*844 Diazene HNNH (g, trans-cis-iso equilib) 207.17 200.03 ± 0.40 kJ/mol 30.02936 ± 0.00020 3618-05-1*0 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 Diazene anion [HNNH]- (g, trans-cis equilib) 265.6 258.8 ± 2.0 kJ/mol 30.02991 ± 0.00020 100429-75-2*1 Hydroperoxonium [H2OOH]+ (g, cis) 762.6 752.7 ± 2.0 kJ/mol 35.02207 ± 0.00064 70850-26-9*2 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 Ammonium hydroxide NH4OH (aq, 750 H2O) -366.38 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*836 Hydrogen fluoride HF (aq, 700 H2O) -322.50 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*835 Ammonium hydroxide NH4OH (aq, 1.5 H2O) -364.33 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*802 Benzoyl anion [C6H5CO]- (g) 70.2 57.6 ± 4.0 kJ/mol 105.1145 ± 0.0056 78944-74-8*0 2-Propene-1,2-diol CH2C(OH)CH2OH (g) -295.4 -314.4 ± 1.2 kJ/mol 74.0785 ± 0.0025 44169-27-9*0 Ammonium hydroxide NH4OH (aq, 2000 H2O) -366.35 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*841 Propynylidene HCCCH (g, singlet) 597.9 599.6 ± 1.2 kJ/mol 38.0480 ± 0.0024 67152-18-5*2 Carbon dianion [C]-2 (g) 1027.5 1033.0 ± 4.9 kJ/mol 12.01180 ± 0.00080 50802-47-6*0 Hydrogen chloride HCl (aq, 200 H2O) -166.102 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*830 Carbonylmethyloxonium [CH3OCO]+ (g) 561.2 553.0 ± 3.0 kJ/mol 59.0435 ± 0.0017 24434-00-2*0 Formic acid HC(O)OH (aq, 10000 H2O) -425.37 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*850 Hydrogen bromide HBr (aq, 150 H2O) -119.67 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*829 Methoxyoxomethyl CH3OCO (g) -152.7 -160.4 ± 1.2 kJ/mol 59.0440 ± 0.0017 16481-04-2*0 Nitric oxide NO (aq, undissoc) 79.219 ± 0.078 kJ/mol 30.00614 ± 0.00031 10102-43-9*1000 Hydrogen fluoride HF (aq, 800 H2O) -322.57 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*837 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, 55.51 H2O) -55.856 ± 0.096 kJ/mol 127.912410 ± 0.000076 10034-85-2*891 Methoxyoxomethyl CH3OCO (g, anti-eclipsed) -151.8 -159.9 ± 2.1 kJ/mol 59.0440 ± 0.0017 16481-04-2*3 Fluorine atom F (g, 2P1/2) 82.088 83.873 ± 0.017 kJ/mol 18.99840320 ± 0.00000050 14762-94-8*2 Hydrogen bromide HBr (aq, 200 H2O) -119.75 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*830 Acetyloxoniumylidene [CH3C(O)O]+ (g, triplet) 892.3 883.9 ± 2.9 kJ/mol 59.0435 ± 0.0017 67057-47-0*1 Trichlorine cation [Cl3]+ (g, triplet) 1196.6 1197.2 ± 3.2 kJ/mol 106.3576 ± 0.0027 33088-85-6*1 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 Hydrogen chloride HCl (aq, 2400 H2O) -166.708 ± 0.024 kJ/mol 36.46064 ± 0.00090 7647-01-0*896 (Iminomethyl)imidogen HNCHN (g) 420.1 413.3 ± 2.9 kJ/mol 42.04006 ± 0.00082 87570-07-8*0 (Iminomethyl)imidogen HNCHN (g, syn-triplet) 430.4 423.5 ± 3.3 kJ/mol 42.04006 ± 0.00082 87570-07-8*12 Hexafluorobenzene cation [C6F6]+ (g) 13.71 9.92 ± 0.87 kJ/mol 186.0541 ± 0.0048 34528-23-9*0 Hydrogen chloride HCl (aq, 2000 H2O) -166.680 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*841 Hydrogen bromide HBr (aq, 300 H2O) -119.86 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*831 Propargylenide [HCCCH]- (g) 434.5 437.7 ± 1.1 kJ/mol 38.0485 ± 0.0024 82906-05-6*0 2-Propenylidene CHCHCH2 (g, triplet) 417.6 410.6 ± 1.5 kJ/mol 40.0639 ± 0.0024 19527-08-3*1 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 Hydrazine anion [NH2NH2]- (g) 232.3 218.0 ± 4.1 kJ/mol 32.04579 ± 0.00031 65391-88-0*0 Acetate [CH3C(O)O]- (aq) -485.10 ± 0.27 kJ/mol 59.0446 ± 0.0017 71-50-1*800 Acetic acid CH3C(O)OH (aq, undissoc) -484.79 ± 0.27 kJ/mol 60.0520 ± 0.0017 64-19-7*1000 O--HH Complex (H2)(O) (g, vdW Cinfv ?) 247.7 249.0 ± 2.7 kJ/mol 18.01528 ± 0.00033 *7732-18-5*101 Cyclopropane CH2(CH2CH2) (l) 41.50 35.82 ± 0.47 kJ/mol 42.0797 ± 0.0024 75-19-4*500 (Formyloxy)methyl HC(O)OCH2 (g) -151.3 -159.4 ± 1.1 kJ/mol 59.0440 ± 0.0017 3122-12-1*0 Water H2O (cr, eq.press.) -286.276 -292.717 ± 0.022 kJ/mol 18.01528 ± 0.00033 7732-18-5*509 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, 0.5 H2O) -483.01 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*923 2-(Cyclopenta-2,4-dien-1-ylidene)ethan-1-ide [CH2CHC(CHCHCHCH)]- (g) 132.4 114.3 ± 3.4 kJ/mol 91.1310 ± 0.0056 405519-46-2*0 Tetrafluorohydrazine cation [NF2NF2]+ (g) 1129.2 1123.0 ± 2.5 kJ/mol 104.00654 ± 0.00014 37366-75-9*0 Hydrogen iodide HI (aq, 75 H2O) -55.965 ± 0.099 kJ/mol 127.912410 ± 0.000076 10034-85-2*825 Carboxymethyl CH2C(O)OH (g) -226.6 -236.4 ± 1.1 kJ/mol 59.0440 ± 0.0017 2887-46-9*0 1,3-Butadiyne-1,4-diyl CCCC (g, singlet) 1084.01 1093.82 ± 0.83 kJ/mol 48.0428 ± 0.0032 78015-07-3*2 Tetraoxidanyl HOOOO (g) 2.1 0.4 ± 2.9 kJ/mol 65.0055 ± 0.0012 69696-93-1*0 Diazenide [NNH]- (g) 175.7 176.7 ± 1.6 kJ/mol 29.02197 ± 0.00016 71004-29-0*0 Hydrogen fluoride HF (aq, 500000 H2O) -333.04 ± 0.16 kJ/mol 20.006343 ± 0.000070 7664-39-3*866 2-Methoxy-2-oxoethyl CH2C(O)OCH3 (g) -202.9 -218.1 ± 1.5 kJ/mol 73.0706 ± 0.0025 54668-31-4*0 Nitric acid HON(O)O (aq, 500 H2O) -206.16 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*833 Pyridiniumyl [N(CHCHCHCHCH)]+ (g) 1051.32 1035.38 ± 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 Carbon trianion [C]-3 (g) 1813.2 1818.6 ± 5.9 kJ/mol 12.01235 ± 0.00080 50802-48-7*0 Acetic acid CH3C(O)OH (aq, 1 H2O) -482.91 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*801 Hydrogen fluoride HF (aq, 18.5 H2O) -321.82 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*887 Propylidene CH3CH2CH (g) 349.51 335.82 ± 0.92 kJ/mol 42.0797 ± 0.0024 6700-78-3*0 Acetone enol CH3C(OH)CH2 (g) -151.22 -168.03 ± 0.75 kJ/mol 58.0791 ± 0.0025 29456-04-0*0 Acetone enol CH3C(OH)CH2 (g, anti) -145.1 -162.5 ± 1.9 kJ/mol 58.0791 ± 0.0025 29456-04-0*2 Hydrogen bromide HBr (aq, 400 H2O) -119.93 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*832 Oxoethylidene HCC(O)H (g) 261.1 258.3 ± 1.1 kJ/mol 42.0367 ± 0.0016 39920-84-8*0 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 iodide HI (aq, 100 H2O) -56.044 ± 0.097 kJ/mol 127.912410 ± 0.000076 10034-85-2*828 Oxoethylidene anion [HCC(O)H]- (g) 86.9 84.2 ± 2.1 kJ/mol 42.0372 ± 0.0016 106543-38-8*0 Ammonium hydroxide NH4OH (aq, 3.5 H2O) -365.30 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*806 Ammonium hydroxide NH4OH (aq, 3000 H2O) -366.34 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*842 1,2,4-Trioxolane O(CH2OOCH2) (g) -209.6 -227.8 ± 3.1 kJ/mol 76.0514 ± 0.0019 289-14-5*0 (Acetyloxy)methyl CH3C(O)OCH2 (g) -200.2 -213.9 ± 1.5 kJ/mol 73.0706 ± 0.0025 2887-49-2*0 Hydrogen fluoride HF (aq, 500 H2O) -322.35 ± 0.10 kJ/mol 20.006343 ± 0.000070 7664-39-3*833 Hydrogen fluoride HF (aq, 1000 H2O) -322.71 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*839 Methyl nitrite CH3ONO (g, trans) -52.30 -64.26 ± 0.89 kJ/mol 61.0401 ± 0.0010 624-91-9*1 Methyl nitrite CH3ONO (cr,l) -88.65 ± 0.54 kJ/mol 61.0401 ± 0.0010 624-91-9*500 2-Propenylidene CHCHCH2 (g) 417.6 410.6 ± 1.5 kJ/mol 40.0639 ± 0.0024 19527-08-3*0 Difluorodiazene FNNF (g) 78.5 73.4 ± 2.1 kJ/mol 66.01029 ± 0.00014 10578-16-2*0 Ethyl nitrite CH3CH2ONO (g, gauche-trans) -80.1 -98.3 ± 1.9 kJ/mol 75.0666 ± 0.0017 109-95-5*2 Ethyl nitrite CH3CH2ONO (g, gauche-cis) -78.0 -96.9 ± 1.9 kJ/mol 75.0666 ± 0.0017 109-95-5*3 Hydrogen bromide HBr (aq, 500 H2O) -119.97 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*833 Propyl nitrite CH3CH2CH2ONO (g) -95.7 -119.6 ± 1.8 kJ/mol 89.0932 ± 0.0025 543-67-9*0 Propyl nitrite CH3CH2CH2ONO (g, trans-trans-cis) -95.4 -120.1 ± 2.5 kJ/mol 89.0932 ± 0.0025 543-67-9*2 Propyl nitrite CH3CH2CH2ONO (g, gauche-gauche-trans) -95.6 -120.1 ± 2.5 kJ/mol 89.0932 ± 0.0025 543-67-9*3 Propyl nitrite CH3CH2CH2ONO (g, gauche-gauche-trans II) -94.8 -119.4 ± 2.5 kJ/mol 89.0932 ± 0.0025 543-67-9*4 Propyl nitrite CH3CH2CH2ONO (g, trans-gauche-trans) -94.7 -119.0 ± 2.5 kJ/mol 89.0932 ± 0.0025 543-67-9*5 Propyl nitrite CH3CH2CH2ONO (g, trans-gauche-cis) -92.8 -117.8 ± 2.5 kJ/mol 89.0932 ± 0.0025 543-67-9*6 Propyl nitrite CH3CH2CH2ONO (g, gauche-gauche-cis) -92.6 -117.7 ± 2.5 kJ/mol 89.0932 ± 0.0025 543-67-9*7 Propyl nitrite CH3CH2CH2ONO (g, gauche-gauche-cis II) -91.2 -116.1 ± 2.8 kJ/mol 89.0932 ± 0.0025 543-67-9*8 1,2-Dibromoethene CHBrCHBr (g) 121.3 101.2 ± 2.0 kJ/mol 185.8453 ± 0.0026 540-49-8*0 Tetroxidane HOOOOH (g) -33.33 -43.26 ± 0.44 kJ/mol 66.0135 ± 0.0012 29683-94-1*0 2-Hydroxyethenyl CHCHOH (g) 137.99 132.17 ± 0.72 kJ/mol 43.0446 ± 0.0016 108665-16-3*0 Ethynylamidogen anion [HCCNH]- (g) 233.7 230.5 ± 3.2 kJ/mol 40.0446 ± 0.0016 64066-03-1*0 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, 111 H2O) -56.073 ± 0.096 kJ/mol 127.912410 ± 0.000076 10034-85-2*892 Dioxymethylene HCOO (g) 341.8 339.8 ± 3.0 kJ/mol 45.0174 ± 0.0010 438586-67-5*0 Dichloromethylene CCl2 (g) 229.87 231.05 ± 0.64 kJ/mol 82.9161 ± 0.0020 1605-72-7*0 Hydrogen iodide HI (aq, 8 H2O) -52.22 ± 0.12 kJ/mol 127.912410 ± 0.000076 10034-85-2*813 Hydrogen chloride HCl (aq, 30 H2O) -164.500 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*820 Acetic acid CH3C(O)OH (aq, 1.5 H2O) -482.85 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*802 Acetic acid CH3C(O)OH (aq, 2 H2O) -482.87 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*803 Acetic acid CH3C(O)OH (aq, 2.5 H2O) -482.96 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*804 Diazene HNNH (g, trans-cis equilib) 207.17 200.03 ± 0.40 kJ/mol 30.02936 ± 0.00020 3618-05-1*1 Ethynylaminylium [HCCNH]+ (g) 1277.8 1277.4 ± 2.6 kJ/mol 40.0435 ± 0.0016 103835-08-1*0 Ozone OOO (aq, undissoc) 118.20 ± 0.75 kJ/mol 47.99820 ± 0.00090 10028-15-6*1000 2-Propenylidene CHCHCH2 (g, triplet syn) 419.2 411.6 ± 2.3 kJ/mol 40.0639 ± 0.0024 19527-08-3*12 Ammonium hydroxide NH4OH (aq, 900 H2O) -366.38 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*838 1,1-Dibromoethane CH3CHBr2 (cr,l) -67.0 ± 1.3 kJ/mol 187.8612 ± 0.0026 557-91-5*500 Oxide [O]-2 (g) 651. 653. ± 15. kJ/mol 16.00050 ± 0.00030 16833-27-5*0 Hydrogen bromide HBr (aq, 15 H2O) -117.38 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*817 Ammonium hydroxide NH4OH (aq, 4.5 H2O) -365.54 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*808 Dioxoethylium [OCHCO]+ (g) 688.6 689.9 ± 2.9 kJ/mol 57.0276 ± 0.0017 *1994332-01-2*0 3-Buten-2-one CH3C(O)CHCH2 (g) -95.32 -110.85 ± 0.85 kJ/mol 70.0898 ± 0.0032 78-94-4*0 Acetic acid CH3C(O)OH (aq, 3 H2O) -483.04 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*805 3-Buten-2-one CH3C(O)CHCH2 (g, cis) -93.7 -109.8 ± 1.6 kJ/mol 70.0898 ± 0.0032 78-94-4*2 Methane anion [CH4]- (g) 27.3 19.4 ± 5.1 kJ/mol 16.04301 ± 0.00085 27680-53-1*0 1,3-Butadien-2-ol CH2C(OH)CHCH2 (g, s-trans, anti) -48.0 -64.2 ± 2.3 kJ/mol 70.0898 ± 0.0032 59120-04-6*12 Cyanic fluoride cation [FCN]+ (g) 1294.2 1294.6 ± 1.1 kJ/mol 45.01529 ± 0.00080 62532-69-8*0 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 Acetic acid CH3C(O)OH (aq, 4 H2O) -483.14 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*807 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 Formaldehyde CH2O (g, ortho singlet) -105.255 -109.221 ± 0.095 kJ/mol 30.02598 ± 0.00087 50-00-0*22 Formylimidogen HC(O)N (g, triplet) 245.2 242.1 ± 4.6 kJ/mol 43.02478 ± 0.00086 42288-92-6*1 Hydrogen fluoride HF (aq, 600 H2O) -322.43 ± 0.10 kJ/mol 20.006343 ± 0.000070 7664-39-3*834 Cyanic fluoride anion [FCN]- (g) -20.7 -18.7 ± 2.9 kJ/mol 45.01639 ± 0.00080 34507-50-1*0 Ethanedial anion [OCHCO]- (g) -188.8 -190.3 ± 3.1 kJ/mol 57.0287 ± 0.0017 1994332-01-2*0 Hydrogen fluoride HF (aq, 900 H2O) -322.64 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*838 Iminomethyl HCNH (g) 275.81 272.21 ± 0.56 kJ/mol 28.03332 ± 0.00082 15691-95-9*0 Fluorosyl fluoride FFO (g) 192.8 193.3 ± 2.3 kJ/mol 53.99621 ± 0.00030 86825-57-2*0 Acrolein cation [CH2CHCHO]+ (g) 920.01 910.05 ± 0.79 kJ/mol 56.0627 ± 0.0024 84005-05-0*0 Acrolein cation [CH2CHCHO]+ (g, cis) 930.8 921.0 ± 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) -68.0 -78.0 ± 3.5 kJ/mol 56.0638 ± 0.0024 23555-87-5*1 Hydroxyoxoethenylium [HOCCO]+ (g) 866.4 865.2 ± 3.5 kJ/mol 57.0276 ± 0.0017 *1994332-00-1*0 Hydrogen peroxide cation [HOOH]+ (g, trans, para) 897.32 890.31 ± 0.51 kJ/mol 34.01413 ± 0.00062 12325-10-9*12 Chloromethylene CHCl (g) 320.36 320.65 ± 0.89 kJ/mol 48.4713 ± 0.0012 2108-20-5*0 Hydrogen iodide HI (aq, 9 H2O) -52.89 ± 0.16 kJ/mol 127.912410 ± 0.000076 10034-85-2*814 Propyn-1-ol cation [CH3CCOH]+ (g) 959.9 951.7 ± 3.0 kJ/mol 56.0627 ± 0.0024 84005-04-9*0 Propylidene CH3CH2CH (g, triplet anti) 349.7 336.0 ± 2.0 kJ/mol 42.0797 ± 0.0024 6700-78-3*12 2-Methyloxirene CH3C(CHO) (g, triplet) 344.0 334.8 ± 1.8 kJ/mol 56.0633 ± 0.0024 2835-41-8*1 2-Methyloxirene CH3C(CHO) (g, c-triplet) 346.7 336.8 ± 2.5 kJ/mol 56.0633 ± 0.0024 2835-41-8*12 Ammonium hydroxide NH4OH (aq, 5 H2O) -365.63 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*809 Ethynediolide [HOCCO]- (g) -132.9 -134.0 ± 3.5 kJ/mol 57.0287 ± 0.0017 1994332-00-1*0 Isocyanoamidogen HNNC (g) 489.7 487.7 ± 1.2 kJ/mol 41.03212 ± 0.00082 947408-73-3*0 Ammonium hydroxide NH4OH (aq, 6 H2O) -365.76 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*811 Acetic acid CH3C(O)OH (aq, 4.5 H2O) -483.18 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*808 Acryloyl CH2CHCO (g) 101.2 96.3 ± 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?) 109.5 103.9 ± 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 Hydrogen bromide HBr (aq, 555.1 H2O) -119.99 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*895 Dihydroxymethyl CH(OH)2 (g) -196.9 -205.2 ± 1.1 kJ/mol 47.0333 ± 0.0010 14840-85-8*0 Hydrogen bromide HBr (aq, 20 H2O) -118.02 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*818 1-Formylethenylium [CH2CCHO]+ (g) 1023.5 1018.0 ± 2.3 kJ/mol 55.0548 ± 0.0024 101705-89-9*0 Acetic acid CH3C(O)OH (aq, 5 H2O) -483.22 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*809 Chlorohydroxymethyl CH(Cl)OH (g) -54.7 -60.4 ± 1.1 kJ/mol 65.4787 ± 0.0012 147139-06-8*0 Dihydroxymethyl CH(OH)2 (g, syn-syn) -190.6 -199.3 ± 2.2 kJ/mol 47.0333 ± 0.0010 14840-85-8*2 Nitrosyl nitrite anion [ONONO]- (g) -103.0 -106.2 ± 2.8 kJ/mol 76.01223 ± 0.00091 *122413-35-8*0 3-Oxo-1-propenyl CHCHCHO (g) 190.97 185.43 ± 0.91 kJ/mol 55.0553 ± 0.0024 206255-29-0*0 Hydrogen iodide HI (aq, 10 H2O) -53.38 ± 0.17 kJ/mol 127.912410 ± 0.000076 10034-85-2*815 3-Oxo-1-propenyl CHCHCHO (g, cis) 191.7 185.9 ± 2.1 kJ/mol 55.0553 ± 0.0024 206255-29-0*2 1,3-Propanediyl CH2CH2CH2 (g, triplet) 319.3 307.9 ± 1.3 kJ/mol 42.0797 ± 0.0024 32458-33-6*1 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 Chloroethane CH3CH2Cl (cr,l) -134.34 -135.96 ± 0.25 kJ/mol 64.5138 ± 0.0019 75-00-3*500 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 2-Hydroxyethyl CH2CH2OH (g) -12.89 -26.15 ± 0.48 kJ/mol 45.0605 ± 0.0017 4422-54-2*0 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 21.3 ± 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 Acetic acid CH3C(O)OH (aq, 6 H2O) -483.28 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*811 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 58.4 ± 3.1 kJ/mol 55.0559 ± 0.0024 135924-69-5*12 Isocyanic fluoride cation [FNC]+ (g) 1618.0 1618.6 ± 4.0 kJ/mol 45.01529 ± 0.00080 *16992-26-0*0 1,2-Propadien-1-one anion [CH2CCO]- (g) 49.8 48.5 ± 3.1 kJ/mol 54.0479 ± 0.0024 159171-62-7*0 Peroxyhypochlorous acid cation [HOOCl]+ (g) 1030.4 1024.6 ± 2.5 kJ/mol 68.4589 ± 0.0011 *67952-07-2*0 Isocyanoamidogen HNNC (g, quartet) 828.2 825.6 ± 1.3 kJ/mol 41.03212 ± 0.00082 947408-73-3*2 Dihydroxymethyl CH(OH)2 (g, anti-anti) -187.8 -196.7 ± 2.0 kJ/mol 47.0333 ± 0.0010 14840-85-8*3 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) 179.4 182.0 ± 3.2 kJ/mol 53.0400 ± 0.0024 557113-97-0*0 Tetroxidane HOOOOH (g, C2 I) -31.30 -41.81 ± 0.64 kJ/mol 66.0135 ± 0.0012 29683-94-1*22 Isocyanic fluoride anion [FNC]- (g) 73.9 75.6 ± 5.7 kJ/mol 45.01639 ± 0.00080 357426-78-9*0 Acetic acid CH3C(O)OH (aq, 7 H2O) -483.36 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*812 Formylethynyl anion [CCCHO]- (g) 100.5 101.8 ± 3.4 kJ/mol 53.0400 ± 0.0024 85905-64-2*0 Isocyanoamidogen HNNC (g, t-quartet) 837.9 835.2 ± 2.1 kJ/mol 41.03212 ± 0.00082 947408-73-3*21 2-Cyclopropen-1-one cation [OC(CHCH)]+ (g) 1078.8 1075.7 ± 2.0 kJ/mol 54.0468 ± 0.0024 100815-68-7*0 Hydrogen chloride HCl (aq, 40 H2O) -164.926 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*821 Hydrogen chloride HCl (aq, 4000 H2O) -166.763 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*843 Imidogen NH (g, singlet) 509.34 509.39 ± 0.17 kJ/mol 15.014680 ± 0.000099 13774-92-0*2 Chlorine trifluoride anion [FCl(F)F]- (g) -480.4 -481.9 ± 3.5 kJ/mol 92.44846 ± 0.00090 184289-50-7*0 (Methylamino)methyl anion [CH3NHCH2]- (g) 202.1 185.2 ± 3.1 kJ/mol 44.0763 ± 0.0017 *31277-25-5*0 Isourea NHC(OH)NH2 (g) -156.1 -172.7 ± 2.6 kJ/mol 60.05534 ± 0.00091 4744-36-9*0 Hydrogen chloride HCl (aq, 300 H2O) -166.253 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*831 Hydrogen iodide HI (aq, 150 H2O) -56.136 ± 0.097 kJ/mol 127.912410 ± 0.000076 10034-85-2*829 Carbamoyl anion [NH2CO]- (g) -81.9 -87.8 ± 3.1 kJ/mol 44.03327 ± 0.00087 78944-69-1*0 Tetrafluorohydrazine cation [NF2NF2]+ (g, cis ?) 1146.9 1141.5 ± 3.7 kJ/mol 104.00654 ± 0.00014 37366-75-9*2 Carbamoyl HNCOH (g) 74.1 68.3 ± 2.7 kJ/mol 44.03272 ± 0.00087 *2858-51-7*0 Carbamoyl HNCOH (g, trans-cis) 76.4 69.9 ± 3.2 kJ/mol 44.03272 ± 0.00087 *2858-51-7*2 Carbamoyl HNCOH (g, cis-trans) 96.3 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 Hydrogen bromide HBr (aq, 20000 H2O) -120.40 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*852 Hydrogen chloride HCl (aq, 400 H2O) -166.336 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*832 (Hydroxyimino)methyl HCNOH (g) 250.1 244.4 ± 1.8 kJ/mol 44.03272 ± 0.00087 206442-92-4*0 Oxooxoniumylmethoxy [OC(O)O]+ (g) 1178.0 1177.3 ± 5.7 kJ/mol 60.0084 ± 0.0012 952586-28-6*0 Acetic acid CH3C(O)OH (aq, 8 H2O) -483.44 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*813 (Hydroxyimino)methyl HCNOH (g, cis-trans) 262.6 257.1 ± 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 Cyanogen chloride cation [ClCN]+ (g) 1326.22 1327.55 ± 0.95 kJ/mol 61.4696 ± 0.0012 37612-72-9*0 Propylidyne CH3CH2C (g) 492.7 483.0 ± 1.2 kJ/mol 41.0718 ± 0.0024 85056-54-8*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 Hydrogen bromide HBr (aq, 1 H2O) -71.67 ± 0.13 kJ/mol 80.9119 ± 0.0010 10035-10-6*801 Ammonium hydroxide NH4OH (aq, 8 H2O) -365.92 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*813 Formic acid HC(O)OH (aq, 20000 H2O) -425.38 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*852 Formaldoxime CH2NOH (g) 30.6 20.0 ± 1.3 kJ/mol 45.04066 ± 0.00088 75-17-2*0 Acetic acid CH3C(O)OH (aq, 9 H2O) -483.52 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*814 Ammonium hydroxide NH4OH (aq, 1500 H2O) -366.37 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*840 Methylaminyliumyl [CH3N]+ (g, quartet) 1423.0 1416.0 ± 2.2 kJ/mol 29.04071 ± 0.00083 56924-51-7*2 Hydrogen chloride HCl (aq, 500 H2O) -166.403 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*833 2-Methyliumylidynehydrazin-2-ium-1-ide [HNNC]+ (g) 1544.1 1542.5 ± 1.7 kJ/mol 41.03157 ± 0.00082 *947408-73-3*0 Dihydroxymethylium [CH(OH)2]+ (g) 421.5 410.4 ± 3.0 kJ/mol 47.0328 ± 0.0010 180071-68-5*0 Nitrous acid anion [HONO]- (g) -105.84 -109.31 ± 0.78 kJ/mol 47.01403 ± 0.00061 256393-36-9*0 Dihydroxymethylium [CH(OH)2]+ (g, anti-anti) 428.5 417.3 ± 3.4 kJ/mol 47.0328 ± 0.0010 180071-68-5*3 Cyanogen chloride anion [ClCN]- (g) 46.8 51.2 ± 3.1 kJ/mol 61.4707 ± 0.0012 12281-43-5*0 Hydrogen iodide HI (aq, 100000 H2O) -56.781 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*861 Hydrogen fluoride HF (aq, 22.2 H2O) -321.85 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*888 Ethanimine CH3CHNH (g) 55.81 41.17 ± 0.72 kJ/mol 43.0678 ± 0.0016 20729-41-3*0 Acetic acid CH3C(O)OH (aq, 10 H2O) -483.60 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*815 Hydrogen iodide HI (aq, 200 H2O) -56.195 ± 0.097 kJ/mol 127.912410 ± 0.000076 10034-85-2*830 Hydrogen fluoride HF (aq, 2000 H2O) -323.39 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*841 Ethylideneammoniumylidene [CH3CHN]+ (g, triplet) 1310.0 1300.4 ± 3.0 kJ/mol 42.0594 ± 0.0016 91127-36-5*1 Hydrodioxonitrogen cation [HN(O)O]+ (g) 1130.0 1123.4 ± 2.9 kJ/mol 47.01293 ± 0.00061 252986-76-8*0 Dihydroxymethylium [CH(OH)2]+ (g, syn-syn) 439.4 428.2 ± 3.4 kJ/mol 47.0328 ± 0.0010 180071-68-5*2 1-Cyanoethylidene CH3CCN (g) 437.6 433.8 ± 1.4 kJ/mol 53.0627 ± 0.0024 498544-34-6*0 Hydrogen iodide HI (aq, 300 H2O) -56.274 ± 0.092 kJ/mol 127.912410 ± 0.000076 10034-85-2*831 Ammonium hydroxide NH4OH (aq, 20000 H2O) -366.18 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*852 Ethylideneazanide [CH3CHN]- (g) 147.8 137.6 ± 3.2 kJ/mol 42.0604 ± 0.0016 144810-43-5*0 Acetic acid CH3C(O)OH (aq, 12 H2O) -483.75 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*816 Dihydroxymethanide [CH(OH)2]- (g) -194.2 -202.4 ± 1.8 kJ/mol 47.0339 ± 0.0010 61192-32-3*0 2-Methanidylidynehydrazin-2-ium-1-ide [HNNC]- (g) 281.9 279.1 ± 1.4 kJ/mol 41.03267 ± 0.00082 *947408-74-4*0 Dihydroxymethanide [CH(OH)2]- (g, syn-anti) -192.0 -201.3 ± 2.4 kJ/mol 47.0339 ± 0.0010 61192-32-3*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 Water H2O (cr, l, eq.press.) -286.276 -285.804 ± 0.022 kJ/mol 18.01528 ± 0.00033 7732-18-5*499 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 Propane CH3CH2CH3 (cr,l) -110.18 -121.16 ± 0.66 kJ/mol 44.0956 ± 0.0025 74-98-6*500 Dihydroxymethanide [CH(OH)2]- (g, anti-anti) -177.6 -187.4 ± 2.4 kJ/mol 47.0339 ± 0.0010 61192-32-3*3 Acetic acid CH3C(O)OH (aq, 15 H2O) -483.92 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*817 Methoxyethene CH2CHOCH3 (g) -89.3 -106.6 ± 1.1 kJ/mol 58.0791 ± 0.0025 107-25-5*0 2-(Methylidyneamino)ethenyl CHCHNCH (g) 600.7 596.4 ± 1.2 kJ/mol 53.0627 ± 0.0024 123416-74-0*0 Pentachloroethylium [CCl3CCl2]+ (g) 838.0 836.4 ± 3.3 kJ/mol 201.2844 ± 0.0048 *7094-17-9*0 2-(Methylidyneamino)ethenyl CHCHNCH (g, triplet) 634.5 630.5 ± 1.6 kJ/mol 53.0627 ± 0.0024 123416-74-0*2 Hydrogen iodide HI (aq, 2500 H2O) -56.580 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*898 Hydrogen fluoride HF (aq, 45 H2O) -321.94 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*906 Carbon C (diamond) 2.389 1.861 ± 0.043 kJ/mol 12.01070 ± 0.00080 7440-44-0*501 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 Pentachloroethanide [CCl3CCl2]- (g) -281.8 -280.4 ± 3.9 kJ/mol 201.2854 ± 0.0048 263019-83-6*0 Acetic acid CH3C(O)OH (aq, 20 H2O) -484.10 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*818 2-Methanidylidynehydrazin-2-ium-1-ide [HNNC]- (g, triplet) 518.6 516.2 ± 1.6 kJ/mol 41.03267 ± 0.00082 *947408-74-4*1 Hydrogen iodide HI (aq, 400 H2O) -56.320 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*832 Hydroxymethoxy CH2(OH)O (g, anti) -149.9 -159.8 ± 1.8 kJ/mol 47.0333 ± 0.0010 72144-78-6*1 Dinitrogen anion [N2]- (g) 192.5 192.5 ± 1.7 kJ/mol 28.01403 ± 0.00014 12185-02-3*0 Oxiranylium [CH2(CHO)]+ (g) 901.3 893.3 ± 1.4 kJ/mol 43.0441 ± 0.0016 57789-76-1*0 Acetic acid CH3C(O)OH (aq, 25 H2O) -484.22 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*819 Acetic acid CH3C(O)OH (aq, 30 H2O) -484.31 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*820 2-Cyanovinyl CHCHCN (g) 447.87 445.47 ± 0.98 kJ/mol 52.0547 ± 0.0024 189141-20-6*0 2-Cyanovinylium [CHCHCN]+ (g, triplet) 1517.3 1515.3 ± 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 Water dimer cation [(H2O)2]+ (g) 556.9 546.4 ± 3.0 kJ/mol 36.03001 ± 0.00066 158061-35-9*0 2-Iminoethyl CH2CHNH (g) 219.36 208.68 ± 0.86 kJ/mol 42.0599 ± 0.0016 73843-90-0*0 2-Isocyanovinyl CHCHNC (g) 543.3 541.9 ± 1.7 kJ/mol 52.0547 ± 0.0024 225798-14-1*0 Peroxyhypochlorous acid anion [HOOCl]- (g, quartet) -32.2 -33.9 ± 2.6 kJ/mol 68.4600 ± 0.0011 *67952-08-3*0 Hydroxymethoxy cation [CH2(OH)O]+ (g, triplet) 925.0 915.2 ± 3.2 kJ/mol 47.0328 ± 0.0010 180071-69-6*1 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 Hydrodioxonitrate [HN(O)O]- (g) -62.0 -68.4 ± 3.1 kJ/mol 47.01403 ± 0.00061 61508-71-2*0 Fluoroimidogen NF (g) 232.64 232.64 ± 0.80 kJ/mol 33.005143 ± 0.000070 13967-06-1*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) 583.1 585.4 ± 1.6 kJ/mol 39.0361 ± 0.0016 78694-65-2*0 Nitrogen atom N (g, doublet) 700.558 702.461 ± 0.022 kJ/mol 14.006740 ± 0.000070 17778-88-0*2 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 Oxiranyl anion [CH2(CHO)]- (g) 121.3 113.4 ± 1.5 kJ/mol 43.0452 ± 0.0016 72722-59-9*0 2-Iminoethylium [CH2CHNH]+ (g) 1108.3 1097.7 ± 2.9 kJ/mol 42.0594 ± 0.0016 73843-91-1*0 Hydroxymethoxy cation [CH2(OH)O]+ (g, triplet syn) 930.9 921.4 ± 3.7 kJ/mol 47.0328 ± 0.0010 180071-69-6*12 Acetic acid CH3C(O)OH (aq, 40 H2O) -484.43 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*821 1,2-Dichloroethene CHClCHCl (g) 3.80 -1.52 ± 0.55 kJ/mol 96.9427 ± 0.0024 540-59-0*0 Hydrogen bromide HBr (aq, 25 H2O) -118.36 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*819 Acetic acid CH3C(O)OH (aq, 50 H2O) -484.50 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*822 2-Iminoethylium [CH2CHNH]+ (g, triplet) 1148.7 1140.2 ± 3.3 kJ/mol 42.0594 ± 0.0016 73843-91-1*1 Hydroxymethoxy cation [CH2(OH)O]+ (g, triplet anti) 933.5 923.8 ± 3.7 kJ/mol 47.0328 ± 0.0010 180071-69-6*11 Hydroxymethoxy anion [CH2(OH)O]- (g) -373.82 -383.76 ± 0.85 kJ/mol 47.0339 ± 0.0010 67899-36-9*0 Hydrogen chloride HCl (aq, 555.1 H2O) -166.430 ± 0.024 kJ/mol 36.46064 ± 0.00090 7647-01-0*895 1,3-Cyclobutadiene cation [CH(CHCHCH)]+ (g) 1215.6 1207.2 ± 3.0 kJ/mol 52.0740 ± 0.0032 34531-09-4*0 Hydroxymethoxy anion [CH2(OH)O]- (g, anti) -349.1 -358.7 ± 1.9 kJ/mol 47.0339 ± 0.0010 67899-36-9*1 Acetic acid CH3C(O)OH (aq, 55.51 H2O) -484.54 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*891 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 Trihydrogen H(HH) (g, Ry) 745.878 743.199 ± 0.062 kJ/mol 3.02382 ± 0.00021 12184-91-7*0 Hydroxymethylene cation [HCOH]+ (g) 971.9 968.3 ± 1.4 kJ/mol 30.02543 ± 0.00087 135395-06-1*0 Oxonium [H3O]+ (aq) -285.802 ± 0.022 kJ/mol 19.02267 ± 0.00037 13968-08-6*800 2-Methanidylidynehydrazin-2-ium-1-ide [HNNC]- (g, t-triplet) 531.6 530.3 ± 2.3 kJ/mol 41.03267 ± 0.00082 *947408-74-4*11 Hydrogen fluoride HF (aq, 4000 H2O) -324.13 ± 0.13 kJ/mol 20.006343 ± 0.000070 7664-39-3*843 Dichlorovinylidene CCCl2 (g) 424.2 427.5 ± 3.0 kJ/mol 94.9268 ± 0.0024 20394-25-6*0 Vinylvinylidene CH2CHCHC (g) 494.2 488.9 ± 1.7 kJ/mol 52.0746 ± 0.0032 148759-16-4*0 Vinylvinylidene CH2CHCHC (g, triplet) 690.5 684.7 ± 2.7 kJ/mol 52.0746 ± 0.0032 148759-16-4*1 2-Iminoethyl anion [CH2CHNH]- (g) 104.5 94.1 ± 2.1 kJ/mol 42.0604 ± 0.0016 73843-87-5*0 Vinylvinylidene CH2CHCHC (g, triplet, cis) 695.5 689.1 ± 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) 1438.0 1432.3 ± 2.7 kJ/mol 52.0740 ± 0.0032 161054-20-2*2 Vinylvinylidene anion [CH2CHCHC]- (g) 405.8 399.1 ± 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 Hydrogen fluoride HF (aq, 55.51 H2O) -321.96 ± 0.10 kJ/mol 20.006343 ± 0.000070 7664-39-3*891 Chlorovinylidene CCHCl (g) 429.2 430.9 ± 2.9 kJ/mol 60.4820 ± 0.0018 70277-82-6*0 1,2-Butadien-1-ylidene CH3CHCC (g) 511.9 506.3 ± 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 Hydrogen iodide HI (aq, 3 H2O) -36.91 ± 0.56 kJ/mol 127.912410 ± 0.000076 10034-85-2*805 Hydrogen fluoride HF (aq, 75 H2O) -321.99 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*825 Methoxyethene CH2CHOCH3 (g, trans) -81.9 -99.0 ± 2.4 kJ/mol 58.0791 ± 0.0025 107-25-5*1 Hydrogen fluoride HF (aq, 10000 H2O) -325.42 ± 0.16 kJ/mol 20.006343 ± 0.000070 7664-39-3*850 Hydrogen chloride HCl (aq, 50 H2O) -165.186 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*822 Hydrogen iodide HI (aq, 20000 H2O) -56.730 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*852 Hydrogen bromide HBr (aq, 700 H2O) -120.04 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*835 Hydroperoxyimidogen HOON (g, cis) 111.9 109.0 ± 2.8 kJ/mol 47.01348 ± 0.00061 877456-58-1*2 Hydrogen fluoride HF (aq, 35 H2O) -321.91 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*904 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, 800 H2O) -120.06 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*837 Cyanoamidogen anion [HNCN]- (g, t-triplet) 392.4 390.4 ± 6.2 kJ/mol 41.03267 ± 0.00082 67131-47-9*11 Fluoromethane cation [CH3F]+ (g) 981.81 974.32 ± 0.62 kJ/mol 34.03237 ± 0.00083 59122-96-2*0 Ethoxyethene CH2CHOCH2CH3 (g) -117.8 -136.3 ± 1.5 kJ/mol 72.1057 ± 0.0033 109-92-2*0 Nitric acid HON(O)O (aq, 555.1 H2O) -206.17 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*895 Hydroxymethylene anion [HCOH]- (g) 147.2 144.2 ± 1.6 kJ/mol 30.02653 ± 0.00087 207914-87-2*0 1-Buten-3-yn-1-yl HCCCHCH (g) 547.40 544.89 ± 0.85 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) 419.9 419.3 ± 1.2 kJ/mol 51.0672 ± 0.0032 119611-65-3*0 Hydrogen bromide HBr (aq, 900 H2O) -120.08 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*838 1-Iminoethyl CH3CNH (g) 233.1 223.0 ± 1.1 kJ/mol 42.0599 ± 0.0016 128365-64-0*0 Hydrogen iodide HI (aq, 50000 H2O) -56.764 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*855 Dioxyamidogen HNOO (g, trans) 251.1 244.6 ± 2.5 kJ/mol 47.01348 ± 0.00061 71843-95-3*1 Fluoromethane CH3F (l) -245.75 ± 0.45 kJ/mol 34.03292 ± 0.00083 593-53-3*590 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, 500 H2O) -56.358 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*833 Dioxodiazoxane ONONO (g) 93.0 88.1 ± 1.3 kJ/mol 76.01168 ± 0.00091 122413-35-8*0 Propylidene CH3CH2CH (g, singlet TS) 355.7 340.8 ± 2.0 kJ/mol 42.0797 ± 0.0024 6700-78-3*2 1-Iminoethyl CH3CNH (g, syn) 252.4 242.4 ± 2.0 kJ/mol 42.0599 ± 0.0016 128365-64-0*1 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 1-Iminoethylium [CH3CNH]+ (g) 833.7 823.2 ± 3.0 kJ/mol 42.0594 ± 0.0016 *128365-64-0*0 Hydrobromate ion [HBr]- (g) -5.5 -12.0 ± 4.3 kJ/mol 80.9125 ± 0.0010 85532-97-4*0 1-Iminoethylium [CH3CNH]+ (g, triplet) 1342.2 1333.3 ± 3.9 kJ/mol 42.0594 ± 0.0016 *128365-64-0*1 2-Cyclopropen-1-ylidenemethylium [CHC(CHCH)]+ (g) 1346.5 1343.9 ± 1.8 kJ/mol 51.0661 ± 0.0032 112936-36-4*0 Ammonium hydroxide NH4OH (aq, 12 H2O) -366.07 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*816 Ethylperoxy CH3CH2OO (g) -6.23 -22.20 ± 0.64 kJ/mol 61.0599 ± 0.0017 3170-61-4*0 Formic acid HC(O)OH (aq, 50000 H2O) -425.39 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*855 1-Iminoethylium [CH3CNH]+ (g, syn-triplet) 1378.3 1368.8 ± 4.3 kJ/mol 42.0594 ± 0.0016 *128365-64-0*11 1,3-Cyclobutadien-1-ylium [C(CHCHCH)]+ (g) 1388.4 1383.4 ± 1.8 kJ/mol 51.0661 ± 0.0032 81913-77-1*0 Nitric acid HON(O)O (aq, 2000 H2O) -206.30 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*841 Carbonylbis(oxy) OC(O)O (g) -144.7 -145.7 ± 2.4 kJ/mol 60.0089 ± 0.0012 16518-45-9*0 1-Iminoethanide [CH3CNH]- (g) 185.7 175.6 ± 3.2 kJ/mol 42.0604 ± 0.0016 *128365-65-1*0 Cyclobutenide [CH2(CHCHCH)]- (g) 320.4 307.9 ± 3.2 kJ/mol 53.0830 ± 0.0032 60211-42-9*0 Hydrogen fluoride HF (aq, 3000 H2O) -323.83 ± 0.12 kJ/mol 20.006343 ± 0.000070 7664-39-3*842 Chloromethane CH3Cl (l) -106.51 -102.55 ± 0.19 kJ/mol 50.4872 ± 0.0012 74-87-3*590 1-Iminoethanide [CH3CNH]- (g, syn) 193.2 182.6 ± 3.6 kJ/mol 42.0604 ± 0.0016 *128365-65-1*1 Ethoxyoxoniumylidene [CH3CH2OO]+ (g) 923.8 911.4 ± 1.5 kJ/mol 61.0594 ± 0.0017 268728-77-4*0 Phenylperoxy cation [C6H5OO]+ (g) 1018.9 1001.9 ± 3.1 kJ/mol 109.1022 ± 0.0049 956036-17-2*0 Phenylperoxy anion [C6H5OO]- (g) -38.9 -55.9 ± 3.3 kJ/mol 109.1032 ± 0.0049 *956036-17-2*0 Ethoxyoxoniumylidene [CH3CH2OO]+ (g, singlet) 962.4 947.7 ± 1.7 kJ/mol 61.0594 ± 0.0017 268728-77-4*2 Bromine atom Br (g, 2P1/2) 162.009 155.947 ± 0.055 kJ/mol 79.90400 ± 0.00100 10097-32-2*2 Hydrogen fluoride HF (aq, 5000 H2O) -324.43 ± 0.14 kJ/mol 20.006343 ± 0.000070 7664-39-3*844 Ethoxyethene CH2CHOCH2CH3 (g, cis-perp) -111.3 -135.2 ± 2.3 kJ/mol 72.1057 ± 0.0033 109-92-2*21 1,2-Butadiene CH3CHCCH2 (cr,l) 137.81 138.87 ± 0.63 kJ/mol 54.0904 ± 0.0032 590-19-2*500 Fulvene cation [CH2C(CHCHCHCH)]+ (g) 1043.6 1027.9 ± 2.7 kJ/mol 78.1113 ± 0.0048 34504-75-1*0 Fulvene anion [CH2C(CHCHCHCH)]- (g) 191.4 176.3 ± 4.0 kJ/mol 78.1124 ± 0.0048 34504-63-7*0 Ammonium hydroxide NH4OH (aq, 15 H2O) -366.13 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*817 Ethoxyoxoniumylidene [CH3CH2OO]+ (g, gauche singlet) 967.4 951.5 ± 2.4 kJ/mol 61.0594 ± 0.0017 268728-77-4*23 Hydrogen chloride HCl (aq, 50000 H2O) -166.922 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*855 Ethaneperoxolate [CH3CH2OO]- (g) -120.47 -136.53 ± 0.72 kJ/mol 61.0604 ± 0.0017 268728-75-2*0 Oxonium [H3O]+ (g, ortho) 605.95 599.14 ± 0.17 kJ/mol 19.02267 ± 0.00037 13968-08-6*1 Fulvenone cation [OCC(CHCHCHCH)]+ (g) 913.5 903.3 ± 1.9 kJ/mol 92.0948 ± 0.0048 884319-80-6*0 Bromomethane cation [CH3Br]+ (g) 996.59 981.67 ± 0.21 kJ/mol 94.9380 ± 0.0013 12538-70-4*0 Hydrogen chloride HCl (aq, 20000 H2O) -166.885 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*852 Diazirinyl HC(NN) (g) 491.08 487.69 ± 0.96 kJ/mol 41.03212 ± 0.00082 69967-71-1*0 Iodomethane cation [CH3I]+ (g) 944.71 935.31 ± 0.18 kJ/mol 141.93844 ± 0.00083 12538-72-6*0 Silicon atom tetracation [Si]+4 (g) 10401.08 10404.06 ± 0.56 kJ/mol 28.08331 ± 0.00030 22537-24-2*0 Silicon anion Si- (g) 316.26 319.24 ± 0.56 kJ/mol 28.08605 ± 0.00030 14337-02-1*0 Trihydrogen H(HH) (g, TS) 477.4 474.7 ± 2.3 kJ/mol 3.02382 ± 0.00021 12184-91-7*201 Ethoxyethene CH2CHOCH2CH3 (g, trans-trans) -110.8 -133.0 ± 2.6 kJ/mol 72.1057 ± 0.0033 109-92-2*1 Disilicon anion [Si2]- (g) 375.1 379.0 ± 1.7 kJ/mol 56.17155 ± 0.00060 64236-73-3*0 Nitrato [ON(O)O]+ (g) 1290.59 1285.88 ± 0.86 kJ/mol 62.00439 ± 0.00090 133057-96-2*0 Tetraoxidanyl HOOOO (g, trans) 76.7 69.5 ± 6.1 kJ/mol 65.0055 ± 0.0012 69696-93-1*1 N-Methylenemethaniminium [CH2NCH2]+ (g) 904.4 893.4 ± 3.1 kJ/mol 42.0594 ± 0.0016 88333-01-1*0 Ethaneperoxolate [CH3CH2OO]- (g, trans) -119.9 -135.6 ± 1.9 kJ/mol 61.0604 ± 0.0017 268728-75-2*1 N-Methylenemethaniminium [CH2NCH2]+ (g, triplet) 1157.2 1147.3 ± 4.0 kJ/mol 42.0594 ± 0.0016 88333-01-1*1 Trichlorine cation [Cl3]+ (g) 1056.6 1055.5 ± 1.4 kJ/mol 106.3576 ± 0.0027 33088-85-6*0 Fluoronitrate [NF]- (g) 211.3 211.5 ± 2.8 kJ/mol 33.005692 ± 0.000070 33088-90-3*0 Hydrogen iodide HI (aq, 555.1 H2O) -56.379 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*895 Fluoroform CHF3 (l) -704.70 ± 0.42 kJ/mol 70.01385 ± 0.00080 75-46-7*590 Acetic acid CH3C(O)OH (aq, 111 H2O) -484.67 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*892 Formic acid HC(O)OH (aq, 1000 H2O) -425.35 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*839 Diazirenide [HC(NN)]- (g, triplet) 504.8 501.3 ± 2.9 kJ/mol 41.03267 ± 0.00082 130614-84-5*1 Silicon carbide anion [SiC]- (g) 509.8 514.4 ± 4.4 kJ/mol 40.09675 ± 0.00085 86017-99-4*0 Ethane anion [CH3CH3]- (g) 41.9 26.6 ± 4.4 kJ/mol 30.0696 ± 0.0017 54064-82-3*0 N-Methylidynemethanaminium [CH3NCH]+ (g) 881.1 870.3 ± 3.0 kJ/mol 42.0594 ± 0.0016 64709-60-0*0 Silicon carbide SiC (cr,l) -70.5 -71.5 ± 1.5 kJ/mol 40.09620 ± 0.00085 409-21-2*500 2-Butynylium [CH3CCCH2]+ (g) 1085.9 1077.6 ± 1.3 kJ/mol 53.0820 ± 0.0032 64235-83-2*0 Ethoxyethene CH2CHOCH2CH3 (g, trans-perp) -108.8 -132.0 ± 2.3 kJ/mol 72.1057 ± 0.0033 109-92-2*11 Isocyanogen chloride cation [ClNC]+ (g) 1481.0 1482.2 ± 3.9 kJ/mol 61.4696 ± 0.0012 956475-91-5*0 Trifluorosilyl anion [SiF3]- (g) -1225.9 -1229.2 ± 3.4 kJ/mol 85.08126 ± 0.00030 54711-93-2*0 Iminomethide [HCNH]- (g) 237.4 233.6 ± 1.8 kJ/mol 28.03387 ± 0.00082 90623-30-6*0 Difluorosilylene anion [SiF2]- (g) -653.0 -653.3 ± 3.4 kJ/mol 66.08285 ± 0.00030 145089-80-1*0 Difluorosilylene SiF2 (g) -629.3 -630.1 ± 1.3 kJ/mol 66.08231 ± 0.00030 13966-66-0*0 Difluorosilylene SiF2 (g, triplet) -314.5 -315.1 ± 1.3 kJ/mol 66.08231 ± 0.00030 13966-66-0*1 Chlorous acid cation [HOClO]+ (g) 996.6 991.6 ± 3.1 kJ/mol 68.4589 ± 0.0011 *99559-66-7*0 (Methylimino)methyl CH3NCH (g) 278.0 267.9 ± 1.1 kJ/mol 42.0599 ± 0.0016 117928-23-1*0 (Methylimino)methyl CH3NCH (g, cis) 297.1 287.1 ± 2.0 kJ/mol 42.0599 ± 0.0016 117928-23-1*2 1-Hydroperoxyethylium [CH3CHOOH]+ (g) 690.5 675.6 ± 1.5 kJ/mol 61.0594 ± 0.0017 *126898-98-4*0 Fluorosilylidyne SiF (g, quartet) 297.24 298.46 ± 0.62 kJ/mol 47.08390 ± 0.00030 11128-24-8*2 Hydrogen iodide HI (aq, 12 H2O) -54.02 ± 0.17 kJ/mol 127.912410 ± 0.000076 10034-85-2*816 Chlorous acid anion [HOClO]- (g) -154.3 -156.1 ± 3.3 kJ/mol 68.4600 ± 0.0011 99559-66-7*0 (Methylimino)methanide [CH3NCH]- (g) 223.0 212.2 ± 3.2 kJ/mol 42.0604 ± 0.0016 *64709-60-0*0 1-Hydroperoxyethylium [CH3CHOOH]+ (g, triplet) 841.4 830.1 ± 1.7 kJ/mol 61.0594 ± 0.0017 *126898-98-4*1 (Methylimino)methanide [CH3NCH]- (g, cis) 236.6 225.7 ± 3.6 kJ/mol 42.0604 ± 0.0016 *64709-60-0*2 1-Hydroperoxyethylium [CH3CHOOH]+ (g, cis singlet) 691.8 676.1 ± 2.3 kJ/mol 61.0594 ± 0.0017 *126898-98-4*22 Hydrogen iodide HI (aq, 6 H2O) -49.965 ± 0.096 kJ/mol 127.912410 ± 0.000076 10034-85-2*811 Nitrous oxide NNO (aq, undissoc) 61.42 ± 0.11 kJ/mol 44.01288 ± 0.00033 10024-97-2*1000 1-Hydroperoxyethylium [CH3CHOOH]+ (g, cis triplet) 843.7 831.6 ± 2.6 kJ/mol 61.0594 ± 0.0017 *126898-98-4*12 Ammonium hydroxide NH4OH (aq, 800 H2O) -366.38 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*837 Silylene SiH2 (g) 271.59 269.92 ± 0.81 kJ/mol 30.10138 ± 0.00033 13825-90-6*0 Dinitrogen tetraoxide O2NNO2 (cr,l) -37.85 -27.00 ± 0.19 kJ/mol 92.0111 ± 0.0012 10544-72-6*500 Hydrogen iodide HI (aq, 4 H2O) -44.15 ± 0.30 kJ/mol 127.912410 ± 0.000076 10034-85-2*807 2-Hydroperoxyethyl CH2CH2OOH (g) 64.6 51.3 ± 1.3 kJ/mol 61.0599 ± 0.0017 126898-97-3*0 Disilane cation [SiH3SiH3]+ (g) 1030.2 1017.4 ± 2.2 kJ/mol 62.21809 ± 0.00073 96301-43-8*0 Hydrogen chloride HCl (aq, 700 H2O) -166.487 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*835 1-Aminoethenylium [CH2CNH2]+ (g) 900.0 889.2 ± 3.0 kJ/mol 42.0594 ± 0.0016 *139597-26-5*0 Isocyanogen chloride anion [ClNC]- (g) 102.9 107.4 ± 3.9 kJ/mol 61.4707 ± 0.0012 923019-39-0*0 Bromoform CHBr3 (l) 8.2 ± 1.1 kJ/mol 252.7306 ± 0.0031 75-25-2*590 1-Aminoethenide [CH2CNH2]- (g) 216.0 205.2 ± 3.2 kJ/mol 42.0604 ± 0.0016 139597-26-5*0 Acetic acid CH3C(O)OH (aq, 200 H2O) -484.73 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*830 2-Hydroperoxyethyl CH2CH2OOH (g, gauche) 64.6 50.9 ± 1.3 kJ/mol 61.0599 ± 0.0017 126898-97-3*3 Difluoromethane CH2F2 (l) -468.91 ± 0.37 kJ/mol 52.02339 ± 0.00081 75-10-5*590 Disilene SiH2SiH2 (g) 288.8 280.1 ± 1.7 kJ/mol 60.20276 ± 0.00066 15435-77-5*0 1-Methylene-2-propenylium [CH2CHCCH2]+ (g) 1059.5 1049.4 ± 1.7 kJ/mol 53.0820 ± 0.0032 62698-26-4*0 Ammonium hydroxide NH4OH (aq, 25 H2O) -366.24 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*819 Ethenol CH2CHOH (g) -113.31 -123.66 ± 0.38 kJ/mol 44.0526 ± 0.0017 557-75-5*0 Acetic acid CH3C(O)OH (aq, 300 H2O) -484.76 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*831 Silylsilylene SiH3SiH (g) 317.3 309.5 ± 1.9 kJ/mol 60.20276 ± 0.00066 50420-90-1*0 Acetic acid CH3C(O)OH (aq, 400 H2O) -484.77 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*832 Hydrogen bromide HBr (aq, 30 H2O) -118.59 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*820 Acetylide [C2]-2 (g) 843.0 849.6 ± 3.2 kJ/mol 24.0225 ± 0.0016 34846-56-5*0 2-Hydroperoxyethyl CH2CH2OOH (g, anti) 65.1 51.6 ± 2.2 kJ/mol 61.0599 ± 0.0017 126898-97-3*1 Iodoniumyl [HI]+ (g) 1030.73 1028.56 ± 0.11 kJ/mol 127.911861 ± 0.000076 12298-17-8*0 Peroxychlorous acid HOOClO (g, perp ?) 101.5 95.4 ± 3.6 kJ/mol 84.4588 ± 0.0013 177778-92-6*3 Acetic acid CH3C(O)OH (aq, 500 H2O) -484.79 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*833 Acetic acid CH3C(O)OH (aq, 555.1 H2O) -484.79 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*895 Di-mu-hydrodihydrodisilicon HSi(HSiHH) (g) 374.7 364.5 ± 2.3 kJ/mol 60.20276 ± 0.00066 129970-82-7*0 Di-mu-hydrodihydrodisilicon HSi(HSiHH) (g, trans) 374.7 364.3 ± 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) 1180.2 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 2-Hydroperoxyethyl CH2CH2OOH (g, gauche-anti) 65.5 51.5 ± 2.2 kJ/mol 61.0599 ± 0.0017 126898-97-3*31 Acetic acid CH3C(O)OH (aq, 600 H2O) -484.79 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*834 Hydrogen bromide HBr (aq, 1000 H2O) -120.11 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*839 Hydrogen chloride HCl (aq, 800 H2O) -166.516 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*837 Ammonium hydroxide NH4OH (aq, 4000 H2O) -366.32 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*843 1-Methylethylidene CH3CCH3 (g) 316.08 303.18 ± 0.97 kJ/mol 42.0797 ± 0.0024 40852-89-9*0 Chlorine chlorite ClOClO (g) 168.6 166.4 ± 1.3 kJ/mol 102.9042 ± 0.0019 105206-44-8*0 Hydrogen chloride HCl (aq, 3500 H2O) -166.752 ± 0.024 kJ/mol 36.46064 ± 0.00090 7647-01-0*899 2-Aminoethenyl CHCHNH2 (g) 319.8 310.2 ± 1.3 kJ/mol 42.0599 ± 0.0016 176964-54-8*0 2-Hydroperoxyethyl CH2CH2OOH (g, anti-syn) 65.6 52.0 ± 2.2 kJ/mol 61.0599 ± 0.0017 126898-97-3*12 Tetroxidane HOOOOH (g, C2 II) -30.97 -41.42 ± 0.64 kJ/mol 66.0135 ± 0.0012 29683-94-1*23 Ethenyldioxy CH2CHOO (g) 118.7 109.8 ± 1.3 kJ/mol 59.0440 ± 0.0017 88181-72-0*0 Hydrogen bromide HBr (aq, 1500 H2O) -120.17 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*840 2-Aminoethenylium [CHCHNH2]+ (g, triplet) 1110.6 1099.9 ± 2.4 kJ/mol 42.0594 ± 0.0016 64724-21-6*1 Nitric acid HON(O)O (aq, 50 H2O) -206.04 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*822 Ammonium hydroxide NH4OH (aq, 30 H2O) -366.26 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*820 Ammonium hydroxide NH4OH (aq, 40 H2O) -366.31 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*821 2-Aminoethenyl anion [CHCHNH2]- (g) 230.2 219.5 ± 2.6 kJ/mol 42.0604 ± 0.0016 *64724-21-6*0 Isoformyl anion [COH]- (g) 55.7 58.4 ± 1.8 kJ/mol 29.01859 ± 0.00086 81747-63-9*0 Hydrogen bromide HBr (aq, 2000 H2O) -120.21 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*841 Hydrogen fluoride HF (aq, 264.3 H2O) -322.13 ± 0.10 kJ/mol 20.006343 ± 0.000070 7664-39-3*909 Hypochloroperoxoous acid, hydroxy ester HOOOCl (g) 48.4 41.6 ± 1.8 kJ/mol 84.4588 ± 0.0013 928652-99-7*0 Hydrogen chloride HCl (aq, 3000 H2O) -166.738 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*842 Hydrogen chloride HCl (aq, 900 H2O) -166.541 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*838 Acetic acid CH3C(O)OH (aq, 700 H2O) -484.80 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*835 Hydrogen iodide HI (aq, 600 H2O) -56.391 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*834 Hydrogen bromide HBr (aq, 2500 H2O) -120.24 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*898 Hydrogen bromide HBr (aq, 40 H2O) -118.90 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*821 Formic acid HC(O)OH (aq, 100000 H2O) -425.42 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*861 Hydroxysilyl anion [SiH2OH]- (g) -219.3 -227.0 ± 2.1 kJ/mol 47.10927 ± 0.00047 78450-47-2*0 Hydroxysilyl anion [SiH2OH]- (g, anti) -219.0 -226.8 ± 2.7 kJ/mol 47.10927 ± 0.00047 78450-47-2*2 Hydrogen bromide HBr (aq, 4000 H2O) -120.29 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*843 1,2-Butadienylium [CH3CHCCH]+ (g) 1099.2 1089.9 ± 1.2 kJ/mol 53.0820 ± 0.0032 *65114-67-2*0 Ammonium hydroxide NH4OH (aq, 55.51 H2O) -366.33 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*891 Ethylimidogen anion [CH3CH2N]- (g) 277.3 263.4 ± 3.6 kJ/mol 43.0684 ± 0.0016 82539-33-1*0 Benzvalene cation [((CHCH)(CH(CHCH)CH))]+ (g) 1200.3 1184.8 ± 2.7 kJ/mol 78.1113 ± 0.0048 81050-63-7*0 Vinyl alcohol cation [CH2CHOH]+ (g) 778.6 767.7 ± 1.3 kJ/mol 44.0520 ± 0.0017 57239-63-1*0 Ethylimidogen cation [CH3CH2N]+ (g, quartet) 1394.6 1381.4 ± 3.6 kJ/mol 43.0673 ± 0.0016 *82539-33-1*1 Nitrosyl nitrate ONONO2 (g) 48.3 40.4 ± 1.8 kJ/mol 92.0111 ± 0.0012 15969-55-8*0 1-Aziridinylium [N(CH2CH2)]+ (g, triplet) 1265.8 1254.2 ± 3.1 kJ/mol 42.0594 ± 0.0016 91127-35-4*1 Vinylcyclopentadienylium [CH2CHC(CHCHCHCH)]+ (g) 1076.8 1059.4 ± 3.7 kJ/mol 91.1299 ± 0.0056 146893-89-2*0 Hydrogen iodide HI (aq, 7000 H2O) -56.668 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*846 Ethenyldioxy CH2CHOO (g, syn) 122.9 113.2 ± 2.2 kJ/mol 59.0440 ± 0.0017 88181-72-0*2 1-Aziridinide [N(CH2CH2)]- (g) 244.1 231.8 ± 3.3 kJ/mol 42.0604 ± 0.0016 1358579-49-3*0 Ammonium hydroxide NH4OH (aq, 75 H2O) -366.35 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*825 Hydrogen iodide HI (aq, 3000 H2O) -56.601 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*842 Hydrogen chloride HCl (aq, 12 H2O) -162.010 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*816 Butadienylacetylene CH2CHCHCHCCH (g) 358.9 346.4 ± 1.9 kJ/mol 78.1118 ± 0.0048 10420-90-3*0 Cyanoamidogen HNCN (g, quartet) 652.4 650.3 ± 1.2 kJ/mol 41.03212 ± 0.00082 12347-01-2*2 (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) 361.9 350.7 ± 1.9 kJ/mol 78.1118 ± 0.0048 821-08-9*0 Formic acid HC(O)OH (aq, 900 H2O) -425.35 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*838 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 2-Methyl-2-propanol (CH3)3COH (cr,l) -341.1 -365.5 ± 1.9 kJ/mol 74.1216 ± 0.0033 75-65-0*500 Biallenyl CH2CCHCHCCH2 (g, cis) 419.5 408.2 ± 2.3 kJ/mol 78.1118 ± 0.0048 29776-96-3*2 Propargylallene CH2CCHCH2CCH (g) 431.4 420.1 ± 1.4 kJ/mol 78.1118 ± 0.0048 33142-15-3*0 Nitric acid HON(O)O (aq, 5000 H2O) -206.37 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*844 Propargylallene CH2CCHCH2CCH (g, cis) 432.3 420.7 ± 2.2 kJ/mol 78.1118 ± 0.0048 33142-15-3*2 Oxoniumyl ion [H2O]+ (g, para) 978.744 975.593 ± 0.024 kJ/mol 18.01473 ± 0.00033 56583-62-1*2 Diazene cation [HNNH]+ (g, trans-iso-cis equilib) 1132.53 1125.87 ± 0.64 kJ/mol 30.02881 ± 0.00020 76986-17-9*0 3-Methylene-1-penten-4-yne CH2CHC(CH2)CCH (g) 362.6 350.3 ± 2.2 kJ/mol 78.1118 ± 0.0048 6929-96-0*0 3-Methylene-1-penten-4-yne CH2CHC(CH2)CCH (g, gauche) 374.8 362.4 ± 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 Ketene CH2CO (g, ortho singlet) -45.21 -48.39 ± 0.11 kJ/mol 42.0367 ± 0.0016 463-51-4*22 1,2,3,5-Hexatetraene CH2CCCHCHCH2 (g, cis) 400.6 389.0 ± 2.3 kJ/mol 78.1118 ± 0.0048 60239-33-0*2 2-Aziridinyl NH(CHCH2) (g) 361.0 349.5 ± 1.7 kJ/mol 42.0599 ± 0.0016 *23838-09-7*0 Cyanoaminylium [HNCN]+ (g) 1363.1 1360.8 ± 1.3 kJ/mol 41.03157 ± 0.00082 205443-18-1*0 Acetic acid CH3C(O)OH (aq, 800 H2O) -484.80 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*837 Acetic acid CH3C(O)OH (aq, 900 H2O) -484.80 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*838 2-Aziridinylium [NH(CHCH2)]+ (g) 1010.9 998.9 ± 3.3 kJ/mol 42.0594 ± 0.0016 *91127-35-4*0 Vinylcyclopentadienylium [CH2CHC(CHCHCHCH)]+ (g, triplet) 1099.3 1081.4 ± 4.5 kJ/mol 91.1299 ± 0.0056 146893-89-2*1 Nitrilomethylimidogen NCHN (g) 581.6 578.4 ± 1.5 kJ/mol 41.03212 ± 0.00082 324529-58-0*0 Ammonium hydroxide NH4OH (aq, 200 H2O) -366.37 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*830 1,3-Butadienyl CH2CHCHCH (g) 372.28 363.06 ± 0.87 kJ/mol 53.0825 ± 0.0032 86181-68-2*0 Hydrazoic acid anion [HNNN]- (g) 309.1 303.2 ± 2.3 kJ/mol 43.02871 ± 0.00022 203264-98-6*0 Aminomethylidyne anion [CNH2]- (g, triplet) 481.6 478.1 ± 3.2 kJ/mol 28.03387 ± 0.00082 96808-04-7*1 Difluorodioxidanium [FOOF]+ (g) 1283.7 1280.1 ± 2.3 kJ/mol 69.99506 ± 0.00060 *7783-44-0*0 Cyanogen bromide cation [BrCN]+ (g) 1331.3 1325.0 ± 1.4 kJ/mol 105.9209 ± 0.0013 34749-77-4*0 1-Methylallyl CH3CHCHCH2 (g) 152.68 136.21 ± 0.79 kJ/mol 55.0984 ± 0.0032 15819-46-2*0 2-Aziridinylium [NH(CHCH2)]+ (g, triplet) 1305.0 1293.2 ± 4.1 kJ/mol 42.0594 ± 0.0016 *91127-35-4*1 Hydrogen iodide HI (aq, 1250 H2O) -56.496 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*954 1-Methyl-1-propenyl CH3CCHCH3 (g) 240.12 224.73 ± 0.66 kJ/mol 55.0984 ± 0.0032 71790-71-1*0 Hydrogen iodide HI (aq, 2000 H2O) -56.555 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*841 1-Methyl-1-propenyl CH3CCHCH3 (g, cis) 243.4 227.1 ± 1.9 kJ/mol 55.0984 ± 0.0032 71790-71-1*2 Hydrogen iodide HI (aq, 700 H2O) -56.412 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*835 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-Butenyl CH3CH2CHCH (g) 263.47 246.42 ± 0.68 kJ/mol 55.0984 ± 0.0032 2669-61-6*0 Hydrazoic acid HNNN (cr,l) 261.57 ± 0.64 kJ/mol 43.02816 ± 0.00022 7782-79-8*500 1-Butenyl CH3CH2CHCH (g, gauche) 263.9 246.6 ± 1.9 kJ/mol 55.0984 ± 0.0032 2669-61-6*3 Nitric acid HON(O)O (aq, 2 H2O) -193.75 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*803 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 Acetic acid CH3C(O)OH (aq, 1000 H2O) -484.81 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*839 2-Aziridinylium [NH(CHCH2)]+ (g, syn-triplet) 1335.0 1323.9 ± 4.8 kJ/mol 42.0594 ± 0.0016 *91127-35-4*11 Hydrogen bromide HBr (aq, 50 H2O) -119.11 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*822 2-Aziridinide [NH(CHCH2)]- (g) 316.2 304.1 ± 3.4 kJ/mol 42.0604 ± 0.0016 111127-93-6*0 1,2-Pentadien-4-ynylidene HCCCHCC (g) 791.3 794.0 ± 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 2-Aziridinide [NH(CHCH2)]- (g, syn) 330.2 318.1 ± 4.0 kJ/mol 42.0604 ± 0.0016 111127-93-6*1 1,3-Butadienyl CH2CHCHCH (g, trans-cis) 374.9 364.5 ± 1.9 kJ/mol 53.0825 ± 0.0032 86181-68-2*12 Ethylamine CH3CH2NH2 (cr,l) -76.80 ± 0.67 kJ/mol 45.0837 ± 0.0017 75-04-7*500 Propylidene CH3CH2CH (g, singlet TS syn) 362.8 347.5 ± 2.8 kJ/mol 42.0797 ± 0.0024 6700-78-3*22 Methylaminyliumyl [CH3N]+ (g ?) 1388.2 1381.9 ± 2.2 kJ/mol 29.04071 ± 0.00083 56924-51-7*0 Hydrogen chloride HCl (aq, 5000 H2O) -166.793 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*844 Ammonium hydroxide NH4OH (aq, 300 H2O) -366.38 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*831 Hydrogen peroxide HOOH (g, ortho) -129.401 -135.407 ± 0.058 kJ/mol 34.01468 ± 0.00062 7722-84-1*1 1-Aminoethyl anion [CH3CHNH2]- (g) 174.5 157.0 ± 3.2 kJ/mol 44.0763 ± 0.0017 59263-55-7*0 Ammonium hydroxide NH4OH (aq, 400 H2O) -366.39 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*832 Water H2O (g, ortho) -238.620 -241.807 ± 0.022 kJ/mol 18.01528 ± 0.00033 7732-18-5*1 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 1079.1 ± 2.9 kJ/mol 44.0752 ± 0.0017 54387-08-5*12 Hydrogen iodide HI (aq, 800 H2O) -56.433 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*837 1,3-Propanediyl CH2CH2CH2 (g) 319.3 307.9 ± 1.3 kJ/mol 42.0797 ± 0.0024 32458-33-6*0 Hydrogen bromide HBr (aq, 7000 H2O) -120.34 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*846 Difluorodioxidane anion [FOOF]- (g) -251. -251. ± 28. kJ/mol 69.99615 ± 0.00060 *7783-45-1*0 N-Methylethanamine CH3CH2NHCH3 (cr,l) -74.9 ± 2.3 kJ/mol 59.1103 ± 0.0025 624-78-2*500 1,3-Butadienyl CH2CHCHCH (g, cis-trans) 384.1 374.5 ± 1.9 kJ/mol 53.0825 ± 0.0032 86181-68-2*21 1,3-Butadienyl CH2CHCHCH (g, gauche-cis) 385.6 375.4 ± 1.9 kJ/mol 53.0825 ± 0.0032 86181-68-2*22 Hydrogen chloride HCl (aq, 10 H2O) -161.148 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*815 2-Methyl-2-propanamine (CH3)3CNH2 (l) -150.60 ± 0.53 kJ/mol 73.1369 ± 0.0033 75-64-9*590 Nitric acid HON(O)O (aq, 55.51 H2O) -206.03 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*891 Formic acid cation [HC(O)OH]+ (g) 721.95 715.42 ± 0.25 kJ/mol 46.0248 ± 0.0010 50614-05-6*0 Hydrogen fluoride HF (aq, 25 H2O) -321.86 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*819 Naphtalene cation [C6H4(C4H4)]+ (g) 956.97 933.89 ± 0.55 kJ/mol 128.1700 ± 0.0080 34512-27-1*0 Naphtalene anion [C6H4(C4H4)]- (g) 187.7 164.8 ± 3.0 kJ/mol 128.1711 ± 0.0080 34509-91-6*0 Carbon C (g, quintuplet) 1114.963 1120.109 ± 0.040 kJ/mol 12.01070 ± 0.00080 7440-44-0*3 Formic acid anion [HC(O)OH]- (g) -256.2 -262.3 ± 1.8 kJ/mol 46.0259 ± 0.0010 19066-82-1*0 Acetic acid CH3C(O)OH (aq, 2000 H2O) -484.82 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*841 Nitric acid HON(O)O (aq, 4 H2O) -200.29 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*807 Acetic acid CH3C(O)OH (aq, 5000 H2O) -484.70 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*844 (Dimethylamino)methyl anion [(CH3)2NCH2]- (g) 190.9 166.6 ± 3.3 kJ/mol 58.1029 ± 0.0025 125231-49-4*0 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, 10000 H2O) -484.84 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*850 Water anion [H2O]- (g) -50.1 -53.0 ± 4.3 kJ/mol 18.01583 ± 0.00033 12259-30-2*0 Hydrogen bromide HBr (aq, 55.51 H2O) -119.18 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*891 Dicarbon monoxide CCO (g) 377.14 381.18 ± 0.83 kJ/mol 40.0208 ± 0.0016 12071-23-7*0 Nitric acid HON(O)O (aq, 100 H2O) -206.05 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*828 Formate [HC(O)O]- (aq) -425.47 ± 0.45 kJ/mol 45.0180 ± 0.0010 71-47-6*800 Ammonium hydroxide NH4OH (aq, 600 H2O) -366.38 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*834 1,3-Butadienylium [CH2CHCHCH]+ (g) 1133.7 1123.7 ± 2.5 kJ/mol 53.0820 ± 0.0032 86181-69-3*0 Isocyanic acid anion [HNCO]- (g) -54.2 -57.4 ± 3.0 kJ/mol 43.02533 ± 0.00086 *444010-28-0*0 Iminomethylimidogen anion [NCHN]- (g) 401.9 400.0 ± 2.3 kJ/mol 41.03267 ± 0.00082 150296-30-3*0 Cyanogen NCCN (cr,l) 273.96 289.20 ± 0.41 kJ/mol 52.0349 ± 0.0016 460-19-5*500 1-Propen-1-yl-3-ylidene CHCHCH (g) 656.8 653.3 ± 1.1 kJ/mol 39.0559 ± 0.0024 84654-90-0*0 1-Hydroxyethylidene CH3COH (g, singlet) 57.44 47.13 ± 0.77 kJ/mol 44.0526 ± 0.0017 30967-49-8*2 Hydrogen fluoride HF (aq, 300 H2O) -322.16 ± 0.10 kJ/mol 20.006343 ± 0.000070 7664-39-3*831 Benzophenone C6H5C(O)C6H5 (l) -24.8 ± 1.5 kJ/mol 182.2179 ± 0.0104 119-61-9*590 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, 20000 H2O) -484.85 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*852 Butadiynylium [CCCCH]+ (g) 1781.3 1787.8 ± 3.2 kJ/mol 49.0502 ± 0.0032 76108-67-3*0 Formic acid HC(O)OH (aq, 0.25 H2O) -424.94 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*924 Acetic acid CH3C(O)OH (aq, 50000 H2O) -484.86 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*855 Formic acid HC(O)OH (aq, 0.5 H2O) -425.15 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*923 Formic acid HC(O)OH (aq, 1 H2O) -425.43 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*801 Nitric acid HON(O)O (aq, 5 H2O) -201.95 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*809 Hydrogen fluoride HF (aq, 20000 H2O) -326.65 ± 0.16 kJ/mol 20.006343 ± 0.000070 7664-39-3*852 Helium He (g, singlet) -0.000 -0.000 ± 0.000 kJ/mol 4.0026020 ± 0.0000020 7440-59-7*2 Hydrogen peroxide cation [HOOH]+ (g) 897.30 890.31 ± 0.51 kJ/mol 34.01413 ± 0.00062 12325-10-9*0 Isocyanogen anion [CNCN]- (g) 386.6 388.7 ± 3.3 kJ/mol 52.0354 ± 0.0016 *83951-85-3*0 Helium dication [He]+2 (g) 7622.839 7622.839 ± 0.000 kJ/mol 4.0015048 ± 0.0000020 12587-46-1*0 Hydrogen fluoride HF (aq, 400 H2O) -322.26 ± 0.10 kJ/mol 20.006343 ± 0.000070 7664-39-3*832 Diiodine cation [I2]+ (g) 963.523 960.408 ± 0.018 kJ/mol 253.808391 ± 0.000060 28712-14-3*0 Hydrogen iodide HI (aq, 4000 H2O) -56.626 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*843 Tetrafluorohydrazine anion [NF2NF2]- (g, gauche) -184.5 -190.0 ± 3.3 kJ/mol 104.00764 ± 0.00014 39775-43-4*2 1-Propen-1-yl-3-ylidene CHCHCH (g, c-t quartet) 656.7 653.2 ± 2.0 kJ/mol 39.0559 ± 0.0024 84654-90-0*12 Dihelium He2 (g, singlet) 1761.349 1757.613 ± 0.018 kJ/mol 8.0052040 ± 0.0000040 12184-98-4*2 Formic acid HC(O)OH (aq, 1.5 H2O) -425.53 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*802 Hydrohelate [HeH]- (g) 143.256 139.027 ± 0.0021 kJ/mol 5.011091 ± 0.000070 12325-01-8*0 1,2-Difluoroethene CHFCHF (g) -302.99 -309.08 ± 0.83 kJ/mol 64.0341 ± 0.0016 1691-13-0*0 Hydrogen bromide HBr (aq, 2 H2O) -92.67 ± 0.13 kJ/mol 80.9119 ± 0.0010 10035-10-6*803 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 COC vdW (CO)(C) (g) 589.8 598.5 ± 1.5 kJ/mol 40.0208 ± 0.0016 *12071-24-8*0 Acetic acid CH3C(O)OH (aq, 100000 H2O) -484.87 ± 0.33 kJ/mol 60.0520 ± 0.0017 64-19-7*861 Diazomethyl HCNN (g) 467.85 465.30 ± 0.68 kJ/mol 41.03212 ± 0.00082 20813-32-5*0 Difluorovinylidene anion [CCF2]- (g) -88.2 -87.1 ± 2.3 kJ/mol 62.0188 ± 0.0016 107693-92-5*0 Isocyanogen bromide cation [BrNC]+ (g) 1470.0 1464.2 ± 5.9 kJ/mol 105.9209 ± 0.0013 238754-53-5*0 Dibromovinylidene CCBr2 (g) 510.6 499.5 ± 4.1 kJ/mol 183.8294 ± 0.0026 261771-36-2*0 Fluorovinylidene CCHF (g) 298.9 300.1 ± 3.1 kJ/mol 44.0277 ± 0.0016 70302-00-0*0 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 Diazomethyl HCNN (g, quartet) 652.7 649.8 ± 1.3 kJ/mol 41.03212 ± 0.00082 20813-32-5*2 Hydrogen bromide HBr (aq, 10 H2O) -115.90 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*815 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 Formic acid HC(O)OH (aq, 2 H2O) -425.50 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*803 Hydroneonate [NeH]- (g) 143.096 142.084 ± 0.035 kJ/mol 21.18819 ± 0.00060 75514-98-6*0 Diazomethyl HCNN (g, t-quartet) 653.0 650.0 ± 2.3 kJ/mol 41.03212 ± 0.00082 20813-32-5*21 Bromovinylidene CCHBr (g) 466.4 460.4 ± 3.8 kJ/mol 104.9333 ± 0.0019 161957-27-3*0 Formic acid HC(O)OH (aq, 2.5 H2O) -425.46 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*804 (E)-Difluorodiazene cation [FNNF]+ (g, trans) 1307.4 1302.3 ± 3.7 kJ/mol 66.00974 ± 0.00014 *13776-62-0*1 Krypton dication [Kr]+2 (g) 3701.124 3701.124 ± 0.013 kJ/mol 83.7989 ± 0.1000 18469-91-5*0 Diisocyanogen anion [CNNC]- (g) 456.8 462.5 ± 3.6 kJ/mol 52.0354 ± 0.0016 *78800-22-3*0 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, 3 H2O) -425.42 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*805 Nitric acid HON(O)O (aq, 7 H2O) -203.78 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*812 Diisocyanogen cation [CNNC]+ (g) 1825.3 1828.5 ± 3.2 kJ/mol 52.0343 ± 0.0016 *78800-21-2*0 Difluorophosgene anion [CF2O]- (g) -602.3 -604.2 ± 3.3 kJ/mol 66.00745 ± 0.00085 474815-26-4*0 Formic acid HC(O)OH (aq, 4 H2O) -425.35 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*807 Hydroxyamidogen HNOH (g) 101.28 94.45 ± 0.87 kJ/mol 32.02202 ± 0.00034 13940-32-4*0 1,3-Propanediyl CH2CH2CH2 (g, singlet TS) 337.7 323.0 ± 2.2 kJ/mol 42.0797 ± 0.0024 32458-33-6*2 1H-Diazirin-3-ylium [HN(NC)]+ (g) 1527.2 1523.7 ± 2.0 kJ/mol 41.03157 ± 0.00082 735234-64-7*0 Fluoro(fluorooxy)methylene FCOF (g) -134.8 -136.0 ± 1.3 kJ/mol 66.00691 ± 0.00085 479587-30-9*0 Sulfur atom hexacation [S]+6 (g) 26947.2 26949.0 ± 3.4 kJ/mol 32.0627 ± 0.0060 22537-26-4*0 Formic acid HC(O)OH (aq, 5 H2O) -425.30 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*809 Sulfur atom dianion [S]-2 (g) 454.0 455.8 ± 3.2 kJ/mol 32.0671 ± 0.0060 18496-25-8*0 Peroxychlorous acid HOOClO (g) 95.4 89.8 ± 2.0 kJ/mol 84.4588 ± 0.0013 177778-92-6*0 Disulfur cation [S2]+ (g) 1031.49 1032.08 ± 0.32 kJ/mol 64.1315 ± 0.0120 12597-02-3*0 Disulfur anion [S2]- (g) -34.06 -33.12 ± 0.52 kJ/mol 64.1325 ± 0.0120 12185-15-8*0 1-Hydroxyethylidene CH3COH (g) 57.44 47.13 ± 0.77 kJ/mol 44.0526 ± 0.0017 30967-49-8*0 Diazoethenylidene cation [NNCC]+ (g) 1771.1 1773.1 ± 3.5 kJ/mol 52.0343 ± 0.0016 *130760-10-0*0 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, 6 H2O) -425.25 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*811 Hydrogen bromide HBr (aq, 75 H2O) -119.36 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*825 Nitric acid HON(O)O (aq, 10 H2O) -205.01 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*815 Formic acid HC(O)OH (aq, 7 H2O) -425.22 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*812 Oxosulfate [SO]- (g) -102.66 -101.89 ± 0.50 kJ/mol 48.0659 ± 0.0060 12269-52-2*0 Trioxidane HOOOH (g) -81.75 -90.35 ± 0.40 kJ/mol 50.01408 ± 0.00091 14699-99-1*0 Sulfur trioxide cation [OS(O)O]+ (g) 847.65 844.74 ± 0.68 kJ/mol 80.0637 ± 0.0061 12710-95-1*0 Ammonium hydroxide NH4OH (aq, 700 H2O) -366.38 ± 0.41 kJ/mol 35.04584 ± 0.00047 1336-21-6*835 Sulfite [OS(O)O]-2 (g) -273.7 -279.3 ± 4.2 kJ/mol 80.0653 ± 0.0061 14265-45-3*0 Diazoethenylidene anion [NNCC]- (g) 529.6 532.2 ± 3.5 kJ/mol 52.0354 ± 0.0016 *130760-11-1*0 Nitrosodioxaziridine ONN(OO) (g, gauche) 415.3 409.5 ± 2.8 kJ/mol 76.01168 ± 0.00091 132871-99-9*3 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, 8 H2O) -425.20 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*813 Sulfur oxide peroxide OSOO (g, trans) -3.4 -7.1 ± 3.0 kJ/mol 80.0642 ± 0.0061 175799-68-5*1 1,1-Ethenediol CH2C(OH)2 (g) -307.56 -320.10 ± 0.83 kJ/mol 60.0520 ± 0.0017 10375-04-9*0 Hydrogen chloride HCl (aq, 7000 H2O) -166.822 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*846 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 Trioxodinitrate anion [ONN(O)O]- (g) -104.2 -107.5 ± 1.9 kJ/mol 76.01223 ± 0.00091 194856-62-7*0 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 -233.56 ± 0.87 kJ/mol 80.1319 ± 0.0120 12143-07-6*0 1,1-Ethenediol CH2C(OH)2 (g, syn-syn C2v) -302.3 -315.7 ± 1.9 kJ/mol 60.0520 ± 0.0017 10375-04-9*2 1H-diazirin-3-ide [HN(NC)]- (g) 379.8 376.7 ± 2.0 kJ/mol 41.03267 ± 0.00082 *735234-64-7*0 Sulfoniumyl [H2S]+ (g) 992.66 989.75 ± 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 Nitric acid HON(O)O (aq, 15 H2O) -205.70 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*817 Formic acid HC(O)OH (aq, 9 H2O) -425.19 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*814 Ethylene anion [CH2CH2]- (g) 232.1 225.6 ± 2.0 kJ/mol 28.0537 ± 0.0016 34527-91-8*0 Fluorosyl fluoride cation [FFO]+ (g) 1413.1 1413.4 ± 3.5 kJ/mol 53.99566 ± 0.00030 *86825-50-5*0 3H-diazirin-3-ylidene-methylene CC(NN) (g) 837.3 839.9 ± 2.3 kJ/mol 52.0349 ± 0.0016 204253-88-3*0 Peroxyformic acid HC(O)OOH (g) -279.25 -288.38 ± 0.63 kJ/mol 62.0248 ± 0.0012 107-32-4*0 Hydrogen bromide HBr (aq, 10000 H2O) -120.36 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*850 Sulfuric acid cation [OS(O)(OH)2]+ (g) 400.8 387.8 ± 3.2 kJ/mol 98.0789 ± 0.0061 247933-66-0*0 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 Cyanic acid cation [HOCN]+ (g) 1135.8 1133.2 ± 2.9 kJ/mol 43.02423 ± 0.00086 59780-31-3*0 Formic acid HC(O)OH (aq, 10 H2O) -425.19 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*815 Phosgene cation [CCl2O]+ (g) 897.0 896.0 ± 1.7 kJ/mol 98.9150 ± 0.0020 73249-38-4*0 Sulfate [OS(O)(O)O]-2 (aq) -909.16 ± 0.13 kJ/mol 96.0647 ± 0.0061 14808-79-8*800 Phosgene CCl2O (cr, l, I+liquid) -242.79 ± 0.25 kJ/mol 98.9155 ± 0.0020 75-44-5*501 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, 10 H2O) -880.42 ± 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 Formic acid HC(O)OH (aq, 12 H2O) -425.19 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*816 Phosgene CCl2O (cr, l, II+liquid) -255.49 -242.79 ± 0.25 kJ/mol 98.9155 ± 0.0020 75-44-5*502 Formic acid HC(O)OH (aq, 15 H2O) -425.19 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*817 Propene CH3CHCH2 (cr,l) 7.74 4.03 ± 0.82 kJ/mol 42.0797 ± 0.0024 115-07-1*500 Sulfuric acid OS(O)(OH)2 (aq, 150 H2O) -888.08 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*829 Sulfuric acid OS(O)(OH)2 (aq, 200 H2O) -888.52 ± 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 Peroxyformate [HC(O)OO]- (g) -340.95 -346.40 ± 0.80 kJ/mol 61.0174 ± 0.0012 104960-05-6*0 Chloro(chlorooxy)methylene ClCOCl (g) 73.5 73.9 ± 3.6 kJ/mol 98.9155 ± 0.0020 479587-31-0*0 Sulfuric acid OS(O)(OH)2 (aq, 900 H2O) -891.94 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*838 Chloro(chlorooxy)methylene ClCOCl (g, trans) 98. 105. ± 15. kJ/mol 98.9155 ± 0.0020 479587-31-0*1 Glycolaldehyde HC(O)CH2OH (g) -304.32 -317.36 ± 0.89 kJ/mol 60.0520 ± 0.0017 141-46-8*0 Cyclopropylidene C(CH2CH2) (g) 475.05 467.03 ± 0.84 kJ/mol 40.0639 ± 0.0024 2143-70-6*0 Sulfuric acid OS(O)(OH)2 (aq, 4000 H2O) -897.00 ± 0.13 kJ/mol 98.0795 ± 0.0061 7664-93-9*843 Hydrogen iodide HI (aq, 15 H2O) -54.588 ± 0.092 kJ/mol 127.912410 ± 0.000076 10034-85-2*817 Nitrosodioxaziridine ONN(OO) (g, cis) 413.9 408.1 ± 3.2 kJ/mol 76.01168 ± 0.00091 132871-99-9*2 Formic acid HC(O)OH (aq, 20 H2O) -425.19 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*818 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 Formic acid HC(O)OH (aq, 25 H2O) -425.20 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*819 C=O-C cation [COC]+ (g) 1585.8 1592.9 ± 2.7 kJ/mol 40.0203 ± 0.0016 83483-98-1*0 Chlorohydroxymethylene ClCOH (g, cis) 14.4 11.5 ± 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 Oxirane O(CH2CH2) (cr,l) -77.18 -77.85 ± 0.61 kJ/mol 44.0526 ± 0.0017 75-21-8*500 (Chlorooxy)methylene HCOCl (g, trans) 155.5 155.3 ± 3.7 kJ/mol 64.4707 ± 0.0012 331419-80-8*1 (Chlorooxy)methylene HCOCl (g) 119.2 117.9 ± 2.7 kJ/mol 64.4707 ± 0.0012 331419-80-8*0 Oxoiodonium [IO]+ (g) 1066.2 1064.2 ± 1.9 kJ/mol 142.90332 ± 0.00030 81182-81-2*0 Hydrogen chloride HCl (aq, 20 H2O) -163.675 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*818 Chloroformyl anion [ClCO]- (g) -356.5 -352.9 ± 3.3 kJ/mol 63.4633 ± 0.0012 41976-93-6*0 Hydroxyaminylium [HNOH]+ (g) 1019.5 1012.3 ± 2.5 kJ/mol 32.02147 ± 0.00034 66097-71-0*0 Hydrogen bromide HBr (aq, 2640 H2O) -120.24 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*957 Cyanogen iodide cation [ICN]+ (g) 1271.3 1271.2 ± 1.7 kJ/mol 152.92136 ± 0.00080 34749-78-5*0 Hydrogen iodide HI (aq, 20 H2O) -55.09 ± 0.12 kJ/mol 127.912410 ± 0.000076 10034-85-2*818 Difluorodinitrate [FNNF]- (g, trans) -207.8 -206.6 ± 4.7 kJ/mol 66.01083 ± 0.00014 37366-65-7*1 Diazomethylium [HCNN]+ (g) 1395.8 1394.1 ± 1.3 kJ/mol 41.03157 ± 0.00082 271249-81-1*0 Nitric acid HON(O)O (aq, 30 H2O) -206.03 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*820 Hydrogen iodide HI (aq, 7 H2O) -51.304 ± 0.099 kJ/mol 127.912410 ± 0.000076 10034-85-2*812 2-Iodoethanol ICH2CH2OH (g) -131.9 -150.1 ± 2.5 kJ/mol 171.9650 ± 0.0017 624-76-0*0 Trioxidaniumyl [HOOOH]+ (g) 925.5 916.6 ± 1.4 kJ/mol 50.01353 ± 0.00091 161321-37-5*0 Hydrogen bromide HBr (aq, 5 H2O) -110.68 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*809 Hydrogen iodide HI (aq, 10000 H2O) -56.693 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*850 1,3,5-Hexatriyne cation [HCCCCCCH]+ (g) 1600.9 1605.6 ± 2.8 kJ/mol 74.0795 ± 0.0048 61866-06-6*0 Hydrogen iodide HI (aq, 1500 H2O) -56.521 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*840 Methoxymethylene CH3OCH (g, singlet) 129.24 118.74 ± 0.78 kJ/mol 44.0526 ± 0.0017 19527-10-7*2 Propylidene anion [CH3CH2CH]- (g) 300.9 286.7 ± 3.2 kJ/mol 42.0803 ± 0.0024 *121408-55-7*0 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 Isocyanomethane CH3NC (cr,l) 146.4 ± 2.2 kJ/mol 41.0520 ± 0.0016 593-75-9*500 Hydrogen iodide HI (aq, 900 H2O) -56.450 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*838 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 O--HH Complex (H2)(O) (g, vdW C2v ?) 247.2 248.2 ± 2.0 kJ/mol 18.01528 ± 0.00033 *7732-18-5*102 Methoxymethylene CH3OCH (g) 129.24 118.74 ± 0.78 kJ/mol 44.0526 ± 0.0017 19527-10-7*0 Cyanic acid anion [HOCN]- (g) -9.2 -9.5 ± 3.1 kJ/mol 43.02533 ± 0.00086 58199-47-6*0 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) -612.76 ± 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) -616.74 ± 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) -620.09 ± 0.14 kJ/mol 82.0801 ± 0.0061 7782-99-2*847 Sulfurous acid S(O)(OH)2 (aq, 10000 H2O) -620.68 ± 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, 1000 H2O) -56.467 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*839 Trihydrogen cation [H3]+ (g, ortho) 1110.577 1106.695 ± 0.013 kJ/mol 3.02327 ± 0.00021 28132-48-1*1 Formic acid HC(O)OH (aq, 30 H2O) -425.20 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*820 Hydrogen fluoride HF (aq, 7500 H2O) -324.98 ± 0.16 kJ/mol 20.006343 ± 0.000070 7664-39-3*847 3,3-Dioxidedioxathiirane OS(OO)O (g) -257.1 -265.2 ± 1.4 kJ/mol 96.0636 ± 0.0061 1177730-84-5*0 Nitric acid HON(O)O (aq, 20 H2O) -205.92 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*818 Hydrogen bromide HBr (aq, 3 H2O) -102.21 ± 0.13 kJ/mol 80.9119 ± 0.0010 10035-10-6*805 Sulfur tetraoxide OS(O)(O)O (g) -228.2 -235.0 ± 2.0 kJ/mol 96.0636 ± 0.0061 12772-98-4*0 Formic acid HC(O)OH (aq, 40 H2O) -425.22 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*821 Sulfur tetraoxide OS(O)(O)O (g, triplet) -228.2 -235.0 ± 2.0 kJ/mol 96.0636 ± 0.0061 12772-98-4*1 Sulfur tetraoxide OS(O)(O)O (g, singlet) -163.7 -169.4 ± 2.9 kJ/mol 96.0636 ± 0.0061 12772-98-4*2 Formic acid HC(O)OH (aq, 50 H2O) -425.24 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*822 Fluorosyl fluoride anion [FFO]- (g) -147.1 -146.8 ± 3.0 kJ/mol 53.99675 ± 0.00030 *86825-57-2*0 Sulfur tetraoxide OS(O)(O)O (g, singlet C3v ?) -155.5 -164.3 ± 4.0 kJ/mol 96.0636 ± 0.0061 12772-98-4*23 Dichlorine cation [Cl2]+ (g) 1108.307 1108.286 ± 0.0062 kJ/mol 70.9049 ± 0.0018 12595-90-3*0 Difluoroaminylium [NF2]+ (g) 1157.82 1154.93 ± 0.71 kJ/mol 52.002998 ± 0.000070 31685-31-1*0 Hydrogen iodide HI (aq, 25 H2O) -55.35 ± 0.11 kJ/mol 127.912410 ± 0.000076 10034-85-2*819 Formic acid HC(O)OH (aq, 55.51 H2O) -425.25 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*891 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, 25 H2O) -206.00 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*819 5-Ethenyl-1,3-cyclopentadiene CH2CHCH(CHCHCHCH) (g) 237.0 216.2 ± 1.4 kJ/mol 92.1384 ± 0.0056 29647-85-6*0 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 Formic acid HC(O)OH (aq, 75 H2O) -425.27 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*825 Methanethiol cation [CH3SH]+ (g) 901.89 891.85 ± 0.46 kJ/mol 48.1079 ± 0.0061 53369-41-8*0 Formic acid HC(O)OH (aq, 111 H2O) -425.30 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*892 Formic acid HC(O)OH (aq, 200 H2O) -425.33 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*830 Methanediimine cation [HNCNH]+ (g) 1137.8 1135.7 ± 2.2 kJ/mol 42.03951 ± 0.00082 1189338-16-6*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 mu-Oxodioxodinitrogen [ONONO]+ (g, t, t) 984.0 981.0 ± 3.2 kJ/mol 76.01113 ± 0.00091 87950-63-8*1 Ethanethiol cation [CH3CH2SH]+ (g) 867.11 850.95 ± 0.59 kJ/mol 62.1345 ± 0.0062 69762-64-7*0 Dioxohydrazine ONNO (g, trans) 192.3 188.7 ± 1.8 kJ/mol 60.01228 ± 0.00062 16824-89-8*1 Chlorine atom heptacation [Cl]+7 (g) 39520. 39522. ± 11. kJ/mol 35.44886 ± 0.00090 22537-27-5*0 Dimethyl sulfide cation [CH3SCH3]+ (g) 817.86 802.11 ± 0.48 kJ/mol 62.1345 ± 0.0062 34480-65-4*0 Diatomic bromine cation [Br2]+ (g) 1060.34 1045.39 ± 0.23 kJ/mol 159.8075 ± 0.0020 12595-71-0*0 Hydrogen chloride HCl (aq, 100000 H2O) -166.947 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*861 5-Ethenyl-1,3-cyclopentadiene CH2CHCH(CHCHCHCH) (g, gauche) 242.0 220.1 ± 2.2 kJ/mol 92.1384 ± 0.0056 29647-85-6*2 Ethylidene CH3CH (g) 361.30 354.32 ± 0.48 kJ/mol 28.0532 ± 0.0016 4218-50-2*0 Hydrogen cyanide anion [HCN]- (g) 129.536 129.058 ± 0.087 kJ/mol 27.02593 ± 0.00081 12334-27-9*0 Formic acid HC(O)OH (aq, 300 H2O) -425.33 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*831 Nitric acid HON(O)O (aq, 10000 H2O) -206.42 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*850 Carbon disulfide cation [SCS]+ (g) 1088.29 1090.04 ± 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 Formic acid HC(O)OH (aq, 400 H2O) -425.34 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*832 2-Hydroxyethylium [CH2CH2OH]+ (g) 1019.3 1007.2 ± 1.5 kJ/mol 45.0600 ± 0.0017 38607-31-7*0 Carbon monosulfide cation [CS]+ (g) 1371.34 1374.58 ± 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 Methanediimine cation [HNCNH]+ (g, trans) 1139.1 1136.2 ± 3.2 kJ/mol 42.03951 ± 0.00082 1189338-16-6*1 Platinum atom anion Pt- (g) 358.4 358.9 ± 1.7 kJ/mol 195.0785 ± 0.0020 40817-31-0*0 Hydrogen bromide HBr (aq, 100000 H2O) -120.44 ± 0.12 kJ/mol 80.9119 ± 0.0010 10035-10-6*861 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 Hydrogen iodide HI (aq, 5 H2O) -47.73 ± 0.32 kJ/mol 127.912410 ± 0.000076 10034-85-2*809 Cycloprop-2-yliumyl [CH2(CHCH)]+ (g) 1225.54 1218.39 ± 0.58 kJ/mol 40.0633 ± 0.0024 65812-78-4*0 Hydrogen fluoride HF (aq, 250 H2O) -322.12 ± 0.10 kJ/mol 20.006343 ± 0.000070 7664-39-3*908 Hydrogen atom H (ad, Pt(111) fcc) -37.0 -40.2 ± 1.1 kJ/mol 1.007940 ± 0.000070 12385-13-6*1001000 Formic acid HC(O)OH (aq, 500 H2O) -425.34 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*833 Hydroxyformyl HOCO (g) -181.15 -183.70 ± 0.40 kJ/mol 45.0174 ± 0.0010 2564-86-5*0 Cyanoamidogen HNCN (g) 322.71 320.23 ± 0.63 kJ/mol 41.03212 ± 0.00082 12347-01-2*0 Peroxyformyl HC(O)OO (g) -100.42 -105.53 ± 0.67 kJ/mol 61.0168 ± 0.0012 56240-83-6*0 Hydrogen atom H (ad, Pt(111) atop) -32. -34. ± 20. kJ/mol 1.007940 ± 0.000070 12385-13-6*1002000 Nitric acid HON(O)O (aq, 50000 H2O) -206.49 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*855 Formic acid HC(O)OH (aq, 555.1 H2O) -425.34 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*895 Formic acid HC(O)OH (aq, 600 H2O) -425.35 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*834 Hydrogen fluoride HF (aq, 37 H2O) -321.91 ± 0.11 kJ/mol 20.006343 ± 0.000070 7664-39-3*890 Formic acid HC(O)OH (aq, 700 H2O) -425.35 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*835 Formic acid HC(O)OH (aq, 800 H2O) -425.35 ± 0.60 kJ/mol 46.0254 ± 0.0010 64-18-6*837 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 Dinitrogen N2 (aq, undissoc) -10.30 ± 0.32 kJ/mol 28.01348 ± 0.00014 7727-37-9*1000 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) -0.69 ± 0.16 kJ/mol 4.0026020 ± 0.0000020 7440-59-7*1000 Dichlorine Cl2 (aq, undissoc) -16.54 ± 0.12 kJ/mol 70.9054 ± 0.0018 7782-50-5*1000 Dihydrogen H2 (aq, undissoc) -4.099 ± 0.080 kJ/mol 2.01588 ± 0.00014 1333-74-0*1000 Neon Ne (aq, undissoc) -3.87 ± 0.16 kJ/mol 20.17970 ± 0.00060 7440-01-9*1000 Dioxygen O2 (aq, undissoc) -11.961 ± 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) -12.24 ± 0.16 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) -15.63 ± 0.16 kJ/mol 83.8000 ± 0.1000 7439-90-9*1000 Xenon Xe (aq, undissoc) -19.39 ± 0.64 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. 1.156 of the Thermochemical Network (2024); available at ATcT.anl.gov
4
N. A. Seifert, B. Ruscic, R. Sivaramakrishnan, and K. Prozument,
The C2H4O Isomers in the Oxidation of Ethylene
J. Mol. Spectrosc. 398 , 111847/1-8 (2023)
[DOI: 10.1016/j.jms.2023.111847]
5
U. Jacovella, B. Ruscic, N. L. Chen, H.-L. Le, S. Boyé-Péronne, S. Hartweg, M. Roy-Chowdhury, G. A. Garcia, J.-C. Loison, and B. Gans,
Refining Thermochemical Properties of CF, SiF, and Their Cations by Combining Photoelectron Spectroscopy, Quantum Chemical Calculations, and the Active Thermochemical Tables Approach
Phys. Chem. Chem. Phys. 25 , 30838-30847 (2023)
[DOI: 10.1039/D3CP04244H]
6
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]
7
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 [6 ] and Ruscic and Bross[7 ]).
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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