ATcT [1 , 2 ] enthalpies of formation based on version 1.122p of the Thermochemical Network [3 ]
Below is a list of 0 K and 298.15 K enthalpies of formation
for all 1727 species included in version 1.122p. This version of ATcT results was generated from an expansion of version 1.122o [4 ] to include an updated enthalpy of formation for Hydrazine . [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.)
If you find Active Thermochemical Tables useful in your research, please cite this website as given in Ref. [3 ], and, if possible, the ATcT approach as given in Refs. [1 ] and [2 ].
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 atom 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 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 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 atom C (g) 711.397 716.882 ± 0.047 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 Nitrogen atom N (g) 470.579 472.441 ± 0.024 kJ/mol 14.006740 ± 0.000070 17778-88-0*0 Carbon dioxide CO2 (g) -393.108 -393.474 ± 0.015 kJ/mol 44.00950 ± 0.00100 124-38-9*0 Chlorine atom Cl (g) 119.621 121.302 ± 0.0011 kJ/mol 35.45270 ± 0.00090 22537-15-1*0 Methane CH4 (g) -66.561 -74.530 ± 0.055 kJ/mol 16.04246 ± 0.00085 74-82-8*0 Fluorine atom F (g) 77.258 79.364 ± 0.048 kJ/mol 18.99840320 ± 0.00000050 14762-94-8*0 Ethane CH3CH3 (g) -68.36 -83.98 ± 0.13 kJ/mol 30.0690 ± 0.0017 74-84-0*0 Water H2O (cr,l) -286.302 -285.830 ± 0.026 kJ/mol 18.01528 ± 0.00033 7732-18-5*500 Water H2O (g) -238.933 -241.836 ± 0.026 kJ/mol 18.01528 ± 0.00033 7732-18-5*0 Hydron H+ (g) 1528.084 1530.047 ± 0.000 kJ/mol 1.007391 ± 0.000070 12408-02-5*0 Ethylene CH2CH2 (g) 60.87 52.35 ± 0.12 kJ/mol 28.0532 ± 0.0016 74-85-1*0 Bromine atom Br (g) 117.914 111.851 ± 0.056 kJ/mol 79.90400 ± 0.00100 10097-32-2*0 Methanol CH3OH (g) -190.04 -200.92 ± 0.15 kJ/mol 32.04186 ± 0.00090 67-56-1*0 Methyl CH3 (g) 149.867 146.453 ± 0.059 kJ/mol 15.03452 ± 0.00083 2229-07-4*0 Hydrogen chloride HCl (g) -91.989 -92.173 ± 0.0062 kJ/mol 36.46064 ± 0.00090 7647-01-0*0 Carbon monoxide CO (g) -113.803 -110.523 ± 0.026 kJ/mol 28.01010 ± 0.00085 630-08-0*0 Hydroxyl OH (g) 37.248 37.488 ± 0.026 kJ/mol 17.00734 ± 0.00031 3352-57-6*0 Formaldehyde CH2O (g) -105.377 -109.215 ± 0.097 kJ/mol 30.02598 ± 0.00087 50-00-0*0 Propane CH3CH2CH3 (g) -82.76 -105.04 ± 0.18 kJ/mol 44.0956 ± 0.0025 74-98-6*0 Hydrogen fluoride HF (g) -272.674 -272.721 ± 0.049 kJ/mol 20.006343 ± 0.000070 7664-39-3*0 Ethanol CH3CH2OH (g) -217.31 -235.03 ± 0.22 kJ/mol 46.0684 ± 0.0017 64-17-5*0 Hydrogen bromide HBr (g) -27.94 -35.79 ± 0.14 kJ/mol 80.9119 ± 0.0010 10035-10-6*0 Iodine I (g) 107.157 106.757 ± 0.0021 kJ/mol 126.904470 ± 0.000030 14362-44-8*0 Acetylene HCCH (g) 228.82 228.26 ± 0.13 kJ/mol 26.0373 ± 0.0016 74-86-2*0 Ethyl CH3CH2 (g) 131.04 119.98 ± 0.27 kJ/mol 29.0611 ± 0.0016 2025-56-1*0 Hydrogen cyanide HCN (g) 129.663 129.278 ± 0.090 kJ/mol 27.02538 ± 0.00081 74-90-8*0 Nitric oxide NO (g) 90.617 91.121 ± 0.065 kJ/mol 30.00614 ± 0.00031 10102-43-9*0 Chloromethane CH3Cl (g) -74.63 -82.56 ± 0.19 kJ/mol 50.4872 ± 0.0012 74-87-3*0 Ammonia NH3 (g) -38.564 -45.557 ± 0.029 kJ/mol 17.03056 ± 0.00022 7664-41-7*0 Propene CH3CHCH2 (g) 34.92 19.92 ± 0.21 kJ/mol 42.0797 ± 0.0024 115-07-1*0 Nitrogen dioxide ONO (g) 36.856 34.049 ± 0.065 kJ/mol 46.00554 ± 0.00060 10102-44-0*0 Hydrogen iodide HI (g) 28.645 26.470 ± 0.036 kJ/mol 127.912410 ± 0.000076 10034-85-2*0 Hydroxyde [OH]- (g) -139.093 -139.060 ± 0.026 kJ/mol 17.00789 ± 0.00031 14280-30-9*0 Benzene C6H6 (g) 100.61 83.10 ± 0.23 kJ/mol 78.1118 ± 0.0048 71-43-2*0 Acetaldehyde CH3CHO (g) -155.12 -165.60 ± 0.26 kJ/mol 44.0526 ± 0.0017 75-07-0*0 Dioxidanyl HO2 (g) 15.12 12.22 ± 0.15 kJ/mol 33.00674 ± 0.00060 3170-83-0*0 Fluoromethane CH3F (g) -227.46 -235.49 ± 0.23 kJ/mol 34.03292 ± 0.00083 593-53-3*0 Hydrogen peroxide H2O2 (g) -129.480 -135.466 ± 0.063 kJ/mol 34.01468 ± 0.00062 7722-84-1*0 Bromomethane CH3Br (g) -20.86 -36.26 ± 0.18 kJ/mol 94.9385 ± 0.0013 74-83-9*0 n-Butane CH3CH2CH2CH3 (g) -98.47 -125.78 ± 0.25 kJ/mol 58.1222 ± 0.0033 106-97-8*0 Methylene CH2 (g, triplet) 391.061 391.618 ± 0.097 kJ/mol 14.02658 ± 0.00081 2465-56-7*1 Methylene CH2 (g, singlet) 428.72 429.13 ± 0.11 kJ/mol 14.02658 ± 0.00081 2465-56-7*2 Hypochlorous acid HOCl (g) -73.870 -76.809 ± 0.027 kJ/mol 52.46004 ± 0.00095 7790-92-3*0 Propyne CH3CCH (g) 192.77 185.71 ± 0.24 kJ/mol 40.0639 ± 0.0024 74-99-7*0 Formic acid HC(O)OH (g, syn) -371.11 -378.42 ± 0.22 kJ/mol 46.0254 ± 0.0010 64-18-6*1 Dibromine Br2 (g) 45.68 30.88 ± 0.11 kJ/mol 159.8080 ± 0.0020 7726-95-6*0 Tetrachloromethane CCl4 (g) -93.41 -95.58 ± 0.43 kJ/mol 153.8215 ± 0.0037 56-23-5*0 Methylamine CH3NH2 (g) -6.67 -21.38 ± 0.27 kJ/mol 31.05714 ± 0.00088 74-89-5*0 Fluoride F- (g) -250.907 -249.122 ± 0.048 kJ/mol 18.99895178 ± 0.00000050 16984-48-8*0 Ketene CH2CO (g) -45.35 -48.47 ± 0.12 kJ/mol 42.0367 ± 0.0016 463-51-4*0 Tetrafluoromethane CF4 (g) -927.50 -933.47 ± 0.25 kJ/mol 88.00431 ± 0.00080 75-73-0*0 Chloroethane CH3CH2Cl (g) -96.90 -111.49 ± 0.26 kJ/mol 64.5138 ± 0.0019 75-00-3*0 Vinyl CH2CH (g) 301.16 296.96 ± 0.33 kJ/mol 27.0452 ± 0.0016 2669-89-8*0 Acetone CH3C(O)CH3 (g) -200.08 -216.77 ± 0.36 kJ/mol 58.0791 ± 0.0025 67-64-1*0 Methylidyne CH (g) 592.820 596.154 ± 0.099 kJ/mol 13.01864 ± 0.00080 3315-37-5*0 Methoxide [CH3O]- (g) -122.64 -130.37 ± 0.30 kJ/mol 31.03447 ± 0.00088 3315-60-4*0 Acetonitrile CH3CN (g) 81.09 74.04 ± 0.25 kJ/mol 41.0520 ± 0.0016 75-05-8*0 Oxonium [H3O]+ (g) 605.84 599.09 ± 0.17 kJ/mol 19.02267 ± 0.00037 13968-08-6*0 Ozone OOO (g) 144.397 141.735 ± 0.039 kJ/mol 47.99820 ± 0.00090 10028-15-6*0 Diiodine I2 (g) 65.497 62.417 ± 0.0041 kJ/mol 253.808940 ± 0.000060 7553-56-2*0 Phenyl C6H5 (g) 350.35 336.99 ± 0.53 kJ/mol 77.1039 ± 0.0048 2396-01-2*0 Toluene C6H5CH3 (g) 73.29 50.01 ± 0.34 kJ/mol 92.1384 ± 0.0056 108-88-3*0 Fluoroform CHF3 (g) -689.03 -695.98 ± 0.41 kJ/mol 70.01385 ± 0.00080 75-46-7*0 Trifluoromethyl CF3 (g) -464.96 -467.76 ± 0.48 kJ/mol 69.00591 ± 0.00080 2264-21-3*0 Ethylium [CH3CH2]+ (g) 914.84 902.76 ± 0.31 kJ/mol 29.0606 ± 0.0016 14936-94-8*0 Nitrilomethyl CN (g) 436.75 440.04 ± 0.14 kJ/mol 26.01744 ± 0.00080 2074-87-5*0 1,3-Butadiene CH2CHCHCH2 (g) 125.30 110.82 ± 0.36 kJ/mol 54.0904 ± 0.0032 106-99-0*0 Phenol C6H5OH (g) -74.66 -93.26 ± 0.64 kJ/mol 94.1112 ± 0.0048 108-95-2*0 Chloride Cl- (g) -228.953 -227.346 ± 0.0021 kJ/mol 35.45325 ± 0.00090 16887-00-6*0 Bromide Br- (g) -206.623 -212.685 ± 0.056 kJ/mol 79.90455 ± 0.00100 24959-67-9*0 Hypobromous acid HOBr (g) -51.61 -62.08 ± 0.47 kJ/mol 96.9113 ± 0.0010 13517-11-8*0 Methoxy CH3O (g) 28.82 21.45 ± 0.29 kJ/mol 31.03392 ± 0.00088 2143-68-2*0 Formyl HCO (g) 41.393 41.770 ± 0.097 kJ/mol 29.01804 ± 0.00086 2597-44-6*0 Acetic acid CH3C(O)OH (g, syn) -418.86 -432.98 ± 0.43 kJ/mol 60.0520 ± 0.0017 64-19-7*1 Hydroxymethyl CH2OH (g) -10.44 -16.75 ± 0.28 kJ/mol 31.03392 ± 0.00088 2597-43-5*0 Chlorooxidanyl ClO (g) 101.125 101.716 ± 0.035 kJ/mol 51.45210 ± 0.00095 14989-30-1*0 Oxomethylium [HCO]+ (g) 827.769 827.184 ± 0.097 kJ/mol 29.01749 ± 0.00086 17030-74-9*0 Allene CH2CCH2 (g) 197.32 189.83 ± 0.25 kJ/mol 40.0639 ± 0.0024 463-49-0*0 Imidogen NH (g) 358.74 358.78 ± 0.17 kJ/mol 15.014680 ± 0.000099 13774-92-0*0 Dioxymethyl CH2OO (g) 111.89 104.89 ± 0.63 kJ/mol 46.0254 ± 0.0010 56077-92-0*0 Difluorophosgene CF2O (g) -603.35 -606.45 ± 0.41 kJ/mol 66.00691 ± 0.00085 353-50-4*0 Nitric acid HON(O)O (g) -124.50 -134.21 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*0 Amidogen NH2 (g) 188.91 186.02 ± 0.11 kJ/mol 16.02262 ± 0.00016 13770-40-6*0 Allyl CH2CHCH2 (g) 180.03 168.30 ± 0.45 kJ/mol 41.0718 ± 0.0024 1981-80-2*0 Iodide I- (g) -187.995 -188.396 ± 0.0021 kJ/mol 126.905019 ± 0.000030 20461-54-5*0 Cyanogen chloride ClCN (g) 134.95 135.65 ± 0.46 kJ/mol 61.4701 ± 0.0012 506-77-4*0 iso-Butane CH(CH3)3 (g) -106.03 -134.64 ± 0.31 kJ/mol 58.1222 ± 0.0033 75-28-5*0 Isocyanic acid HNCO (g) -116.01 -119.00 ± 0.30 kJ/mol 43.02478 ± 0.00086 75-13-8*0 Methylium [CH3]+ (g) 1099.336 1095.392 ± 0.056 kJ/mol 15.03397 ± 0.00083 14531-53-4*0 Hypofluorous acid HOF (g) -84.39 -87.29 ± 0.19 kJ/mol 36.00574 ± 0.00031 14034-79-8*0 Hydrogen chloride HCl (aq, 600 H2O) -166.452 ± 0.024 kJ/mol 36.46064 ± 0.00090 7647-01-0*834 Ethoxide [CH3CH2O]- (g) -163.83 -178.77 ± 0.47 kJ/mol 45.0610 ± 0.0017 16331-64-9*0 Propargyl CH2CCH (g) 353.96 351.37 ± 0.37 kJ/mol 39.0559 ± 0.0024 2932-78-7*0 Dichloromethane CH2Cl2 (g) -86.70 -93.56 ± 0.52 kJ/mol 84.9320 ± 0.0020 75-09-2*0 Vinyl chloride CH2CHCl (g) 29.26 21.68 ± 0.30 kJ/mol 62.4979 ± 0.0018 75-01-4*0 Chlorobenzene C6H5Cl (g) 67.14 52.18 ± 0.61 kJ/mol 112.5566 ± 0.0049 108-90-7*0 Cyanogen bromide BrCN (g) 186.7 180.1 ± 1.1 kJ/mol 105.9214 ± 0.0013 506-68-3*0 Iodomethane CH3I (g) 24.50 14.97 ± 0.18 kJ/mol 141.93899 ± 0.00083 74-88-4*0 Hydroxyformyl HOCO (g, trans) -181.09 -184.06 ± 0.46 kJ/mol 45.0174 ± 0.0010 2564-86-5*1 Oxygen atom anion O- (g) 105.868 108.097 ± 0.0021 kJ/mol 15.99995 ± 0.00030 14337-01-0*0 Trihydrogen cation [H3]+ (g) 1110.304 1106.696 ± 0.013 kJ/mol 3.02327 ± 0.00021 28132-48-1*0 Methyl hydroperoxide CH3OOH (g) -114.94 -127.76 ± 0.70 kJ/mol 48.0413 ± 0.0010 3031-73-0*0 Methylperoxy CH3OO (g) 22.30 12.66 ± 0.47 kJ/mol 47.0333 ± 0.0010 2143-58-0*0 n-Propyl CH3CH2CH2 (g) 118.30 100.90 ± 0.55 kJ/mol 43.0877 ± 0.0024 2143-61-5*0 iso-Propyl CH3CHCH3 (g) 105.31 88.44 ± 0.53 kJ/mol 43.0877 ± 0.0024 2025-55-0*0 2-Hydroxyethyl CH2CH2OH (g, gauche-syn) -13.34 -26.60 ± 0.56 kJ/mol 45.0605 ± 0.0017 4422-54-2*1 Tetrabromomethane CBr4 (g) 132.9 103.2 ± 1.3 kJ/mol 331.6267 ± 0.0041 558-13-4*0 Difluoromethane CH2F2 (g) -443.08 -450.70 ± 0.33 kJ/mol 52.02339 ± 0.00081 75-10-5*0 Cyanoacetylene HCCCN (g) 371.94 373.68 ± 0.67 kJ/mol 51.0468 ± 0.0024 1070-71-9*0 Oxygen difluoride FOF (g) 26.81 24.56 ± 0.24 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 Isocyanomethane CH3NC (g) 183.18 176.71 ± 0.67 kJ/mol 41.0520 ± 0.0016 593-75-9*0 Propynylidene HCCCH (g, triplet) 543.41 546.40 ± 0.64 kJ/mol 38.0480 ± 0.0024 67152-18-5*1 Ethenol CH2CHOH (g, syn) -112.77 -123.97 ± 0.66 kJ/mol 44.0526 ± 0.0017 557-75-5*1 Chloroform CHCl3 (g) -97.29 -102.19 ± 0.50 kJ/mol 119.3767 ± 0.0028 67-66-3*0 Fluoromethylidyne CF (g) 243.14 246.74 ± 0.13 kJ/mol 31.00910 ± 0.00080 3889-75-6*0 Acrylonitrile CH2CHCN (g, singlet) 193.84 187.08 ± 0.71 kJ/mol 53.0627 ± 0.0024 107-13-1*1 Oxygen atom cation O+ (g) 1560.786 1562.644 ± 0.0021 kJ/mol 15.99885 ± 0.00030 14581-93-2*0 1,2-Propadiene-1,3-diylidene CCC (g) 814.66 823.62 ± 0.55 kJ/mol 36.0321 ± 0.0024 12075-35-3*0 Cyanic fluoride FCN (g) 8.78 9.11 ± 0.69 kJ/mol 45.01584 ± 0.00080 1495-50-7*0 1-Hydroxyethyl CH3CHOH (g, gauche-anti) -42.74 -56.17 ± 0.58 kJ/mol 45.0605 ± 0.0017 2348-46-1*1 Acetyl CH3CO (g) -3.35 -10.01 ± 0.34 kJ/mol 43.0446 ± 0.0016 3170-69-2*0 Formate [HC(O)O]- (g) -463.20 -466.85 ± 0.56 kJ/mol 45.0180 ± 0.0010 71-47-6*0 Methyl formate HC(O)OCH3 (g, syn) -346.86 -359.91 ± 0.84 kJ/mol 60.0520 ± 0.0017 107-31-3*1 Tetrafluoroethylene CF2CF2 (g) -671.03 -674.43 ± 0.54 kJ/mol 100.0150 ± 0.0016 116-14-3*0 Ethyl bromide CH3CH2Br (g) -41.38 -63.33 ± 0.25 kJ/mol 108.9651 ± 0.0019 74-96-4*0 Vinyl bromide CH2CHBr (g) 88.57 73.76 ± 0.58 kJ/mol 106.9492 ± 0.0019 593-60-2*0 Chlorine fluoride ClF (g) -55.617 -55.712 ± 0.055 kJ/mol 54.45110 ± 0.00090 7790-89-8*0 Hydride H- (g) 143.264 145.228 ± 0.000 kJ/mol 1.008489 ± 0.000070 12184-88-2*0 Diazynium [NNH]+ (g) 1042.43 1038.82 ± 0.68 kJ/mol 29.02087 ± 0.00016 12357-66-3*0 Nitrite [ONO]- (g) -182.63 -185.44 ± 0.46 kJ/mol 46.00609 ± 0.00060 14797-65-0*0 Hydroxylamine NH2OH (g, trans) -33.23 -43.61 ± 0.46 kJ/mol 33.02996 ± 0.00037 7803-49-8*1 Nitrosyl hydride HNO (g) 109.93 106.96 ± 0.11 kJ/mol 31.01408 ± 0.00032 14332-28-6*0 Nitrous acid HONO (g, trans) -73.008 -79.152 ± 0.078 kJ/mol 47.01348 ± 0.00061 7782-77-6*1 Ethynylene C2 (g) 820.28 828.75 ± 0.26 kJ/mol 24.0214 ± 0.0016 12070-15-4*0 Methanimine CH2NH (g) 96.48 88.57 ± 0.42 kJ/mol 29.04126 ± 0.00083 2053-29-4*0 n-Butyl CH3CH2CH2CH2 (g) 102.73 80.22 ± 0.70 kJ/mol 57.1143 ± 0.0033 2492-36-6*0 Cyclopentadiene CH2(CHCHCHCH) (g) 151.07 133.95 ± 0.66 kJ/mol 66.1011 ± 0.0040 542-92-7*0 Methoxymethane CH3OCH3 (g) -166.46 -183.96 ± 0.40 kJ/mol 46.0684 ± 0.0017 115-10-6*0 Methyl acetate CH3C(O)OCH3 (g, syn) -394.29 -413.15 ± 0.61 kJ/mol 74.0785 ± 0.0025 79-20-9*1 Phosgene CCl2O (g) -217.45 -219.14 ± 0.27 kJ/mol 98.9155 ± 0.0020 75-44-5*0 Chlorotrifluoromethane CF3Cl (g) -704.50 -709.61 ± 0.59 kJ/mol 104.4586 ± 0.0012 75-72-9*0 Vinyl fluoride CH2CHF (g) -134.56 -142.37 ± 0.45 kJ/mol 46.0436 ± 0.0016 75-02-5*0 Phenylium [C6H5]+ (g) 1148.39 1135.61 ± 0.85 kJ/mol 77.1034 ± 0.0048 17333-73-2*0 Formamide CH(O)NH2 (g) -178.52 -188.79 ± 0.38 kJ/mol 45.04066 ± 0.00088 75-12-7*0 Fluorooxidanyl FO (g) 110.27 110.89 ± 0.15 kJ/mol 34.99780 ± 0.00030 12061-70-0*0 Hypoiodous acid HOI (g) -54.2 -58.9 ± 3.1 kJ/mol 143.91181 ± 0.00031 14332-21-9*0 Methanium [CH5]+ (g) 921.92 911.67 ± 0.45 kJ/mol 17.04985 ± 0.00087 15135-49-6*0 Oxirane O(CH2CH2) (g) -40.07 -52.61 ± 0.37 kJ/mol 44.0526 ± 0.0017 75-21-8*0 Ethynyl CCH (g) 563.87 567.98 ± 0.14 kJ/mol 25.0293 ± 0.0016 2122-48-7*0 cis-2-Butene CH3CHCHCH3 (g, cis) 14.19 -7.08 ± 0.41 kJ/mol 56.1063 ± 0.0032 590-18-1*0 Ethynide [CCH]- (g) 277.41 280.82 ± 0.18 kJ/mol 25.0299 ± 0.0016 29075-95-4*0 Formic acid HC(O)OH (g, anti) -354.76 -361.86 ± 0.38 kJ/mol 46.0254 ± 0.0010 64-18-6*2 Methanetetraylbisamidogen NCN (g) 450.42 450.83 ± 0.64 kJ/mol 40.02418 ± 0.00081 2669-76-3*0 Fluoroethane CH3CH2F (g) -257.21 -272.07 ± 0.36 kJ/mol 48.0595 ± 0.0016 353-36-6*0 Bromotrifluoromethane CF3Br (g) -638.92 -651.04 ± 0.45 kJ/mol 148.9099 ± 0.0013 75-63-8*0 Phenide [C6H5]- (g) 244.32 230.90 ± 0.39 kJ/mol 77.1044 ± 0.0048 30922-78-2*0 Fluorobenzene C6H5F (g) -99.09 -114.76 ± 0.89 kJ/mol 96.1023 ± 0.0048 462-06-6*0 Nitromethane CH3N(O)O (g) -60.84 -74.74 ± 0.46 kJ/mol 61.0401 ± 0.0010 75-52-5*0 Chlorine dioxide OClO (g) 101.33 98.86 ± 0.27 kJ/mol 67.4515 ± 0.0011 10049-04-4*0 Dioxygen cation [O2]+ (g) 1164.585 1165.221 ± 0.0092 kJ/mol 31.99825 ± 0.00060 12185-07-8*0 Methylidyne CH (g, quartet) 664.55 667.88 ± 0.59 kJ/mol 13.01864 ± 0.00080 3315-37-5*2 Ethanide [CH3CH2]- (g) 155.28 144.20 ± 0.89 kJ/mol 29.0616 ± 0.0016 25013-41-6*0 Aminomethyl CH2NH2 (g) 159.16 149.32 ± 0.42 kJ/mol 30.04920 ± 0.00085 10507-29-6*0 Peroxyformic acid HC(O)OOH (g, cis) -279.27 -288.62 ± 0.90 kJ/mol 62.0248 ± 0.0012 107-32-4*1 Cyclopropane CH2(CH2CH2) (g) 70.97 53.84 ± 0.41 kJ/mol 42.0797 ± 0.0024 75-19-4*0 Propadienylidene CH2CC (g) 554.41 555.55 ± 0.41 kJ/mol 38.0480 ± 0.0024 60731-10-4*0 Ethoxy CH3CH2O (g, X 2A") 1.30 -12.61 ± 0.47 kJ/mol 45.0605 ± 0.0017 2154-50-9*51 Cyanooxidanyl NCO (g) 126.89 127.37 ± 0.34 kJ/mol 42.01684 ± 0.00086 22400-26-6*0 Phenolate [C6H5O]- (g) -146.37 -161.84 ± 0.88 kJ/mol 93.1038 ± 0.0048 3229-70-7*0 Dimethylamine (CH3)2NH (g) 3.75 -17.89 ± 0.47 kJ/mol 45.0837 ± 0.0017 124-40-3*0 Cyclopentadienyl CH(CHCHCHCH) (g) 274.50 261.39 ± 0.93 kJ/mol 65.0932 ± 0.0040 2143-53-5*0 Acrylonitrile CH2CHCN (g) 193.84 187.08 ± 0.71 kJ/mol 53.0627 ± 0.0024 107-13-1*0 Bromooxidanyl BrO (g) 131.14 123.61 ± 0.28 kJ/mol 95.9034 ± 0.0010 15656-19-6*0 Hypobromite [BrO]- (g) -96.14 -103.63 ± 0.53 kJ/mol 95.9039 ± 0.0010 14380-62-2*0 Hydrogen fluoride HF (aq) -334.50 ± 0.16 kJ/mol 20.006343 ± 0.000070 7664-39-3*800 Ammonium [NH4]+ (g) 643.02 631.71 ± 0.21 kJ/mol 18.03795 ± 0.00029 14798-03-9*0 Peroxynitrous acid HOONO (g, cis, cis) -5.81 -14.25 ± 0.36 kJ/mol 63.01288 ± 0.00091 14691-52-2*3 Ethylidene CH3CH (g, singlet) 373.61 366.38 ± 0.77 kJ/mol 28.0532 ± 0.0016 4218-50-2*2 Cyanogen NCCN (g) 308.16 310.10 ± 0.42 kJ/mol 52.0349 ± 0.0016 460-19-5*0 Cyanide [CN]- (g) 63.959 67.245 ± 0.094 kJ/mol 26.01799 ± 0.00080 57-12-5*0 Isobutene CH2C(CH3)2 (g) 4.02 -17.04 ± 0.42 kJ/mol 56.1063 ± 0.0032 115-11-7*0 1-Butene CH2CHCH2CH3 (g) 21.00 0.05 ± 0.38 kJ/mol 56.1063 ± 0.0032 106-98-9*0 n-Pentane CH3CH2CH2CH2CH3 (g) -114.40 -146.28 ± 0.31 kJ/mol 72.1488 ± 0.0041 109-66-0*0 Fluorodioxidanyl FOO (g) 26.81 25.10 ± 0.26 kJ/mol 50.99720 ± 0.00060 15499-23-7*0 Dichloromethylene CCl2 (g, singlet) 229.51 230.69 ± 0.64 kJ/mol 82.9161 ± 0.0020 1605-72-7*2 Difluorodioxidane FOOF (g) 35.27 31.55 ± 0.41 kJ/mol 69.99561 ± 0.00060 7783-44-0*0 Nitrous oxide NNO (g) 85.996 82.567 ± 0.097 kJ/mol 44.01288 ± 0.00033 10024-97-2*0 (E)-Diazene HNNH (g, trans) 207.09 199.95 ± 0.44 kJ/mol 30.02936 ± 0.00020 15626-43-4*0 Hydroxyoxomethylium [HOCO]+ (g) 600.63 597.54 ± 0.44 kJ/mol 45.0169 ± 0.0010 638-71-1*0 Ethylidene CH3CH (g, triplet) 361.30 354.29 ± 0.75 kJ/mol 28.0532 ± 0.0016 4218-50-2*1 Vinylium [CH2CH]+ (g) 1118.95 1115.50 ± 0.57 kJ/mol 27.0447 ± 0.0016 14604-48-9*0 Water H2O (l) -285.830 ± 0.026 kJ/mol 18.01528 ± 0.00033 7732-18-5*590 Hydroxymethylium [CH2OH]+ (g) 717.67 709.73 ± 0.19 kJ/mol 31.03337 ± 0.00088 18682-95-6*0 Cyanomethyl CH2CN (g) 263.32 260.44 ± 0.77 kJ/mol 40.0440 ± 0.0016 2932-82-3*0 Fluoroacetylene HCCF (g) 104.95 105.66 ± 0.41 kJ/mol 44.0277 ± 0.0016 2713-09-9*0 Peroxyformyl HC(O)OO (g, syn) -100.42 -105.72 ± 0.93 kJ/mol 61.0168 ± 0.0012 56240-83-6*1 Cyclopropene CH2(CHCH) (g) 292.20 283.47 ± 0.53 kJ/mol 40.0639 ± 0.0024 2781-85-3*0 n-Hexane CH3CH2CH2CH2CH2CH3 (g) -130.05 -166.92 ± 0.34 kJ/mol 86.1754 ± 0.0049 110-54-3*0 Trioxidane HOOOH (g, trans) -82.04 -90.88 ± 0.70 kJ/mol 50.01408 ± 0.00091 14699-99-1*1 Ketenyl HCCO (g) 177.06 178.16 ± 0.58 kJ/mol 41.0287 ± 0.0016 51095-15-9*0 Formic acid HC(O)OH (g) -371.11 -378.40 ± 0.22 kJ/mol 46.0254 ± 0.0010 64-18-6*0 Dioxidanide [HO2]- (g) -88.87 -91.53 ± 0.34 kJ/mol 33.00729 ± 0.00060 14691-59-9*0 Methyl formate HC(O)OCH3 (g, anti) -326.6 -339.1 ± 1.1 kJ/mol 60.0520 ± 0.0017 107-31-3*2 Trichloromethyl CCl3 (g) 72.03 71.55 ± 0.84 kJ/mol 118.3688 ± 0.0028 3170-80-7*0 1,1-Dichloroethane CH3CHCl2 (g) -120.30 -133.07 ± 0.44 kJ/mol 98.9586 ± 0.0024 75-34-3*0 Bromoform CHBr3 (g) 75.0 48.9 ± 1.2 kJ/mol 252.7306 ± 0.0031 75-25-2*0 Bromobenzene C6H5Br (g) 126.6 104.6 ± 1.3 kJ/mol 157.0079 ± 0.0049 108-86-1*0 Benzaldehyde C6H5C(O)H (g) -19.37 -37.17 ± 0.92 kJ/mol 106.1219 ± 0.0056 100-52-7*0 Chlorous acid HOClO (g) 25.73 20.68 ± 0.63 kJ/mol 68.4594 ± 0.0011 13898-47-0*0 Iodooxidanyl IO (g) 126.97 125.04 ± 0.82 kJ/mol 142.90387 ± 0.00030 14696-98-1*0 Carbon monoxide cation [CO]+ (g) 1238.306 1241.586 ± 0.026 kJ/mol 28.00955 ± 0.00085 12144-04-6*0 Azanide [NH2]- (g) 114.74 111.87 ± 0.30 kJ/mol 16.02317 ± 0.00016 17655-31-1*0 Aminooxy NH2O (g) 70.93 64.33 ± 0.76 kJ/mol 32.02202 ± 0.00034 13408-29-2*0 Hydroxyamidogen HNOH (g, trans) 101.5 94.7 ± 1.1 kJ/mol 32.02202 ± 0.00034 13940-32-4*1 Nitrate [ON(O)O]- (g) -300.20 -306.67 ± 0.60 kJ/mol 62.00549 ± 0.00090 14797-55-8*0 Cyanogen iodide ICN (g) 222.7 222.1 ± 1.6 kJ/mol 152.92191 ± 0.00080 506-78-5*0 Formyl anion [HCO]- (g) 11.59 11.98 ± 0.44 kJ/mol 29.01859 ± 0.00086 57340-31-5*0 2-Propynylidyne CCCH (g) 717.98 722.33 ± 0.82 kJ/mol 37.0400 ± 0.0024 53590-28-6*0 Cyclopentane CH2(CH2CH2CH2CH2) (g) -43.90 -76.46 ± 0.41 kJ/mol 70.1329 ± 0.0041 287-92-3*0 Ethoxy CH3CH2O (g, A 2A') 5.56 -8.87 ± 0.47 kJ/mol 45.0605 ± 0.0017 2154-50-9*52 Hypofluorite [FO]- (g) -108.84 -108.67 ± 0.48 kJ/mol 34.99835 ± 0.00030 12763-66-5*0 Chloromethylene CHCl (g, singlet) 320.26 320.55 ± 0.89 kJ/mol 48.4713 ± 0.0012 2108-20-5*2 Dibromomethane CH2Br2 (g) 25.5 4.1 ± 1.0 kJ/mol 173.8346 ± 0.0022 74-95-3*0 Trifluoromethylium [CF3]+ (g) 409.49 406.28 ± 0.47 kJ/mol 69.00536 ± 0.00080 18851-76-8*0 1,1-Difluoroethene CH2CF2 (g) -343.58 -350.64 ± 0.77 kJ/mol 64.0341 ± 0.0016 75-38-7*0 3-Buten-2-one CH3C(O)CHCH2 (g, trans) -95.56 -111.80 ± 0.87 kJ/mol 70.0898 ± 0.0032 78-94-4*1 Urea NH2C(O)NH2 (g) -218.26 -234.66 ± 0.42 kJ/mol 60.05534 ± 0.00091 57-13-6*0 Isocyanoacetylene HCCNC (g) 484.7 486.9 ± 1.1 kJ/mol 51.0468 ± 0.0024 66723-45-3*0 Chlorine trifluoride FCl(F)F (g) -158.6 -162.7 ± 1.2 kJ/mol 92.44791 ± 0.00090 7790-91-2*0 Iodine monochloride ICl (g) 19.024 17.391 ± 0.013 kJ/mol 162.35717 ± 0.00090 7790-99-0*0 Iodotrifluoromethane CF3I (g) -583.48 -589.36 ± 0.50 kJ/mol 195.91038 ± 0.00080 2314-97-8*0 Nitrogen atom cation N+ (g) 1872.907 1875.688 ± 0.024 kJ/mol 14.006191 ± 0.000070 14158-23-7*0 Azido radical NNN (g) 452.22 449.64 ± 0.60 kJ/mol 42.02022 ± 0.00021 12596-60-0*0 Trinitrogen cation [NNN]+ (g) 1519.39 1516.76 ± 0.89 kJ/mol 42.01967 ± 0.00021 12185-03-4*0 Oxonitrate anion [NO]- (g) 88.09 88.13 ± 0.25 kJ/mol 30.00669 ± 0.00031 14967-78-3*0 Nitrosyl ion [NO]+ (g) 984.485 984.480 ± 0.065 kJ/mol 30.00559 ± 0.00031 14452-93-8*0 Nitrogen sesquioxide ONN(O)O (g) 90.72 86.15 ± 0.15 kJ/mol 76.01168 ± 0.00091 10544-73-7*0 Hydrazoic acid HNNN (g) 297.87 291.57 ± 0.49 kJ/mol 43.02816 ± 0.00022 7782-79-8*0 Methylene anion [CH2]- (g) 328.17 328.60 ± 0.19 kJ/mol 14.02713 ± 0.00081 50928-07-9*0 Ethanium [C2H7]+ (g, bridged C2) 874.33 858.06 ± 0.62 kJ/mol 31.0764 ± 0.0017 24669-33-8*1 Hydrogen bromide HBr (aq) -120.93 ± 0.15 kJ/mol 80.9119 ± 0.0010 10035-10-6*800 Vinylidene CCH2 (g) 411.20 412.12 ± 0.32 kJ/mol 26.0373 ± 0.0016 2143-69-3*0 Acetylium [CH3CO]+ (g) 666.47 659.18 ± 0.45 kJ/mol 43.0441 ± 0.0016 15762-07-9*0 Hydrogen isocyanide HNC (g) 191.88 192.26 ± 0.36 kJ/mol 27.02538 ± 0.00081 6914-07-4*0 2-Butyne CH3CCCH3 (g) 159.35 146.38 ± 0.57 kJ/mol 54.0904 ± 0.0032 503-17-3*0 Hydroxymethylene HCOH (g, trans) 112.67 108.90 ± 0.28 kJ/mol 30.02598 ± 0.00087 19710-56-6*1 Carbonic acid C(O)(OH)2 (g, cis-cis) -602.76 -612.93 ± 0.75 kJ/mol 62.0248 ± 0.0012 463-79-6*1 Peroxyformate [HC(O)OO]- (g, syn) -340.96 -346.41 ± 0.96 kJ/mol 61.0174 ± 0.0012 104960-05-6*1 Isoprene CH2C(CH3)CHCH2 (g) 96.09 75.57 ± 0.67 kJ/mol 68.1170 ± 0.0040 78-79-5*0 1-Hydroxyethylium [CH3CHOH]+ (g, anti) 608.75 594.32 ± 0.39 kJ/mol 45.0600 ± 0.0017 18682-96-7*1 Dicarbon monoxide CCO (g, triplet) 377.13 381.17 ± 0.98 kJ/mol 40.0208 ± 0.0016 12071-23-7*1 Ethynol HCCOH (g, singlet) 95.47 92.99 ± 0.94 kJ/mol 42.0367 ± 0.0016 32038-79-2*2 Formyloxidanyl HC(O)O (g, 2A1) -125.86 -127.53 ± 0.56 kJ/mol 45.0174 ± 0.0010 16499-21-1*1 Glyoxal OCHCHO (g, trans) -207.73 -213.36 ± 0.61 kJ/mol 58.0361 ± 0.0017 107-22-2*1 Trimethylamine (CH3)3N (g) 1.60 -27.26 ± 0.90 kJ/mol 59.1103 ± 0.0025 75-50-3*0 1,1,1-Trichloroethane CH3CCl3 (g) -134.33 -144.91 ± 0.48 kJ/mol 133.4033 ± 0.0031 71-55-6*0 Tetrachloroethene CCl2CCl2 (g) -22.3 -23.2 ± 1.1 kJ/mol 165.8322 ± 0.0039 127-18-4*0 Chlorodifluoromethane CHClF2 (g) -476.02 -482.22 ± 0.98 kJ/mol 86.4681 ± 0.0012 75-45-6*0 Fluoromethylene CHF (g, singlet) 148.38 148.66 ± 0.43 kJ/mol 32.01704 ± 0.00080 13453-52-6*2 Fluoroformyl FCO (g) -176.62 -176.04 ± 0.37 kJ/mol 47.00850 ± 0.00085 1871-24-5*0 2-Bromoethanol BrCH2CH2OH (g) -196.43 -220.49 ± 0.53 kJ/mol 124.9645 ± 0.0019 540-51-2*0 Carbon suboxide OCCCO (g) -94.9 -92.8 ± 1.2 kJ/mol 68.0309 ± 0.0025 504-64-3*0 Propionaldehyde CH3CH2CHO (g) -171.38 -186.79 ± 0.25 kJ/mol 58.0791 ± 0.0025 123-38-6*0 Chloronium [HClH]+ (g) 881.3 878.2 ± 1.1 kJ/mol 37.46803 ± 0.00091 36658-55-6*0 Cyanomethylene HCCN (g, triplet) 479.9 483.2 ± 1.1 kJ/mol 39.0361 ± 0.0016 2612-62-6*1 Bromonium [HBrH]+ (g) 925.0 914.3 ± 1.5 kJ/mol 81.9193 ± 0.0010 36658-54-5*0 Hydrazine NH2NH2 (g) 111.57 97.42 ± 0.47 kJ/mol 32.04524 ± 0.00031 302-01-2*0 Hydrogen peroxide cation [H2O2]+ (g, trans) 897.23 890.25 ± 0.51 kJ/mol 34.01413 ± 0.00062 12325-10-9*1 Methanide [CH3]- (g) 141.08 137.63 ± 0.25 kJ/mol 15.03507 ± 0.00083 15194-58-8*0 Methyliumyl [CH2]+ (g) 1393.20 1394.06 ± 0.11 kJ/mol 14.02603 ± 0.00081 15091-72-2*0 Trioxidanide [HOOO]- (g, gauche) -120.0 -123.1 ± 1.6 kJ/mol 49.00669 ± 0.00090 89965-38-8*2 Vinyl anion [CH2CH]- (g) 237.00 232.58 ± 0.82 kJ/mol 27.0458 ± 0.0016 25012-81-1*0 Ethylidyne CH3C (g, quartet) 640.7 636.1 ± 1.1 kJ/mol 27.0452 ± 0.0016 67624-57-1*2 Aminomethylium [CH2NH2]+ (g) 763.86 751.88 ± 0.65 kJ/mol 30.04865 ± 0.00085 488821-23-4*0 Isocyanomethanide [CH2NC]- (g) 253.4 250.4 ± 1.1 kJ/mol 40.0446 ± 0.0016 81704-80-5*0 1-Methylethenyl CH3CCH2 (g) 262.98 252.58 ± 0.77 kJ/mol 41.0718 ± 0.0024 15552-77-9*0 trans-2-Butene CH3CHCHCH3 (g, trans) 9.38 -11.18 ± 0.41 kJ/mol 56.1063 ± 0.0032 624-64-6*0 iso-Pentane CH3CH2CH(CH3)2 (g) -119.17 -153.22 ± 0.43 kJ/mol 72.1488 ± 0.0041 78-78-4*0 1-Hydroxyethyl CH3CHOH (g, gauche-syn) -41.30 -54.77 ± 0.80 kJ/mol 45.0605 ± 0.0017 2348-46-1*2 Protonated oxirane [(CH2CH2)OH]+ (g) 725.35 709.18 ± 0.62 kJ/mol 45.0600 ± 0.0017 *38607-31-7*0 Methanediol CH2(OH)2 (g, conrot gauche) -379.37 -393.57 ± 0.93 kJ/mol 48.0413 ± 0.0010 463-57-0*1 Methoxyethane CH3CH2OCH3 (g) -194.29 -217.18 ± 0.55 kJ/mol 60.0950 ± 0.0025 540-67-0*0 Acetic acid CH3C(O)OH (g, anti) -397.87 -411.65 ± 0.84 kJ/mol 60.0520 ± 0.0017 64-19-7*2 Acetyl chloride CH3C(O)Cl (g) -232.60 -241.59 ± 0.33 kJ/mol 78.4973 ± 0.0019 75-36-5*0 Chlorohydroxymethyl CH(Cl)OH (g, syn-gauche) -54.9 -60.9 ± 1.1 kJ/mol 65.4787 ± 0.0012 147139-06-8*1 1,1-Dichloroethene CH2CCl2 (g) 8.93 2.94 ± 0.49 kJ/mol 96.9427 ± 0.0024 75-35-4*0 Dichlorodifluoromethane CF2Cl2 (g) -489.46 -493.65 ± 0.67 kJ/mol 120.9129 ± 0.0020 75-71-8*0 Fluorodichloromethane CHFCl2 (g) -278.21 -283.66 ± 0.91 kJ/mol 102.9224 ± 0.0020 75-43-4*0 Difluoromethylene CF2 (g, singlet) -193.91 -193.44 ± 0.38 kJ/mol 50.00751 ± 0.00080 2154-59-8*2 Fluoromethylene CHF (g, triplet) 210.36 210.70 ± 0.66 kJ/mol 32.01704 ± 0.00080 13453-52-6*1 Formyl fluoride CHFO (g) -378.64 -382.23 ± 0.31 kJ/mol 48.01644 ± 0.00086 1493-02-3*0 Benzyl C6H5CH2 (g) 229.93 211.11 ± 0.60 kJ/mol 91.1305 ± 0.0056 2154-56-5*0 Methyl nitrite CH3ONO (g, cis) -55.65 -67.44 ± 0.46 kJ/mol 61.0401 ± 0.0010 624-91-9*2 Hydrogen chloride HCl (aq) -166.991 ± 0.023 kJ/mol 36.46064 ± 0.00090 7647-01-0*800 Carbamoyl NH2CO (g) -7.52 -13.93 ± 0.83 kJ/mol 44.03272 ± 0.00087 2858-51-7*0 Peroxyhypochlorous acid HOOCl (g) 3.94 -1.33 ± 0.95 kJ/mol 68.4594 ± 0.0011 67952-07-2*0 Hypoiodite [IO]- (g) -102.48 -104.29 ± 0.88 kJ/mol 142.90442 ± 0.00030 15065-65-3*0 Dinitrogen cation [N2]+ (g) 1503.311 1503.312 ± 0.000 kJ/mol 28.01293 ± 0.00014 13966-04-6*0 Carbon dioxide cation [CO2]+ (g) 936.093 936.927 ± 0.017 kJ/mol 44.00895 ± 0.00100 12181-61-2*0 Ammonium [NH4]+ (aq) -133.075 ± 0.056 kJ/mol 18.03795 ± 0.00029 14798-03-9*800 Hydrazino NH2NH (g) 234.81 224.29 ± 0.78 kJ/mol 31.03730 ± 0.00025 13598-46-4*0 Methylidyne anion [CH]- (g) 475.74 479.07 ± 0.22 kJ/mol 13.01919 ± 0.00080 28604-54-8*0 Methylamidogen CH3NH (g) 187.46 176.81 ± 0.47 kJ/mol 30.04920 ± 0.00085 15622-51-2*0 Hydrogen isocyanide cation [HNC]+ (g) 1352.9 1352.8 ± 1.3 kJ/mol 27.02483 ± 0.00081 74158-11-5*0 iso-Propylium [CH3CHCH3]+ (g) 822.90 805.82 ± 0.25 kJ/mol 43.0871 ± 0.0024 19252-53-0*0 n-Propylide [CH3CH2CH2]- (g) 122.9 105.2 ± 1.2 kJ/mol 43.0882 ± 0.0024 59513-13-2*0 1,2-Propadienyl anion [CH2CCH]- (g) 265.64 262.59 ± 0.71 kJ/mol 39.0565 ± 0.0024 64066-06-4*0 Propargylenide [HCCCH]- (g, transoid 2B) 434.4 436.9 ± 1.1 kJ/mol 38.0485 ± 0.0024 82906-05-6*1 Dichloride [Cl2]- (g) -229.8 -228.7 ± 1.4 kJ/mol 70.9059 ± 0.0018 12595-89-0*0 t-Butyl (CH3)3C (g) 75.59 50.30 ± 0.66 kJ/mol 57.1143 ± 0.0033 1605-73-8*0 neo-Pentane C(CH3)4 (g) -134.63 -167.51 ± 0.40 kJ/mol 72.1488 ± 0.0041 463-82-1*0 1-Butyne CH3CH2CCH (g) 179.52 165.94 ± 0.65 kJ/mol 54.0904 ± 0.0032 107-00-6*0 Chlorine atom cation Cl+ (g) 1370.806 1372.602 ± 0.0011 kJ/mol 35.45215 ± 0.00090 24203-47-2*0 2-Hydroxyethyl CH2CH2OH (g, gauche-anti) -10.79 -23.42 ± 0.82 kJ/mol 45.0605 ± 0.0017 4422-54-2*2 Ketene CH2CO (g, triplet) 182.0 177.0 ± 1.1 kJ/mol 42.0367 ± 0.0016 463-51-4*1 Methanediol CH2(OH)2 (g, disrot gauche) -369.06 -382.22 ± 0.96 kJ/mol 48.0413 ± 0.0010 463-57-0*2 Chloro hypochlorite ClOCl (g) 79.78 77.97 ± 0.36 kJ/mol 86.9048 ± 0.0018 7791-21-1*0 Methoxyethene CH2CHOCH3 (g, cis) -89.0 -106.9 ± 1.1 kJ/mol 58.0791 ± 0.0025 107-25-5*2 Methyl acetate CH3C(O)OCH3 (g, anti) -363.4 -382.2 ± 1.2 kJ/mol 74.0785 ± 0.0025 79-20-9*2 Carboxymethyl CH2C(O)OH (g, syn) -227.4 -237.3 ± 1.2 kJ/mol 59.0440 ± 0.0017 2887-46-9*1 (Methylamino)methyl CH3NHCH2 (g) 167.69 151.24 ± 0.97 kJ/mol 44.0758 ± 0.0017 31277-24-4*0 Dimethylamidogen (CH3)2N (g) 173.8 156.5 ± 1.5 kJ/mol 44.0758 ± 0.0017 15337-44-7*0 Cyanoamidogen HNCN (g) 323.9 321.4 ± 1.4 kJ/mol 41.03212 ± 0.00082 12347-01-2*0 Bromotrichloromethane CCl3Br (g) -32.57 -41.72 ± 0.59 kJ/mol 198.2728 ± 0.0030 75-62-7*0 Chloromethylidyne CCl (g) 430.42 434.18 ± 0.67 kJ/mol 47.4634 ± 0.0012 3889-76-7*0 Hydroperoxonium [H2OOH]+ (g, trans) 738.1 727.8 ± 1.2 kJ/mol 35.02207 ± 0.00064 70850-26-9*1 Chloromethanol CH2(Cl)OH (g) -232.4 -242.6 ± 1.2 kJ/mol 66.4866 ± 0.0013 15454-33-8*0 Chloromethoxy CH2(Cl)O (g) -12.0 -18.9 ± 1.1 kJ/mol 65.4787 ± 0.0012 114282-89-2*0 Chlorine pentafluoride FCl(F)(F)(F)F (g) -226.1 -234.2 ± 1.7 kJ/mol 130.44472 ± 0.00090 13637-63-3*0 Tetraiodomethane CI4 (g) 332.1 326.9 ± 4.1 kJ/mol 519.62858 ± 0.00081 507-25-5*0 Fluorotrichloromethane CCl3F (g) -285.27 -288.43 ± 0.78 kJ/mol 137.3672 ± 0.0028 75-69-4*0 Chlorooxy hypochlorite ClOOCl (g) 134.56 131.32 ± 0.56 kJ/mol 102.9042 ± 0.0019 12292-23-8*0 2-Chloroethanol ClCH2CH2OH (g) -249.84 -266.56 ± 0.59 kJ/mol 80.5132 ± 0.0019 107-07-3*0 o-Benzyne C6H4 (g, singlet) 467.91 458.99 ± 0.88 kJ/mol 76.0960 ± 0.0048 462-80-6*2 Tropyl CH(CHCHCHCHCHCH) (g) 295.7 278.2 ± 1.1 kJ/mol 91.1305 ± 0.0056 3551-27-7*0 Iodobenzene C6H5I (g) 177.66 161.67 ± 0.99 kJ/mol 204.0084 ± 0.0048 591-50-4*0 Acetonyl CH3C(O)CH2 (g) -19.05 -31.76 ± 0.98 kJ/mol 57.0712 ± 0.0024 3122-07-4*0 Trifluoroethene CF2CHF (g) -493.1 -498.2 ± 1.6 kJ/mol 82.0245 ± 0.0016 359-11-5*0 Isocyanoethene CH2CHNC (g) 285.04 278.53 ± 0.97 kJ/mol 53.0627 ± 0.0024 14668-82-7*0 1-Isocyanoethylidene CH3CNC (g, singlet) 527.7 523.0 ± 1.1 kJ/mol 53.0627 ± 0.0024 *498544-34-6*2 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) -206.64 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*800 Chlorodioxidanyl ClOO (g) 103.91 102.82 ± 0.37 kJ/mol 67.4515 ± 0.0011 17376-09-9*0 Oxoammoniumyl [HNO]+ (g) 1092.45 1089.53 ± 0.67 kJ/mol 31.01353 ± 0.00032 63559-87-5*0 Peroxynitrous acid HOONO (g, trans, perp) 7.77 0.69 ± 0.41 kJ/mol 63.01288 ± 0.00091 14691-52-2*1 Carbon anion C- (g) 589.620 594.766 ± 0.047 kJ/mol 12.01125 ± 0.00080 14337-00-9*0 Perchloryl OCl(O)O (g) 191.69 186.01 ± 0.61 kJ/mol 83.4509 ± 0.0013 13932-10-0*0 Chlorate [OCl(O)O]- (g) -207.3 -212.8 ± 1.6 kJ/mol 83.4514 ± 0.0013 14866-68-3*0 Ethylidyne CH3C (g) 508.53 504.83 ± 0.80 kJ/mol 27.0452 ± 0.0016 67624-57-1*0 Ethynylium [CCH]+ (g) 1687.58 1690.91 ± 0.16 kJ/mol 25.0288 ± 0.0016 16456-59-0*0 Methylamidogen anion [CH3NH]- (g) 145.17 134.35 ± 0.66 kJ/mol 30.04975 ± 0.00085 54448-39-4*0 Iminomethyl cation [HCNH]+ (g) 953.3 949.3 ± 1.4 kJ/mol 28.03277 ± 0.00082 196216-36-1*0 2-Hydrotrioxy OO(H)O (g) 299.6 293.9 ± 1.2 kJ/mol 49.00614 ± 0.00090 *12500-78-6*0 Chloroacetylene HCCCl (g) 228.15 229.01 ± 0.72 kJ/mol 60.4820 ± 0.0018 593-63-5*0 Water dimer (H2O)2 (g) -491.086 -499.125 ± 0.052 kJ/mol 36.03056 ± 0.00066 25655-83-8*0 Methylperoxy anion [CH3OO]- (g) -89.88 -100.02 ± 0.64 kJ/mol 47.0339 ± 0.0010 35683-44-4*0 1-Propenyl CH3CHCH (g, cis) 278.22 267.38 ± 0.78 kJ/mol 41.0718 ± 0.0024 6067-68-1*2 Propylidyne CH3CH2C (g, doublet) 492.4 482.8 ± 1.2 kJ/mol 41.0718 ± 0.0024 85056-54-8*1 Propargylenide [HCCCH]- (g, cisoid 2A) 436.9 439.4 ± 1.1 kJ/mol 38.0485 ± 0.0024 82906-05-6*2 Chloric acid HOCl(O)O (g) 2.1 -5.0 ± 1.6 kJ/mol 84.4588 ± 0.0013 7790-93-4*0 2-Propyn-1-ylium-1-ylidene [CCCH]+ (g) 1598.1 1602.5 ± 1.3 kJ/mol 37.0395 ± 0.0024 75104-46-0*0 Difluoride [F2]- (g) -291.0 -290.2 ± 1.5 kJ/mol 37.9973550 ± 0.0000010 12184-85-9*0 Oxoethanide [CH3CO]- (g) -44.0 -49.6 ± 1.3 kJ/mol 43.0452 ± 0.0016 78944-68-0*0 Oxirene O(CHCH) (g, singlet) 273.18 271.02 ± 0.92 kJ/mol 42.0367 ± 0.0016 157-18-6*2 Hydrogen fluoride HF (aq, 20 H2O) -321.04 ± 0.16 kJ/mol 20.006343 ± 0.000070 7664-39-3*818 Hydroxyformyl HOCO (g, cis) -174.30 -177.33 ± 0.51 kJ/mol 45.0174 ± 0.0010 2564-86-5*2 Hydroxyformyl anion [HOCO]- (g, cis) -319.46 -322.04 ± 0.59 kJ/mol 45.0180 ± 0.0010 78944-70-4*2 Ethoxyethane CH3CH2OCH2CH3 (g) -222.88 -250.30 ± 0.82 kJ/mol 74.1216 ± 0.0033 60-29-7*0 Fluoronium [HFH]+ (g, singlet) 774.11 771.17 ± 0.88 kJ/mol 21.01373 ± 0.00014 12206-67-6*2 Acetone enol CH3C(OH)CH2 (g, syn) -151.8 -169.2 ± 1.1 kJ/mol 58.0791 ± 0.0025 29456-04-0*1 Acetate [CH3C(O)O]- (g) -496.6 -505.7 ± 1.2 kJ/mol 59.0446 ± 0.0017 71-50-1*0 (Dimethylamino)methyl (CH3)2NCH2 (g) 165.4 142.4 ± 1.4 kJ/mol 58.1024 ± 0.0025 30208-47-0*0 Trioxidane HOOOH (g, cis) -72.75 -81.24 ± 0.83 kJ/mol 50.01408 ± 0.00091 14699-99-1*2 Bromanylium Br+ (g) 1257.775 1251.712 ± 0.056 kJ/mol 79.90345 ± 0.00100 22541-56-6*0 Chloromethide [CH2Cl]- (g) 56.3 53.0 ± 2.0 kJ/mol 49.4798 ± 0.0012 60291-29-4*0 Hexachloroethane CCl3CCl3 (g) -147.0 -149.4 ± 1.3 kJ/mol 236.7376 ± 0.0056 67-72-1*0 cis-1,2-Dichloroethene CHClCHCl (g, cis) 3.46 -2.54 ± 0.54 kJ/mol 96.9427 ± 0.0024 156-59-2*0 Dichloroacetylene ClCCCl (g) 230.07 233.38 ± 0.95 kJ/mol 94.9268 ± 0.0024 7572-29-4*0 Difluoromethylene CF2 (g) -193.91 -193.44 ± 0.38 kJ/mol 50.00751 ± 0.00080 2154-59-8*0 Hexafluoroethane CF3CF3 (g) -1334.20 -1342.49 ± 0.99 kJ/mol 138.0118 ± 0.0016 76-16-4*0 1,1-Difluoroethane CH3CHF2 (g) -489.00 -502.72 ± 0.56 kJ/mol 66.0500 ± 0.0016 75-37-6*0 2-Fluoroethanol FCH2CH2OH (g) -405.75 -422.99 ± 0.99 kJ/mol 64.0589 ± 0.0017 371-62-0*0 1,3-Butadiyne HCCCCH (g) 457.83 459.56 ± 0.77 kJ/mol 50.0587 ± 0.0032 460-12-8*0 Benzylide [C6H5CH2]- (g) 141.78 122.86 ± 0.44 kJ/mol 91.1310 ± 0.0056 18860-15-6*0 Ethylbenzene C6H5CH2CH3 (g) 58.17 29.71 ± 0.55 kJ/mol 106.1650 ± 0.0064 100-41-4*0 Phenylethene C6H5CHCH2 (g) 169.66 148.32 ± 0.55 kJ/mol 104.1491 ± 0.0064 100-42-5*0 Phenylacetylene C6H5CCH (g) 332.4 317.2 ± 1.1 kJ/mol 102.1332 ± 0.0064 536-74-3*0 Acetonate [CH3C(O)CH2]- (g) -187.86 -201.41 ± 0.98 kJ/mol 57.0717 ± 0.0024 24262-31-5*0 Propadienone CH2CCO (g) 131.94 130.30 ± 0.79 kJ/mol 54.0474 ± 0.0024 61244-93-7*0 Oxomethaniminium [NH2CO]+ (g) 695.1 688.5 ± 1.0 kJ/mol 44.03217 ± 0.00087 59348-22-0*0 Nitrosomethane CH3NO (g) 81.3 71.4 ± 1.3 kJ/mol 45.04066 ± 0.00088 865-40-7*0 1-Cyanoethylidene CH3CCN (g, singlet) 475.6 470.5 ± 1.1 kJ/mol 53.0627 ± 0.0024 498544-34-6*2 3-Imino-2-propen-1-ylidene CHCHCNH (g, syn-singlet) 530.6 525.8 ± 1.2 kJ/mol 53.0627 ± 0.0024 916765-05-4*11 2-(Methylidyneamino)ethenyl CHCHNCH (g, anti-singlet) 600.6 595.5 ± 1.2 kJ/mol 53.0627 ± 0.0024 123416-74-0*11 1-Cyanovinyl CH2CCN (g) 419.7 419.6 ± 1.3 kJ/mol 52.0547 ± 0.0024 15091-87-9*0 1-Cyanovinyl anion [CH2CCN]- (g) 224.4 221.6 ± 1.3 kJ/mol 52.0553 ± 0.0024 36259-97-9*0 2-Cyanovinyl CHCHCN (g, anti) 447.9 445.4 ± 1.2 kJ/mol 52.0547 ± 0.0024 189141-20-6*1 Dioxaziridinyl N(OO) (g) 355.1 352.6 ± 1.4 kJ/mol 46.00554 ± 0.00060 66252-29-7*0 Nitroxyl ON(O)O (g) 79.40 74.14 ± 0.19 kJ/mol 62.00494 ± 0.00090 12033-49-7*0 Azanylium [NH3]+ (g) 944.273 937.318 ± 0.029 kJ/mol 17.03001 ± 0.00022 19496-55-0*0 Isodiazene NNH2 (g) 307.52 300.44 ± 0.75 kJ/mol 30.02936 ± 0.00020 28647-38-3*0 Nitryl hydride HN(O)O (g) -37.1 -44.1 ± 1.5 kJ/mol 47.01348 ± 0.00061 90266-90-3*0 Carbon cation C+ (g) 1797.849 1803.447 ± 0.047 kJ/mol 12.01015 ± 0.00080 14067-05-1*0 Bromochlorane BrCl (g) 21.879 14.435 ± 0.060 kJ/mol 115.3567 ± 0.0013 13863-41-7*0 Oxygen atom O (g, singlet) 436.666 438.523 ± 0.0021 kJ/mol 15.99940 ± 0.00030 17778-80-2*2 Methyliumylidene [CH]+ (g) 1619.754 1623.097 ± 0.055 kJ/mol 13.01809 ± 0.00080 24361-82-8*0 Dioxygen anion [O2]- (g) -43.36 -42.72 ± 0.17 kJ/mol 31.99935 ± 0.00060 11062-77-4*0 Ethylidyne CH3C (g, doublet) 508.53 504.83 ± 0.80 kJ/mol 27.0452 ± 0.0016 67624-57-1*1 Vinylidene anion [CCH2]- (g) 364.02 363.83 ± 0.51 kJ/mol 26.0378 ± 0.0016 66295-36-1*0 Methyleneamidogen CH2N (g) 241.94 238.28 ± 0.67 kJ/mol 28.03332 ± 0.00082 15845-29-1*0 (E)-Iminomethyl HCNH (g, trans) 275.82 272.21 ± 0.71 kJ/mol 28.03332 ± 0.00082 54980-10-8*0 Nitrilomethylium [CN]+ (g) 1776.9 1780.4 ± 1.3 kJ/mol 26.01689 ± 0.00080 12539-57-0*0 Cyanomethanide [CH2CN]- (g) 114.17 111.34 ± 0.77 kJ/mol 40.0446 ± 0.0016 21438-99-3*0 Methanol cation [CH3OH]+ (g) 856.81 846.49 ± 0.32 kJ/mol 32.04131 ± 0.00090 12538-91-9*0 Methyloxonium [CH3OH2]+ (g) 588.5 574.3 ± 1.2 kJ/mol 33.04925 ± 0.00092 17836-08-7*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) -596.90 -607.01 ± 0.83 kJ/mol 62.0248 ± 0.0012 463-79-6*2 Carbonic acid C(O)(OH)2 (g, trans-trans) -561.67 -570.52 ± 0.97 kJ/mol 62.0248 ± 0.0012 463-79-6*3 Hydrogen carbonate [HOC(O)O]- (g) -720.5 -726.9 ± 1.4 kJ/mol 61.0174 ± 0.0012 71-52-3*0 n-Propylium [CH3CH2CH2]+ (g) 856.94 838.66 ± 0.86 kJ/mol 43.0871 ± 0.0024 19252-52-9*0 Allyl anion [CH2CHCH2]- (g) 134.12 123.11 ± 0.24 kJ/mol 41.0723 ± 0.0024 1724-46-5*0 Cyclopropyl CH(CH2CH2) (g) 303.3 290.7 ± 1.5 kJ/mol 41.0718 ± 0.0024 2417-82-5*0 Propylidyne CH3CH2C (g, quartet) 624.5 613.0 ± 1.3 kJ/mol 41.0718 ± 0.0024 85056-54-8*2 1-Propynylide [CH3CC]- (g) 263.89 260.31 ± 0.98 kJ/mol 39.0565 ± 0.0024 36147-87-2*0 1-Propen-1-yl-3-ylidene CHCHCH (g, c-c quartet) 657.4 653.9 ± 1.5 kJ/mol 39.0559 ± 0.0024 84654-90-0*11 sec-Butyl CH3CH2CHCH3 (g) 90.83 66.07 ± 0.95 kJ/mol 57.1143 ± 0.0033 2348-55-2*0 Hypochloroperoxoous acid, hydroxy ester HOOOCl (g, syn) 49.1 42.2 ± 1.9 kJ/mol 84.4588 ± 0.0013 928652-99-7*1 Oxidanylium [OH]+ (g) 1293.188 1293.217 ± 0.035 kJ/mol 17.00679 ± 0.00031 12259-29-9*0 1,2-Butadiene CH3CHCCH2 (g) 175.79 162.29 ± 0.50 kJ/mol 54.0904 ± 0.0032 590-19-2*0 Cyclohexane CH2(CH2CH2CH2CH2CH2) (g) -83.57 -123.13 ± 0.36 kJ/mol 84.1595 ± 0.0049 110-82-7*0 Trioxidanyl HOOO (g, trans) 25.32 23.33 ± 0.13 kJ/mol 49.00614 ± 0.00090 12500-78-6*1 Oxirene O(CHCH) (g, t-triplet) 387.9 383.6 ± 1.4 kJ/mol 42.0367 ± 0.0016 157-18-6*11 Oxiranylidene CH2(CO) (g, singlet) 213.5 209.3 ± 1.4 kJ/mol 42.0367 ± 0.0016 50983-85-2*2 Oxoethylidene HCC(O)H (g, syn-triplet) 261.2 257.7 ± 1.6 kJ/mol 42.0367 ± 0.0016 39920-84-8*12 Dioxirane CH2(OO) (g) 9.41 1.74 ± 0.55 kJ/mol 46.0254 ± 0.0010 157-26-6*0 Hydroxyformyl anion [HOCO]- (g, trans) -313.63 -315.43 ± 0.60 kJ/mol 45.0180 ± 0.0010 78944-70-4*1 Ethoxyethene CH2CHOCH2CH3 (g, cis-trans) -117.4 -141.2 ± 1.5 kJ/mol 72.1057 ± 0.0033 109-92-2*2 Cyanic acid HOCN (g) -12.31 -15.03 ± 0.48 kJ/mol 43.02478 ± 0.00086 420-05-3*0 Isofulminic acid HONC (g) 235.26 233.56 ± 0.48 kJ/mol 43.02478 ± 0.00086 506-85-4*0 Acetic acid CH3C(O)OH (g) -418.86 -432.98 ± 0.43 kJ/mol 60.0520 ± 0.0017 64-19-7*0 Ethyl formate HC(O)OCH2CH3 (g, syn) -375.2 -393.9 ± 1.2 kJ/mol 74.0785 ± 0.0025 109-94-4*1 Methoxyoxomethyl CH3OCO (g, anti-staggered) -152.5 -160.5 ± 1.5 kJ/mol 59.0440 ± 0.0017 16481-04-2*1 (Formyloxy)methyl HC(O)OCH2 (g, syn) -151.9 -160.0 ± 1.3 kJ/mol 59.0440 ± 0.0017 3122-12-1*1 Ethylene glycol (CH2OH)2 (g) -369.75 -389.37 ± 0.40 kJ/mol 62.0678 ± 0.0018 107-21-1*0 Dioxoethyl OCHCO (g) -63.6 -65.0 ± 1.3 kJ/mol 57.0281 ± 0.0017 702699-38-5*0 (Methylamino)methyl cation [CH3NHCH2]+ (g) 728.98 710.37 ± 0.99 kJ/mol 44.0752 ± 0.0017 *31277-24-4*0 Iodine monobromide IBr (g) 49.715 40.768 ± 0.067 kJ/mol 206.8085 ± 0.0010 7789-33-5*0 Diazomethyl HCNN (g) 470.6 468.1 ± 1.5 kJ/mol 41.03212 ± 0.00082 20813-32-5*0 Isocyanoamidogen HNNC (g) 491.1 489.1 ± 1.5 kJ/mol 41.03212 ± 0.00082 947408-73-3*0 Dichloromethyl CHCl2 (g) 92.17 90.25 ± 0.88 kJ/mol 83.9240 ± 0.0020 3474-12-2*0 Chloromethyl CH2Cl (g) 118.36 115.29 ± 0.87 kJ/mol 49.4793 ± 0.0012 6806-86-6*0 Methyl hypochlorite CH3OCl (g) -53.1 -63.1 ± 1.4 kJ/mol 66.4866 ± 0.0013 593-78-2*0 1,2-Dichloroethane CH2ClCH2Cl (g) -118.58 -130.52 ± 0.54 kJ/mol 98.9586 ± 0.0024 107-06-2*0 Chlorofluoromethane CH2FCl (g) -256.1 -263.3 ± 1.1 kJ/mol 68.4777 ± 0.0012 593-70-4*0 Difluoromethyliumyl [CF2]+ (g) 908.18 908.60 ± 0.78 kJ/mol 50.00696 ± 0.00080 54250-40-7*0 Fluoromethyliumylidene [CF]+ (g) 1122.90 1126.12 ± 0.46 kJ/mol 31.00855 ± 0.00080 33412-11-2*0 1,2-Difluoroacetylene FCCF (g) 2.86 5.69 ± 0.65 kJ/mol 62.0182 ± 0.0016 689-99-6*0 Formyl chloride CHClO (g) -179.99 -183.20 ± 0.77 kJ/mol 64.4707 ± 0.0012 2565-30-2*0 Chloroformyl ClCO (g) -21.92 -20.53 ± 0.49 kJ/mol 63.4628 ± 0.0012 2602-42-8*0 Hydroxyde [OH]- (aq) -230.014 ± 0.029 kJ/mol 17.00789 ± 0.00031 14280-30-9*800 Ozonide [OOO]- (g) -58.48 -60.84 ± 0.21 kJ/mol 47.99875 ± 0.00090 12596-80-4*0 o-Benzyne anion [C6H4]- (g) 413.54 404.43 ± 0.97 kJ/mol 76.0965 ± 0.0048 100569-88-8*0 Cycloheptene CH2(CHCHCH2CH2CH2CH2 (g) 28.15 -9.08 ± 0.75 kJ/mol 96.1702 ± 0.0057 628-92-2*0 Cycloheptatriene CH2(CHCHCHCHCHCH) (g) 207.03 183.61 ± 0.96 kJ/mol 92.1384 ± 0.0056 544-25-2*0 Fluorobenzene cation [C6H5F]+ (g) 788.89 773.87 ± 0.89 kJ/mol 96.1018 ± 0.0048 34468-25-2*0 Nitrosobenzene C6H5NO (g) 215.7 198.7 ± 1.2 kJ/mol 107.1100 ± 0.0048 586-96-9*0 Nitromethyl CH2N(O)O (g) 138.9 129.5 ± 1.2 kJ/mol 60.0321 ± 0.0010 16787-85-2*0 Methylketene CH3CHCO (g) -54.7 -64.2 ± 1.1 kJ/mol 56.0633 ± 0.0024 6004-44-0*0 Acrolein CH2CHCHO (g, trans) -55.3 -65.7 ± 1.2 kJ/mol 56.0633 ± 0.0024 107-02-8*1 Formaldoxime CH2NOH (g, trans) 30.7 20.1 ± 1.4 kJ/mol 45.04066 ± 0.00088 75-17-2*1 Trioxygen difluoride FOOOF (g, trans) 112.2 106.5 ± 1.1 kJ/mol 85.99501 ± 0.00090 16829-28-0*1 2-Cyanovinyl CHCHCN (g, syn) 447.8 445.3 ± 1.3 kJ/mol 52.0547 ± 0.0024 189141-20-6*2 Diazenyl NNH (g) 252.16 249.24 ± 0.47 kJ/mol 29.02142 ± 0.00016 36882-13-0*0 Iodide I- (aq) -56.826 ± 0.090 kJ/mol 126.905019 ± 0.000030 20461-54-5*800 Fluoride F- (aq) -334.50 ± 0.16 kJ/mol 18.99895178 ± 0.00000050 16984-48-8*800 Water anion [(H)(OH)]- (g, vdW ?) 31.3 29.8 ± 3.1 kJ/mol 18.01583 ± 0.00033 12259-30-2*100 Peroxynitric acid HOON(O)O (g) -42.6 -53.0 ± 1.3 kJ/mol 79.0123 ± 0.0012 26404-66-0*0 Nitrosyl chloride ClNO (g) 54.451 52.549 ± 0.067 kJ/mol 65.45884 ± 0.00095 2696-92-6*0 Carbon dioxide CO2 (g, triplet) 49.8 50.6 ± 1.1 kJ/mol 44.00950 ± 0.00100 124-38-9*1 Methane cation [CH4]+ (g) 1150.669 1144.286 ± 0.065 kJ/mol 16.04191 ± 0.00085 20741-88-2*0 Ethanium [C2H7]+ (g) 874.33 858.09 ± 0.62 kJ/mol 31.0764 ± 0.0017 24669-33-8*0 Hydrogen difluoride (F)(HF) (g, lin) -198.5 -198.4 ± 1.2 kJ/mol 39.004746 ± 0.000070 12528-21-1*1 Acetylene cation [HCCH]+ (g) 1328.83 1328.17 ± 0.13 kJ/mol 26.0367 ± 0.0016 25641-79-6*0 1-Ethylium-1-ylidene [CH3C]+ (g) 1329.6 1328.2 ± 1.2 kJ/mol 27.0447 ± 0.0016 78949-84-5*0 Ethylidyne anion [CH3C]- (g) 457.0 452.9 ± 1.2 kJ/mol 27.0458 ± 0.0016 117768-70-4*0 Isocyanomethyl CH2NC (g) 363.3 360.9 ± 1.3 kJ/mol 40.0440 ± 0.0016 70971-59-4*0 Dioxidenium [HO2]+ (g) 1110.87 1107.98 ± 0.11 kJ/mol 33.00619 ± 0.00060 12207-52-2*0 Methyloxoniumylidene [CH3O]+ (g) 1062.72 1054.91 ± 0.75 kJ/mol 31.03337 ± 0.00088 58157-09-8*0 Hydroxymethylene HCOH (g, cis) 131.09 127.35 ± 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) 217.26 217.64 ± 0.69 kJ/mol 29.01804 ± 0.00086 71080-92-7*0 Chlorine difluoride FClF (g) -47.0 -48.2 ± 1.4 kJ/mol 73.44951 ± 0.00090 24801-48-7*0 Chloryl hydride HCl(O)O (g) 197.6 191.2 ± 1.6 kJ/mol 68.4594 ± 0.0011 174365-32-3*0 1-Methylethylidene CH3CCH3 (g, singlet) 316.2 302.3 ± 2.0 kJ/mol 42.0797 ± 0.0024 40852-89-9*2 Propylidene CH3CH2CH (g, triplet) 349.4 335.7 ± 1.4 kJ/mol 42.0797 ± 0.0024 6700-78-3*1 Allylium [CH2CHCH2]+ (g) 964.58 953.02 ± 0.45 kJ/mol 41.0713 ± 0.0024 1724-44-3*0 1-Propenyl CH3CHCH (g, trans) 280.26 269.44 ± 0.80 kJ/mol 41.0718 ± 0.0024 6067-68-1*1 Propargylium [CH2CCH]+ (g) 1193.44 1190.62 ± 0.37 kJ/mol 39.0554 ± 0.0024 21540-27-2*0 Cycloprop-1-enyl CH2(CHC) (g) 527.51 523.12 ± 0.67 kJ/mol 39.0559 ± 0.0024 19528-44-0*0 Iodine cation I+ (g) 1115.549 1115.149 ± 0.0062 kJ/mol 126.903921 ± 0.000030 22541-93-1*0 n-Butyl anion [CH3CH2CH2CH2]- (g) 105.8 80.9 ± 1.3 kJ/mol 57.1148 ± 0.0033 79431-01-9*0 sec-Butyl anion [CH3CH2CHCH3]- (g) 103.0 78.5 ± 1.3 kJ/mol 57.1148 ± 0.0033 79431-00-8*0 Bifluoride [(HF)(F)]- (g, singlet) -481.8 -480.6 ± 1.9 kJ/mol 39.005295 ± 0.000070 *18130-74-0*2 Cyclobutane CH2(CH2CH2CH2) (g) 52.34 27.80 ± 0.41 kJ/mol 56.1063 ± 0.0032 287-23-0*0 Cyclobutene CH2(CH2CHCH) (g) 177.27 160.22 ± 0.88 kJ/mol 54.0904 ± 0.0032 822-35-5*0 Cyclopentene CH2(CH2CHCHCH2) (g) 59.43 35.16 ± 0.46 kJ/mol 68.1170 ± 0.0040 142-29-0*0 n-Heptane CH3(CH2)5CH3 (g) -145.65 -187.53 ± 0.48 kJ/mol 100.2019 ± 0.0057 142-82-5*0 n-Octane CH3(CH2)6CH3 (g) -161.41 -208.25 ± 0.67 kJ/mol 114.2285 ± 0.0065 111-65-9*0 1-Hydroxyethylium [CH3CHOH]+ (g, syn) 610.8 596.3 ± 1.1 kJ/mol 45.0600 ± 0.0017 18682-96-7*2 Ethenol CH2CHOH (g, anti) -108.28 -119.07 ± 0.77 kJ/mol 44.0526 ± 0.0017 557-75-5*2 Vinyl alcohol cation [CH2CHOH]+ (g, anti) 778.9 767.6 ± 1.3 kJ/mol 44.0520 ± 0.0017 57239-63-1*2 Oxiranyl CH2(CHO) (g) 172.5 164.2 ± 1.4 kJ/mol 43.0446 ± 0.0016 31586-84-2*0 Oxiranylium [CH2(CHO)]+ (g, singlet) 901.1 893.2 ± 1.5 kJ/mol 43.0441 ± 0.0016 57789-76-1*2 C=O=C COC (g, triplet) 653.0 657.3 ± 1.6 kJ/mol 40.0208 ± 0.0016 *12071-23-7*1 C=O=C COC (g, singlet) 721.9 726.2 ± 1.6 kJ/mol 40.0208 ± 0.0016 *12071-23-7*2 Oxoethylidene HCC(O)H (g, singlet) 275.5 272.7 ± 1.9 kJ/mol 42.0367 ± 0.0016 39920-84-8*2 Formic acid cation [HC(O)OH]+ (g, syn) 721.87 714.78 ± 0.26 kJ/mol 46.0248 ± 0.0010 50614-05-6*1 Formyloxidanyl HC(O)O (g, 2B2) -122.06 -125.40 ± 0.56 kJ/mol 45.0174 ± 0.0010 16499-21-1*2 Oxygen atom O (g, triplet) 246.844 249.229 ± 0.0021 kJ/mol 15.99940 ± 0.00030 17778-80-2*1 1-Propanol CH3CH2CH2OH (g) -231.42 -255.26 ± 0.25 kJ/mol 60.0950 ± 0.0025 71-23-8*0 Fulminic acid HCNO (g) 170.81 169.35 ± 0.49 kJ/mol 43.02478 ± 0.00086 51060-05-0*0 (Formyloxy)methyl HC(O)OCH2 (g, anti) -136.3 -144.5 ± 1.3 kJ/mol 59.0440 ± 0.0017 3122-12-1*2 Carboxymethyl CH2C(O)OH (g, anti) -206.7 -216.0 ± 1.3 kJ/mol 59.0440 ± 0.0017 2887-46-9*2 Hydrogen chloride HCl (aq, 100 H2O) -165.757 ± 0.025 kJ/mol 36.46064 ± 0.00090 7647-01-0*828 Oxoniumyl ion [H2O]+ (g) 978.466 975.563 ± 0.028 kJ/mol 18.01473 ± 0.00033 56583-62-1*0 Dimethylamide [(CH3)2N]- (g) 122.2 103.8 ± 1.7 kJ/mol 44.0763 ± 0.0017 34285-60-4*0 Dinitrogen pentoxide O2NONO2 (g) 24.42 14.85 ± 0.35 kJ/mol 108.0105 ± 0.0015 10102-03-1*0 Hydrogen fluoride HF (aq, 30 H2O) -321.10 ± 0.16 kJ/mol 20.006343 ± 0.000070 7664-39-3*820 1,1,2-Trichloroethane CH2ClCHCl2 (g) -136.6 -148.3 ± 1.4 kJ/mol 133.4033 ± 0.0031 79-00-5*0 1,1,1,2-Tetrachloroethane CH2ClCCl3 (g) -144.6 -153.1 ± 1.3 kJ/mol 167.8481 ± 0.0039 630-20-6*0 Pentachloroethyl CCl3CCl2 (g) 26.9 25.1 ± 1.3 kJ/mol 201.2849 ± 0.0048 7094-17-9*0 Bromide Br- (aq) -120.93 ± 0.15 kJ/mol 79.90455 ± 0.00100 24959-67-9*800 Iodomethane CH3I (l) -12.18 ± 0.20 kJ/mol 141.93899 ± 0.00083 74-88-4*590 Difluoromethylene CF2 (g, triplet) 43.28 44.00 ± 0.38 kJ/mol 50.00751 ± 0.00080 2154-59-8*1 Trioxidanylium [HOOO]+ (g, trans) 1070.4 1064.1 ± 1.4 kJ/mol 49.00559 ± 0.00090 74241-49-9*1 Ethyl iodide CH3CH2I (l) -9.41 -39.28 ± 0.49 kJ/mol 155.9656 ± 0.0016 75-03-6*500 cis-1,2-Difluoroethene CHFCHF (g, cis) -302.90 -309.66 ± 0.90 kJ/mol 64.0341 ± 0.0016 1630-77-9*0 Fluoroethynyl CCF (g) 445.2 449.8 ± 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) -97.98 -113.92 ± 0.37 kJ/mol 187.8181 ± 0.0022 593-95-3*0 Benzene C6H6 (cr,l) 50.71 49.16 ± 0.23 kJ/mol 78.1118 ± 0.0048 71-43-2*500 o-Benzyne C6H4 (g) 467.91 458.99 ± 0.88 kJ/mol 76.0960 ± 0.0048 462-80-6*0 m-Benzyne C6H4 (g, singlet) 526.8 518.4 ± 1.2 kJ/mol 76.0960 ± 0.0048 1828-89-3*2 p-Benzyne C6H4 (g, singlet) 586.9 577.4 ± 1.2 kJ/mol 76.0960 ± 0.0048 3355-34-8*2 Cycloheptane CH2(CH2CH2CH2CH2CH2C (g) -72.78 -118.28 ± 0.53 kJ/mol 98.1861 ± 0.0057 291-64-5*0 Phenoxy C6H5O (g) 71.09 55.80 ± 0.88 kJ/mol 93.1033 ± 0.0048 2122-46-5*0 Benzoyl fluoride C6H5C(O)F (g) -288.1 -304.5 ± 1.5 kJ/mol 124.1124 ± 0.0056 455-32-3*0 Azide [NNN]- (g) 193.51 190.00 ± 0.91 kJ/mol 42.02077 ± 0.00021 14343-69-2*0 2-Cyclopropen-1-one OC(CHCH) (g) 163.7 159.8 ± 1.2 kJ/mol 54.0474 ± 0.0024 2961-80-0*0 Cyanovinylidene CCHCN (g) 581.6 584.1 ± 1.3 kJ/mol 51.0468 ± 0.0024 70277-81-5*0 Isocyanovinylidene CCHNC (g) 697.0 700.3 ± 1.4 kJ/mol 51.0468 ± 0.0024 737788-76-0*0 Isocyanoethene CH2CHNC (g, singlet) 285.04 278.53 ± 0.97 kJ/mol 53.0627 ± 0.0024 14668-82-7*1 1-Cyanoethylidene CH3CCN (g, triplet) 437.6 433.9 ± 1.5 kJ/mol 53.0627 ± 0.0024 498544-34-6*1 1H-Triazirin-1-yl N(NN) (g) 585.9 584.1 ± 2.0 kJ/mol 42.02022 ± 0.00021 912535-95-6*0 Isocyanomethylene HCNC (g, singlet) 582.3 583.6 ± 1.7 kJ/mol 39.0361 ± 0.0016 78694-65-2*1 Dioxiranylidene C(OO) (g) 190.3 191.1 ± 1.4 kJ/mol 44.00950 ± 0.00100 138832-57-2*0 2-Hydrotrioxy anion [OO(H)O]- (g) 27.5 21.8 ± 1.4 kJ/mol 49.00669 ± 0.00090 *89965-38-8*0 Methylidyne CH (g, doublet) 592.820 596.154 ± 0.099 kJ/mol 13.01864 ± 0.00080 3315-37-5*1 Triiodide [I3]- (aq) -51.27 ± 0.80 kJ/mol 380.713959 ± 0.000090 14900-04-0*800 Hydrogen difluoride cation [FFH]+ (g) 1174.3 1171.3 ± 1.5 kJ/mol 39.004198 ± 0.000070 *126950-54-7*0 Chlorine fluoride cation [ClF]+ (g) 1165.52 1165.71 ± 0.49 kJ/mol 54.45055 ± 0.00090 12432-44-9*0 Oxygen cation monohydrate [(HOH)O]+ (g) 1153.3 1147.8 ± 3.3 kJ/mol 34.01413 ± 0.00062 *31748-17-1*0 (E)-Diazene cation [HNNH]+ (g, trans) 1132.46 1125.53 ± 0.66 kJ/mol 30.02881 ± 0.00020 59952-06-6*0 Methylammonium [CH3NH3]+ (g) 628.4 609.5 ± 1.4 kJ/mol 32.06453 ± 0.00091 17000-00-9*0 Aminomethylene CHNH2 (g) 246.0 238.2 ± 1.5 kJ/mol 29.04126 ± 0.00083 35430-17-2*0 Methyleneamidogen anion [CH2N]- (g) 192.71 188.96 ± 0.96 kJ/mol 28.03387 ± 0.00082 28892-56-0*0 (Z)-Iminomethyl HCNH (g, cis) 294.49 291.01 ± 0.91 kJ/mol 28.03332 ± 0.00082 54980-11-9*0 Aminomethylidyne CNH2 (g) 371.9 368.3 ± 1.1 kJ/mol 28.03332 ± 0.00082 84654-89-7*0 Fluorohydrochlorine cation [FClH]+ (g) 975.3 972.3 ± 2.0 kJ/mol 55.45849 ± 0.00090 70110-64-4*0 Oxywater (H2O)O (g) 64.8 58.3 ± 1.3 kJ/mol 34.01468 ± 0.00062 171363-09-0*0 Oxygen anion monohydrate [(HOH)O]- (g) -239.0 -244.3 ± 3.0 kJ/mol 34.01523 ± 0.00062 31748-17-1*0 (Z)-Diazene HNNH (g, cis) 228.81 221.68 ± 0.64 kJ/mol 30.02936 ± 0.00020 15626-42-3*0 Deuterium atom D (g) 219.804 221.717 ± 0.000 kJ/mol 2.01410177800 ± 0.00000000040 16873-17-9*0 Methyleneoxonium CH2OH2 (g) 152.45 144.13 ± 0.49 kJ/mol 32.04186 ± 0.00090 177788-17-9*0 2-Hydrotrioxy cation [OO(H)O]+ (g) 1298.2 1291.5 ± 1.5 kJ/mol 49.00559 ± 0.00090 *74241-49-9*0 Hydroxymethylene anion [HCOH]- (g, trans) 147.1 144.1 ± 1.6 kJ/mol 30.02653 ± 0.00087 207914-87-2*1 Hydroxymethyliumylidene [COH]+ (g) 986.02 987.66 ± 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 Peroxyformic acid HC(O)OOH (g, trans) -265.3 -273.2 ± 1.6 kJ/mol 62.0248 ± 0.0012 107-32-4*2 Hydroxyoxomethoxy HOC(O)O (g) -358.8 -365.0 ± 1.5 kJ/mol 61.0168 ± 0.0012 38330-85-7*0 Hydroperoxycarbonyl HOOCO (g) -72.9 -76.7 ± 1.7 kJ/mol 61.0168 ± 0.0012 153751-35-0*0 Propan-1-yl-3-ylidene CH2CH2CH (g, quartet) 554.3 545.6 ± 1.4 kJ/mol 41.0718 ± 0.0024 *50457-59-5*2 Cycloprop-2-enyl CH(CHCH) (g) 490.23 485.68 ± 0.64 kJ/mol 39.0559 ± 0.0024 28933-84-8*0 Cyclopropenylidene C(CHCH) (g) 497.05 496.09 ± 0.46 kJ/mol 38.0480 ± 0.0024 16165-40-5*0 2-Propynylidyne anion [CCCH]- (g) 540.00 544.78 ± 0.84 kJ/mol 37.0406 ± 0.0024 82893-67-2*0 Cyclopropynyl CH(CC) (g) 710.9 715.0 ± 1.1 kJ/mol 37.0400 ± 0.0024 119178-99-3*0 Dihydrogen fluoride anion [HFH]- (g, triplet) 133.2 131.9 ± 1.6 kJ/mol 21.01483 ± 0.00014 117339-92-1*1 t-Butylium [(CH3)3C]+ (g) 733.86 710.58 ± 0.98 kJ/mol 57.1137 ± 0.0033 14804-25-2*0 t-Butyl anion [(CH3)3C]- (g) 76.4 51.6 ± 1.5 kJ/mol 57.1148 ± 0.0033 65114-21-8*0 iso-Butyl (CH3)2CHCH2 (g) 97.17 73.18 ± 0.76 kJ/mol 57.1143 ± 0.0033 4630-45-9*0 Bifluoride [FFH]- (g, triplet) -68.0 -67.6 ± 1.6 kJ/mol 39.005295 ± 0.000070 *18130-74-0*1 Methylcyclopropane CH3CH(CH2CH2) (g) 47.7 24.5 ± 1.3 kJ/mol 56.1063 ± 0.0032 594-11-6*0 Peroxychlorous acid HOOClO (g, syn) 96.2 90.2 ± 2.1 kJ/mol 84.4588 ± 0.0013 177778-92-6*1 Chlorine difluoride cation [FClF]+ (g) 998.9 996.7 ± 1.7 kJ/mol 73.44896 ± 0.00090 32629-46-2*0 Hydroxyaminiumyl [NOH]+ (g) 1161.2 1158.3 ± 1.4 kJ/mol 31.01353 ± 0.00032 63559-88-6*0 Ethanol CH3CH2OH (l) -269.73 -277.49 ± 0.23 kJ/mol 46.0684 ± 0.0017 64-17-5*500 2-Hydroxyethyl CH2CH2OH (g, staggered-anti) -5.5 -17.9 ± 1.3 kJ/mol 45.0605 ± 0.0017 4422-54-2*3 Vinyl alcohol cation [CH2CHOH]+ (g, syn) 787.03 775.80 ± 0.90 kJ/mol 44.0520 ± 0.0017 57239-63-1*1 Vinoxy CH2CHO (g) 22.62 15.78 ± 0.86 kJ/mol 43.0446 ± 0.0016 6912-06-7*0 Vinoxy cation [CH2CHO]+ (g, triplet) 1020.1 1013.0 ± 1.5 kJ/mol 43.0441 ± 0.0016 *35731-40-9*1 Vinoxide [CH2CHO]- (g) -153.38 -160.43 ± 0.86 kJ/mol 43.0452 ± 0.0016 35731-40-9*0 Oxiranyl anion [CH2(CHO)]- (g, singlet) 121.1 113.1 ± 1.6 kJ/mol 43.0452 ± 0.0016 72722-59-9*2 Acetic acid CH3C(O)OH (aq) -485.18 ± 0.23 kJ/mol 60.0520 ± 0.0017 64-19-7*800 COC vdW (CO)(C) (g, triplet) 589.7 598.5 ± 1.6 kJ/mol 40.0208 ± 0.0016 *12071-24-8*1 Oxirene O(CHCH) (g, c-triplet) 389.9 385.7 ± 1.4 kJ/mol 42.0367 ± 0.0016 157-18-6*12 Nitrosodioxaziridine ONN(OO) (g, trans) 413.6 407.6 ± 1.8 kJ/mol 76.01168 ± 0.00091 132871-99-9*1 Hydroxyamidogen HNOH (g, cis) 123.5 116.9 ± 1.7 kJ/mol 32.02202 ± 0.00034 13940-32-4*2 Hydroxyaminylium [HNOH]+ (g, trans) 1019.6 1012.4 ± 2.5 kJ/mol 32.02147 ± 0.00034 66097-71-0*1 Formyloxoniumylidene [HC(O)O]+ (g) 1017.4 1013.9 ± 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 Perchloric acid HOCl(O)(O)O (g) 13.2 1.8 ± 1.8 kJ/mol 100.4582 ± 0.0015 7601-90-3*0 2-Propanol CH3CH(OH)CH3 (g) -249.39 -273.49 ± 0.36 kJ/mol 60.0950 ± 0.0025 67-63-0*0 Dinitrogen tetraoxide O2NNO2 (g) 20.15 10.86 ± 0.14 kJ/mol 92.0111 ± 0.0012 10544-72-6*0 Cyanate [NCO]- (g) -221.23 -221.45 ± 0.53 kJ/mol 42.01739 ± 0.00086 661-20-1*0 Nitrosomethylidyne CNO (g) 388.8 390.2 ± 1.4 kJ/mol 42.01684 ± 0.00086 82267-15-0*0 Oxazirinyl C(NO) (g) 449.9 450.7 ± 1.5 kJ/mol 42.01684 ± 0.00086 228850-18-8*0 Oxofluoronium [FO]+ (g) 1342.64 1342.60 ± 0.81 kJ/mol 34.99725 ± 0.00030 12763-67-6*0 Propionic acid CH3CH2C(O)OH (g, syn) -436.41 -454.31 ± 0.60 kJ/mol 74.0785 ± 0.0025 79-09-4*1 2-Methoxy-2-oxoethyl CH2C(O)OCH3 (g, syn) -203.4 -218.6 ± 1.6 kJ/mol 73.0706 ± 0.0025 54668-31-4*1 (Acetyloxy)methyl CH3C(O)OCH2 (g, syn) -200.7 -214.5 ± 1.6 kJ/mol 73.0706 ± 0.0025 2887-49-2*1 Dimethylmethyleneammonium [(CH3)2NCH2]+ (g) 696.3 671.2 ± 1.4 kJ/mol 58.1018 ± 0.0025 28149-27-1*0 Trichloromethide [CCl3]- (g) -124.9 -124.3 ± 2.0 kJ/mol 118.3693 ± 0.0028 14478-07-0*0 Aquachlorine cation [ClOH2]+ (g) 821.8 815.0 ± 1.7 kJ/mol 53.46743 ± 0.00096 142599-65-3*0 Hydrogen fluoride HF (aq, 40 H2O) -321.13 ± 0.16 kJ/mol 20.006343 ± 0.000070 7664-39-3*821 1,1,2,2-Tetrachloroethane CHCl2CHCl2 (g) -146.9 -156.3 ± 1.5 kJ/mol 167.8481 ± 0.0039 79-34-5*0 1,1,2,2-Tetrachloroethane CHCl2CHCl2 (cr,l) -173.1 -202.0 ± 1.5 kJ/mol 167.8481 ± 0.0039 79-34-5*500 Pentachloroethane CHCl2CCl3 (cr,l) -202.9 ± 2.5 kJ/mol 202.2928 ± 0.0048 76-01-7*500 Trichloroethene CHClCCl2 (l) -49.3 ± 1.5 kJ/mol 131.3874 ± 0.0031 79-01-6*590 Tetrachloroethene CCl2CCl2 (l) -62.9 ± 1.1 kJ/mol 165.8322 ± 0.0039 127-18-4*500 Trichloroethene CHClCCl2 (g) -11.4 -14.7 ± 1.5 kJ/mol 131.3874 ± 0.0031 79-01-6*0 Bromodichloromethane CHCl2Br (g) -37.5 -49.3 ± 1.2 kJ/mol 163.8280 ± 0.0022 75-27-4*0 Difluorodibromomethane CF2Br2 (g) -364.3 -382.3 ± 1.3 kJ/mol 209.8155 ± 0.0022 75-61-6*0 Dichlorodibromomethane CCl2Br2 (g) 20.8 4.9 ± 1.3 kJ/mol 242.7241 ± 0.0028 594-18-3*0 Difluorobromomethane CHF2Br (g) -410.76 -423.95 ± 0.47 kJ/mol 130.9194 ± 0.0013 1511-62-2*0 Chlorosyl hydride HClO (g) 141.9 139.1 ± 1.7 kJ/mol 52.46004 ± 0.00095 71572-35-5*0 1,2-Difluoroethane CH2FCH2F (g) -434.39 -447.81 ± 0.82 kJ/mol 66.0500 ± 0.0016 624-72-6*0 Fluoro(fluorooxy)methylene FCOF (g, trans) -37.5 -39.1 ± 1.4 kJ/mol 66.00691 ± 0.00085 479587-30-9*1 Chlorine chlorite ClOClO (g, gauche) 168.6 166.2 ± 1.3 kJ/mol 102.9042 ± 0.0019 105206-44-8*3 Dioxyamidogen HNOO (g, cis) 240.4 233.8 ± 1.8 kJ/mol 47.01348 ± 0.00061 71843-95-3*2 Phenylium [C6H5]+ (g, triplet) 1250.6 1237.6 ± 1.6 kJ/mol 77.1034 ± 0.0048 17333-73-2*1 Chlorobenzene cation [C6H5Cl]+ (g) 942.47 928.54 ± 0.61 kJ/mol 112.5561 ± 0.0049 55450-32-3*0 Chlorobenzene C6H5Cl (cr,l) 11.22 ± 0.59 kJ/mol 112.5566 ± 0.0049 108-90-7*500 m-Chlorophenyl C6H4Cl (g) 319.9 309.1 ± 1.6 kJ/mol 111.5487 ± 0.0049 3474-40-6*0 p-Chlorophenyl C6H4Cl (g) 322.8 312.0 ± 1.6 kJ/mol 111.5487 ± 0.0049 2396-00-1*0 o-Chlorophenyl C6H4Cl (g) 327.1 316.4 ± 1.6 kJ/mol 111.5487 ± 0.0049 3474-42-8*0 Bromobenzene cation [C6H5Br]+ (g) 994.8 973.2 ± 1.3 kJ/mol 157.0074 ± 0.0049 55450-33-4*0 Iodobenzene C6H5I (cr,l) 112.8 112.9 ± 1.1 kJ/mol 204.0084 ± 0.0048 591-50-4*500 Nitrobenzene C6H5N(O)O (g) 81.4 61.4 ± 1.4 kJ/mol 123.1094 ± 0.0049 98-95-3*0 Methyl nitrite CH3ONO (g) -55.65 -66.32 ± 0.46 kJ/mol 61.0401 ± 0.0010 624-91-9*0 1,3-Butadien-2-ol CH2C(OH)CHCH2 (g, s-trans, syn) -53.8 -70.7 ± 1.6 kJ/mol 70.0898 ± 0.0032 59120-04-6*11 Formaldonitrone CH2NHO (g) 78.6 67.3 ± 1.5 kJ/mol 45.04066 ± 0.00088 67353-84-8*0 Trioxidaniumyl [HOOOH]+ (g, t, t) 925.4 916.2 ± 1.5 kJ/mol 50.01353 ± 0.00091 161321-37-5*2 2-Cyclopropen-1-imine (CHCH)CNH (g) 401.9 394.1 ± 1.4 kJ/mol 53.0627 ± 0.0024 31589-17-0*0 Peroxynitrous acid HOONO (g, cis, perp) -0.19 -7.24 ± 0.53 kJ/mol 63.01288 ± 0.00091 14691-52-2*2 1-Isocyanovinyl CH2CNC (g) 519.4 517.6 ± 1.5 kJ/mol 52.0547 ± 0.0024 321850-14-0*0 Fluorochlorate [ClF]- (g) -256.03 -255.42 ± 0.81 kJ/mol 54.45165 ± 0.00090 12272-56-9*0 Peroxyimidogen NOO (g) 405.4 403.4 ± 1.9 kJ/mol 46.00554 ± 0.00060 *60488-31-5*0 Hydrogen fluoride HF (aq, 35 H2O) -321.12 ± 0.16 kJ/mol 20.006343 ± 0.000070 7664-39-3*904 Peroxychlorite [OClOO]- (g) -34.3 -34.3 ± 2.0 kJ/mol 83.4514 ± 0.0013 852472-63-0*0 Bromo hypobromite BrOBr (g) 120.3 103.8 ± 1.2 kJ/mol 175.8074 ± 0.0020 21308-80-5*0 Iminomethyl anion [HCNH]- (g, trans) 237.4 233.5 ± 1.8 kJ/mol 28.03387 ± 0.00082 90623-30-6*1 Nitronium [ONO]+ (g) 961.78 958.22 ± 0.20 kJ/mol 46.00499 ± 0.00060 14522-82-8*0 1-Chloro ozone ClOOO (g, cis vdW) 226.3 223.1 ± 2.3 kJ/mol 83.4509 ± 0.0013 141801-66-3*101 Trihydrogen dioxide anion [HOHOH]- (g) -487.5 -495.8 ± 1.1 kJ/mol 35.02317 ± 0.00064 12501-19-8*0 Cyanogen iodide anion [ICN]- (g) 86.5 88.9 ± 8.1 kJ/mol 152.92246 ± 0.00080 1356929-44-6*0 Methanol CH3OH (l) -235.28 -238.62 ± 0.16 kJ/mol 32.04186 ± 0.00090 67-56-1*500 Oxadiazirene O(NN) (g) 351.7 349.9 ± 1.7 kJ/mol 44.01288 ± 0.00033 227934-45-4*0 Formaldehyde cation [CH2O]+ (g) 944.865 941.244 ± 0.098 kJ/mol 30.02543 ± 0.00087 54288-05-0*0 Isoformyl anion [COH]- (g, triplet) 267.4 268.0 ± 1.6 kJ/mol 29.01859 ± 0.00086 81747-63-9*2 Chlorohydrofluorine cation [ClFH]+ (g) 1000.8 998.1 ± 2.1 kJ/mol 55.45849 ± 0.00090 70110-63-3*0 NON NON (g) 545.5 542.6 ± 1.7 kJ/mol 44.01288 ± 0.00033 227934-46-5*0 Trifluoromethide [CF3]- (g) -637.6 -639.4 ± 1.8 kJ/mol 69.00646 ± 0.00080 54128-17-5*0 Dioxymethylidyne COO (g) 299.8 301.1 ± 1.7 kJ/mol 44.00950 ± 0.00100 791121-04-5*0 Diiodide [I2]- (g) -178.13 -180.72 ± 0.48 kJ/mol 253.809489 ± 0.000060 12190-71-5*0 Diazenide [NNH]- (g, vdW) 175.6 176.7 ± 1.6 kJ/mol 29.02197 ± 0.00016 71004-29-0*100 1-Propynyl CH3CC (g) 527.83 525.66 ± 0.98 kJ/mol 39.0559 ± 0.0024 89342-91-6*0 Cycloprop-2-enylium [CH(CHCH)]+ (g) 1080.4 1075.3 ± 1.2 kJ/mol 39.0554 ± 0.0024 26810-74-2*0 2-Propen-1-yl-3-ylidene CH2CHC (g) 556.7 554.4 ± 1.3 kJ/mol 39.0559 ± 0.0024 202744-74-9*0 2-Cyclopropen-1-ylium-1-yl [C(CHCH)]+ (g) 1382.0 1380.9 ± 1.1 kJ/mol 38.0474 ± 0.0024 85398-75-0*0 Propynylidene HCCCH (g, cis singlet) 597.6 599.3 ± 1.3 kJ/mol 38.0480 ± 0.0024 67152-18-5*3 Propenediylidene CHCHC (g) 796.1 797.3 ± 1.4 kJ/mol 38.0480 ± 0.0024 60731-11-5*0 Iodine I (g, 2P3/2) 107.157 106.757 ± 0.0021 kJ/mol 126.904470 ± 0.000030 14362-44-8*1 n-Butylium [CH3CH2CH2CH2]+ (g) 827.4 803.1 ± 1.2 kJ/mol 57.1137 ± 0.0033 25453-90-1*0 Carbide [C2]- (g) 504.69 511.27 ± 0.39 kJ/mol 24.0219 ± 0.0016 12595-78-7*0 Dioxygenyl ion monohydrate [(H2O)(O2)]+ (g) 828.5 821.4 ± 2.1 kJ/mol 50.01353 ± 0.00091 11083-61-7*0 iso-Hexane CH3CH2CH2CH(CH3)2 (g) -134.66 -173.92 ± 0.84 kJ/mol 86.1754 ± 0.0049 107-83-5*0 Ethyloxoniumyl [CH3CH2OH]+ (g) 783.3 766.3 ± 1.7 kJ/mol 46.0679 ± 0.0017 34480-55-2*0 1-Hydroxyethylium [CH3CHOH]+ (g) 608.75 594.32 ± 0.39 kJ/mol 45.0600 ± 0.0017 18682-96-7*0 2-Hydroxyethylium [CH2CH2OH]+ (g, staggered-anti) 1019.0 1006.2 ± 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 Acetaldehyde cation [CH3CHO]+ (g) 831.87 821.89 ± 0.26 kJ/mol 44.0520 ± 0.0017 36505-03-0*0 2-Cyclopropyn-1-ylidene C(CC) (g, triplet) 898.9 905.8 ± 1.6 kJ/mol 36.0321 ± 0.0024 102508-15-6*1 2-Cyclopropyn-1-ylium-1-yl [C(CC)]+ (g) 1944.7 1952.6 ± 1.9 kJ/mol 36.0316 ± 0.0024 154702-35-9*0 Oxiranylium [CH2(CHO)]+ (g, triplet) 1233.4 1226.4 ± 1.7 kJ/mol 43.0441 ± 0.0016 57789-76-1*1 Oxiranyl anion [CH2(CHO)]- (g, triplet) 140.8 134.8 ± 1.6 kJ/mol 43.0452 ± 0.0016 72722-59-9*1 Ketene CH2CO (g, singlet) -45.35 -48.47 ± 0.12 kJ/mol 42.0367 ± 0.0016 463-51-4*2 Ketenyl anion [HCCO]- (g) -48.47 -47.55 ± 0.84 kJ/mol 41.0293 ± 0.0016 64066-01-9*0 Dicarbon monoxide anion [CCO]- (g) 154.18 157.83 ± 0.98 kJ/mol 40.0213 ± 0.0016 87191-88-6*0 Dicarbon monoxide CCO (g, singlet) 440.22 444.56 ± 0.98 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 ± 1.8 kJ/mol 40.0213 ± 0.0016 *87191-88-6*0 Oxirene cation [O(CHCH)]+ (g) 1106.3 1102.6 ± 1.9 kJ/mol 42.0361 ± 0.0016 94664-69-4*0 Ethynol HCCOH (g, gauche triplet) 400.1 397.7 ± 2.0 kJ/mol 42.0367 ± 0.0016 32038-79-2*11 Oxoethylidene HCC(O)H (g, anti-triplet) 266.0 262.7 ± 1.9 kJ/mol 42.0367 ± 0.0016 39920-84-8*11 Hydroperoxymethyl CH2OOH (g) 72.9 65.6 ± 1.4 kJ/mol 47.0333 ± 0.0010 74087-87-9*0 Formic acid cation [HC(O)OH]+ (g, anti) 723.7 716.7 ± 1.2 kJ/mol 46.0248 ± 0.0010 50614-05-6*2 Formic acid anion [HC(O)OH]- (g, syn) -256.2 -262.4 ± 1.8 kJ/mol 46.0259 ± 0.0010 19066-82-1*1 Triiodide [I3]- (g) -254.3 -257.5 ± 3.4 kJ/mol 380.713959 ± 0.000090 14900-04-0*0 Isocyanic acid cation [HNCO]+ (g) 1002.94 1000.27 ± 0.50 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 Acetic acid CH3C(O)OH (aq, 1500 H2O) -484.92 ± 0.23 kJ/mol 60.0520 ± 0.0017 64-19-7*840 Acetyl chloride CH3C(O)Cl (l) -272.16 ± 0.33 kJ/mol 78.4973 ± 0.0019 75-36-5*500 Methyl formate HC(O)OCH3 (l) -388.48 ± 0.86 kJ/mol 60.0520 ± 0.0017 107-31-3*500 Ethyl formate HC(O)OCH2CH3 (g, anti) -355.5 -374.6 ± 1.4 kJ/mol 74.0785 ± 0.0025 109-94-4*2 Fluoronium [HFH]+ (g) 774.11 771.17 ± 0.88 kJ/mol 21.01373 ± 0.00014 12206-67-6*0 2-Methoxy-2-oxoethyl CH2C(O)OCH3 (g, anti) -173.3 -188.5 ± 1.8 kJ/mol 73.0706 ± 0.0025 54668-31-4*2 (Acetyloxy)methyl CH3C(O)OCH2 (g, anti) -174.4 -187.4 ± 1.7 kJ/mol 73.0706 ± 0.0025 2887-49-2*2 Hydroxyimidogen NOH (g) 218.00 215.12 ± 0.89 kJ/mol 31.01408 ± 0.00032 35337-59-8*0 Hydroxyoxoethenyl HOCCO (g) 24.3 22.6 ± 1.9 kJ/mol 57.0281 ± 0.0017 702699-39-6*0 Oxalic acid (C(O)OH)2 (g) -720.9 -731.5 ± 1.3 kJ/mol 90.0349 ± 0.0020 144-62-7*0 Fluoronium [(HF)(H)]+ (g, triplet) 1490.1 1491.5 ± 1.9 kJ/mol 21.01373 ± 0.00014 12206-67-6*1 Nitrous acid HONO (g, cis) -71.39 -77.75 ± 0.26 kJ/mol 47.01348 ± 0.00061 7782-77-6*2 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 Dibromide [Br2]- (g) -199.2 -213.3 ± 2.0 kJ/mol 159.8085 ± 0.0020 12595-70-9*0 Tetrachloromethane CCl4 (l) -108.66 -128.07 ± 0.43 kJ/mol 153.8215 ± 0.0037 56-23-5*500 Hydrogen fluoride HF (aq, 22 H2O) -321.06 ± 0.16 kJ/mol 20.006343 ± 0.000070 7664-39-3*902 Dichloromethylene anion [CCl2]- (g) 75.63 77.91 ± 0.77 kJ/mol 82.9166 ± 0.0020 118364-73-1*0 Dichloromethylium [CHCl2]+ (g) 894.7 891.5 ± 1.2 kJ/mol 83.9235 ± 0.0020 56932-33-3*0 Dichloromethide [CHCl2]- (g) -40.9 -42.6 ± 2.0 kJ/mol 83.9246 ± 0.0020 32180-91-9*0 Chloromethylium [CH2Cl]+ (g) 962.3 958.4 ± 1.2 kJ/mol 49.4787 ± 0.0012 59000-00-9*0 Chloromethylene CHCl (g, triplet) 346.14 346.44 ± 0.89 kJ/mol 48.4713 ± 0.0012 2108-20-5*1 1,2-Dichloroethane CH2ClCH2Cl (cr,l) -165.73 ± 0.56 kJ/mol 98.9586 ± 0.0024 107-06-2*500 1,1-Dichloroethane CH3CHCl2 (cr,l) -163.88 ± 0.48 kJ/mol 98.9586 ± 0.0024 75-34-3*500 Hydrogen difluoride (F)(HF) (g, perp) -187.4 -187.1 ± 1.6 kJ/mol 39.004746 ± 0.000070 12528-21-1*2 Pentachloroethane CHCl2CCl3 (g) -151.3 -157.2 ± 1.9 kJ/mol 202.2928 ± 0.0048 76-01-7*0 Chlorosyl chloride ClClO (g) 134.5 133.2 ± 1.4 kJ/mol 86.9048 ± 0.0018 86825-56-1*0 Chloroform CHCl3 (l) -133.59 ± 0.51 kJ/mol 119.3767 ± 0.0028 67-66-3*590 Chlorodibromomethane CHClBr2 (g) 18.4 -0.4 ± 3.3 kJ/mol 208.2793 ± 0.0023 124-48-1*0 Tribromofluoromethane CBr3F (g) -105.9 -129.9 ± 1.5 kJ/mol 270.7211 ± 0.0031 353-54-8*0 Tribromochloromethane CBr3Cl (g) 77.3 54.4 ± 1.5 kJ/mol 287.1754 ± 0.0032 594-15-0*0 Azidonitrene NNNN (g, Cs) 692.1 687.5 ± 1.4 kJ/mol 56.02696 ± 0.00028 147363-92-6*2 Bromochloromethane CH2ClBr (g) -28.4 -42.4 ± 1.3 kJ/mol 129.3833 ± 0.0016 74-97-5*0 Fluoromethylene CHF (g) 148.38 148.66 ± 0.43 kJ/mol 32.01704 ± 0.00080 13453-52-6*0 Hydrogen fluoride HF (aq, 50 H2O) -321.16 ± 0.16 kJ/mol 20.006343 ± 0.000070 7664-39-3*822 Ethylene cation [CH2CH2]+ (g) 1075.18 1067.97 ± 0.12 kJ/mol 28.0526 ± 0.0016 34470-02-5*0 Ethyl iodide CH3CH2I (g) 8.70 -7.18 ± 0.49 kJ/mol 155.9656 ± 0.0016 75-03-6*0 1,2-Dibromoacetylene BrCCBr (g) 332.4 321.5 ± 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 Oxochloronium [ClO]+ (g) 1150.86 1150.69 ± 0.66 kJ/mol 51.45155 ± 0.00095 12301-79-0*0 Fluorooxomethylium [FCO]+ (g) 724.9 724.5 ± 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 Azanylium [NH2]+ (g) 1266.55 1264.48 ± 0.11 kJ/mol 16.02207 ± 0.00016 15194-15-7*0 Benzene cation [C6H6]+ (g) 992.50 976.03 ± 0.23 kJ/mol 78.1113 ± 0.0048 34504-50-2*0 Hydroxydioxonitrate [HON(O)O]- (g) -193.2 -197.6 ± 2.4 kJ/mol 63.01343 ± 0.00091 58875-09-5*0 Dihydrogen fluoride anion [(F)(HH)]- (g, singlet) -257.0 -260.1 ± 1.9 kJ/mol 21.01483 ± 0.00014 *117339-92-1*2 m-Chlorophenide [C6H4Cl]- (g) 172.1 161.9 ± 1.6 kJ/mol 111.5492 ± 0.0049 77748-34-6*0 p-Chlorophenide [C6H4Cl]- (g) 179.1 168.7 ± 1.5 kJ/mol 111.5492 ± 0.0049 77748-42-6*0 o-Chlorophenide [C6H4Cl]- (g) 158.2 148.3 ± 1.6 kJ/mol 111.5492 ± 0.0049 72863-53-7*0 Ammonia NH3 (aq, undissoc) -80.886 ± 0.053 kJ/mol 17.03056 ± 0.00022 7664-41-7*1000 2-Oxopropylium [CH3C(O)CH2]+ (g) 784.4 770.6 ± 1.8 kJ/mol 57.0707 ± 0.0024 54088-52-7*0 2,3-Butanedione CH3C(O)C(O)CH3 (g) -310.63 -327.19 ± 0.66 kJ/mol 86.0892 ± 0.0033 431-03-8*0 1,2-Dibromoethane CH2BrCH2Br (g) -11.7 -38.6 ± 1.2 kJ/mol 187.8612 ± 0.0026 106-93-4*0 2-Butanone CH3CH2C(O)CH3 (g) -216.96 -238.41 ± 0.91 kJ/mol 72.1057 ± 0.0033 78-93-3*0 Chlorite [OClO]- (g) -105.62 -107.79 ± 0.35 kJ/mol 67.4520 ± 0.0011 14998-27-7*0 2-Propynal CHCCHO (g) 135.5 133.3 ± 1.4 kJ/mol 54.0474 ± 0.0024 624-67-9*0 Dioxygen O2 (g, singlet) 94.410 94.383 ± 0.000 kJ/mol 31.99880 ± 0.00060 7782-44-7*2 Ammonium nitrate (NH4)NO3 (cr,l) -350.29 -365.26 ± 0.18 kJ/mol 80.04344 ± 0.00095 6484-52-2*500 Fluorosyl fluoride FFO (g, triplet) 192.6 193.1 ± 2.3 kJ/mol 53.99621 ± 0.00030 86825-57-2*1 Chloride Cl- (aq) -166.991 ± 0.023 kJ/mol 35.45325 ± 0.00090 16887-00-6*800 1-Isocyanoethylidene CH3CNC (g, triplet) 545.5 540.7 ± 1.6 kJ/mol 53.0627 ± 0.0024 *498544-34-6*1 3-Imino-2-propen-1-ylidene CHCHCNH (g, anti-triplet) 571.8 566.8 ± 1.6 kJ/mol 53.0627 ± 0.0024 916765-05-4*21 2-(Methylidyneamino)ethenyl CHCHNCH (g, anti-triplet) 634.4 629.7 ± 1.6 kJ/mol 53.0627 ± 0.0024 123416-74-0*21 Azete (CHCHCH)N (g) 469.5 461.3 ± 1.5 kJ/mol 53.0627 ± 0.0024 287-24-1*0 2-Cyanovinylium [CHCHCN]+ (g, anti triplet) 1517.1 1515.0 ± 1.8 kJ/mol 52.0542 ± 0.0024 85398-67-0*21 2-Cyanovinyl anion [CHCHCN]- (g, syn) 263.7 260.7 ± 1.8 kJ/mol 52.0553 ± 0.0024 *85398-67-0*2 2-Isocyanovinyl CHCHNC (g, anti) 543.1 541.1 ± 1.7 kJ/mol 52.0547 ± 0.0024 225798-14-1*1 3-Oxo-1,2-propadienylidene CCCO (g) 329.9 335.9 ± 2.0 kJ/mol 52.0315 ± 0.0024 11127-17-6*0 Hydroxymethylene anion [HCOH]- (g, cis) 160.2 157.5 ± 1.7 kJ/mol 30.02653 ± 0.00087 207914-87-2*2 Hydroxymethylene anion [HCOH]- (g, gauche quartet) 334.0 334.8 ± 2.1 kJ/mol 30.02653 ± 0.00087 207914-87-2*3 Oxadiazirine anion [O(NN)]- (g) 95.1 95.5 ± 2.9 kJ/mol 44.01343 ± 0.00033 350586-31-1*0 Aquacarbon H2OC (g, singlet vdW) 467.6 465.5 ± 1.9 kJ/mol 30.02598 ± 0.00087 81434-73-3*102 Aquacarbon cation [H2OC]+ (g) 1196.1 1193.0 ± 1.7 kJ/mol 30.02543 ± 0.00087 *81434-73-3*0 1-Hydrazinylium-1-yl [NNH2]+ (g) 1143.4 1136.4 ± 1.4 kJ/mol 30.02881 ± 0.00020 63986-30-1*0 Carbonic acid C(O)(OH)2 (g) -602.76 -612.07 ± 0.75 kJ/mol 62.0248 ± 0.0012 463-79-6*0 Peroxyformic acid HC(O)OOH (g, gauche) -265.2 -273.1 ± 1.5 kJ/mol 62.0248 ± 0.0012 107-32-4*3 Dioxaziridinyl anion [N(OO)]- (g) 295.9 293.4 ± 1.7 kJ/mol 46.00609 ± 0.00060 66252-31-1*0 Hydrogen chloride HCl (aq, 75 H2O) -165.556 ± 0.026 kJ/mol 36.46064 ± 0.00090 7647-01-0*825 1-Methylethylidene CH3CCH3 (g, triplet) 326.9 313.7 ± 1.6 kJ/mol 42.0797 ± 0.0024 40852-89-9*1 1-Chloro ozone anion [ClOOO]- (g, perp) -108.9 -111.4 ± 2.2 kJ/mol 83.4514 ± 0.0013 224299-15-4*3 Trioxodinitrate anion [ONN(O)O]- (g, vdW) -104.3 -107.5 ± 1.9 kJ/mol 76.01223 ± 0.00091 194856-62-7*100 Fluorosyl fluoride anion [FFO]- (g, doublet) -147.2 -146.9 ± 3.0 kJ/mol 53.99675 ± 0.00030 *86825-57-2*2 Dihydrogen fluoride (H)(HF) (g) -55.9 -54.9 ± 1.6 kJ/mol 21.01428 ± 0.00014 12592-22-2*1 Diazenide [NNH]- (g, triplet) 347.4 344.6 ± 1.6 kJ/mol 29.02197 ± 0.00016 71004-29-0*1 Propynylidene cation [HCCCH]+ (g) 1410.8 1413.4 ± 1.3 kJ/mol 38.0474 ± 0.0024 75123-91-0*0 Propynylidene HCCCH (g, trans singlet) 597.4 599.2 ± 1.1 kJ/mol 38.0480 ± 0.0024 67152-18-5*4 Propadienylidenide [CH2CC]- (g) 381.14 382.04 ± 0.42 kJ/mol 38.0485 ± 0.0024 109292-49-1*0 1,2-Propadien-1-ylium-1-yl [CH2CC]+ (g) 1561.6 1562.9 ± 1.4 kJ/mol 38.0474 ± 0.0024 110714-00-6*0 Ethynylene cation [C2]+ (g) 1965.16 1971.74 ± 0.50 kJ/mol 24.0209 ± 0.0016 12595-79-8*0 Methylimidogen CH3N (g) 323.2 315.5 ± 1.7 kJ/mol 29.04126 ± 0.00083 27770-42-9*0 1-Chloro ozone anion [ClOOO]- (g, cis) -66.8 -68.7 ± 2.1 kJ/mol 83.4514 ± 0.0013 224299-15-4*1 Hydrogen fluoride HF (l) -302.40 ± 0.16 kJ/mol 20.006343 ± 0.000070 7664-39-3*590 Hydroxylamine NH2OH (g, cis) -15.5 -26.0 ± 1.4 kJ/mol 33.02996 ± 0.00037 7803-49-8*2 Hydroxylamine cation [NH2OH]+ (g) 857.6 847.8 ± 1.6 kJ/mol 33.02941 ± 0.00037 62675-55-2*0 Hydrofluorate ion [HF]- (g) -75.6 -75.1 ± 1.8 kJ/mol 20.006892 ± 0.000070 37249-79-9*0 n-Pentane CH3CH2CH2CH2CH3 (cr,l) -156.05 -173.02 ± 0.31 kJ/mol 72.1488 ± 0.0041 109-66-0*500 iso-Pentane CH3CH2CH(CH3)2 (l) -178.44 ± 0.43 kJ/mol 72.1488 ± 0.0041 78-78-4*500 neo-Pentane C(CH3)4 (l) -189.90 ± 0.40 kJ/mol 72.1488 ± 0.0041 463-82-1*500 Cyclopentane CH2(CH2CH2CH2CH2) (l) -105.15 ± 0.40 kJ/mol 70.1329 ± 0.0041 287-92-3*590 1,5-Hexadiene CH2CHCH2CH2CHCH2 (g) 108.38 83.79 ± 0.40 kJ/mol 82.1436 ± 0.0049 592-42-7*0 Chlorine difluoride anion [FClF]- (g) -504.9 -505.8 ± 1.9 kJ/mol 73.45005 ± 0.00090 16892-05-0*0 Hydrogen fluoride HF (aq, 10 H2O) -320.88 ± 0.16 kJ/mol 20.006343 ± 0.000070 7664-39-3*815 Peroxyimidogen cation [NOO]+ (g) 1409.6 1406.8 ± 1.9 kJ/mol 46.00499 ± 0.00060 *60488-32-6*0 Perchloryloxy OCl(O)(O)O (g) 248.6 241.0 ± 1.8 kJ/mol 99.4503 ± 0.0015 12133-63-0*0 Ethoxy CH3CH2O (g) 1.30 -12.13 ± 0.47 kJ/mol 45.0605 ± 0.0017 2154-50-9*0 Nitrogen hydride oxide NH3O (g) 71.1 59.9 ± 1.5 kJ/mol 33.02996 ± 0.00037 38544-48-8*0 Peroxyimidogen anion [NOO]- (g) 165.0 162.7 ± 1.7 kJ/mol 46.00609 ± 0.00060 60488-31-5*0 Aminooxy cation [NH2O]+ (g) 946.05 938.92 ± 0.80 kJ/mol 32.02147 ± 0.00034 *51375-41-8*0 Nitrosyl fluoride FNO (g) -85.81 -88.18 ± 0.93 kJ/mol 49.00454 ± 0.00031 7789-25-5*0 Trioxidanyl HOOO (g, cis) 26.29 23.02 ± 0.19 kJ/mol 49.00614 ± 0.00090 12500-78-6*2 Acetylene anion [HCCH]- (g, trans ?) 356.8 356.7 ± 1.9 kJ/mol 26.0378 ± 0.0016 50443-89-5*1 Fluorodioxidenium [FOO]+ (g) 1221.9 1219.5 ± 2.0 kJ/mol 50.99665 ± 0.00060 139584-95-5*0 Iminomethyl anion [HCNH]- (g, cis) 252.6 248.9 ± 1.8 kJ/mol 28.03387 ± 0.00082 90623-30-6*2 Chlorine difluoride ClFF (g) 22.5 23.8 ± 1.9 kJ/mol 73.44951 ± 0.00090 91483-78-2*0 Dicarbon monoxide cation [CCO]+ (g) 1433.9 1439.0 ± 2.2 kJ/mol 40.0203 ± 0.0016 12287-08-0*0 Tetraoxidanyl (HO2)(O2) (g, vdW) 2.0 0.2 ± 3.0 kJ/mol 65.0055 ± 0.0012 69696-93-1*100 C=O-C cation [COC]+ (g, quartet) 1816.8 1820.9 ± 2.0 kJ/mol 40.0203 ± 0.0016 83483-98-1*2 Hydrogen cyanide cation [HCN]+ (g) 1442.52 1442.05 ± 0.20 kJ/mol 27.02483 ± 0.00081 12601-62-6*0 Oxirene anion [O(CHCH)]- (g) 288.3 285.3 ± 2.2 kJ/mol 42.0372 ± 0.0016 *157-18-6*0 Dihydrooxooxygen cation [(H2O)O]+ (g) 994.8 988.1 ± 1.6 kJ/mol 34.01413 ± 0.00062 177329-59-8*0 Oxoethylidene HCC(O)H (g, triplet) 261.2 258.3 ± 1.6 kJ/mol 42.0367 ± 0.0016 39920-84-8*1 Perchlorate [OCl(O)(O)O]- (g) -263.2 -272.1 ± 2.2 kJ/mol 99.4508 ± 0.0015 14797-73-0*0 Formic acid anion [HC(O)OH]- (g, anti) -241.2 -247.0 ± 1.9 kJ/mol 46.0259 ± 0.0010 19066-82-1*2 Fluorodioxidanide [FOO]- (g) -256.8 -256.1 ± 1.9 kJ/mol 50.99775 ± 0.00060 23553-17-5*0 Dioxirane cation [CH2(OO)]+ (g) 1050.8 1043.2 ± 2.0 kJ/mol 46.0248 ± 0.0010 232262-10-1*0 Dioxymethyl cation [CH2OO]+ (g) 1074.9 1068.6 ± 1.8 kJ/mol 46.0248 ± 0.0010 232262-11-2*0 Dioxofluorine OFO (g) 524.0 523.2 ± 1.1 kJ/mol 50.99720 ± 0.00060 175861-93-5*0 1,3-Butadiyne-1,4-diyl CCCC (g) 1052.46 1062.44 ± 0.68 kJ/mol 48.0428 ± 0.0032 78015-07-3*0 Hydroxyaminylium [HNOH]+ (g, cis) 1048.6 1041.4 ± 2.6 kJ/mol 32.02147 ± 0.00034 66097-71-0*2 Dioxymethylene HCOO (g, cis) 341.8 339.8 ± 3.0 kJ/mol 45.0174 ± 0.0010 438586-67-5*2 OH-CO vdW complex (OH)(CO) (g, vdW) -80.26 -76.54 ± 0.88 kJ/mol 45.0174 ± 0.0010 *2564-85-4*100 CO-HO vdW complex (CO)(HO) (g, vdW) -77.4 -73.2 ± 1.3 kJ/mol 45.0174 ± 0.0010 *2564-84-3*100 Hydroxyamidogen anion [HNOH]- (g) 90.8 84.9 ± 2.8 kJ/mol 32.02257 ± 0.00034 *66097-71-0*0 Cyanato cation [NCO]+ (g) 1261.45 1261.95 ± 0.58 kJ/mol 42.01629 ± 0.00086 17247-99-3*0 Nitrosomethyliumylidene [CNO]+ (g) 1509.6 1510.7 ± 1.7 kJ/mol 42.01629 ± 0.00086 67197-19-7*0 Fulminate [CNO]- (g) 59.4 59.6 ± 1.8 kJ/mol 42.01739 ± 0.00086 28269-67-2*0 Deuterium atom cation D+ (g) 1532.210 1534.123 ± 0.000 kJ/mol 2.01355319809 ± 0.00000000040 14464-47-2*0 Acetic acid CH3C(O)OH (l) -484.10 -483.68 ± 0.18 kJ/mol 60.0520 ± 0.0017 64-19-7*500 Acetic acid CH3C(O)OH (aq, 75 H2O) -484.71 ± 0.23 kJ/mol 60.0520 ± 0.0017 64-19-7*825 Acetic acid CH3C(O)OH (aq, 700 H2O) -484.90 ± 0.23 kJ/mol 60.0520 ± 0.0017 64-19-7*835 Hydrogen fluoride HF (aq, 18 H2O) -321.03 ± 0.16 kJ/mol 20.006343 ± 0.000070 7664-39-3*901 Glyoxal OCHCHO (g, cis) -189.28 -194.73 ± 0.75 kJ/mol 58.0361 ± 0.0017 107-22-2*2 Glyoxal OCHCHO (g) -207.73 -213.29 ± 0.61 kJ/mol 58.0361 ± 0.0017 107-22-2*0 Ethynediol HOCCOH (g) -18.2 -21.9 ± 1.9 kJ/mol 58.0361 ± 0.0017 16005-17-7*0 Nitrosyl nitrate ON(O2)NO (g, perp) 70.6 62.3 ± 1.8 kJ/mol 92.0111 ± 0.0012 *15969-55-8*0 Azidonitrene NNNN (g, C2h) 660.8 657.6 ± 1.6 kJ/mol 56.02696 ± 0.00028 147363-92-6*1 Dimethylaminylium [(CH3)2N]+ (g) 1040.1 1024.7 ± 1.8 kJ/mol 44.0752 ± 0.0017 49784-85-2*0 Nirous oxide cation [NNO]+ (g) 1329.67 1326.78 ± 0.12 kJ/mol 44.01233 ± 0.00033 12269-46-4*0 Diisocyanogen CNNC (g) 610.3 612.6 ± 1.8 kJ/mol 52.0349 ± 0.0016 78800-21-2*0 Dichloromethylene CCl2 (g, triplet) 313.63 314.83 ± 0.90 kJ/mol 82.9161 ± 0.0020 1605-72-7*1 Chloromethyliumyl [CHCl]+ (g) 1207.4 1207.6 ± 2.0 kJ/mol 48.4708 ± 0.0012 89877-51-0*0 Chloromethylene anion [CHCl]- (g) 203.44 204.25 ± 0.94 kJ/mol 48.4719 ± 0.0012 75466-08-9*0 Chlorohydroxymethyl CH(Cl)OH (g, anti-gauche) -46.2 -51.8 ± 2.0 kJ/mol 65.4787 ± 0.0012 147139-06-8*2 Dihydrogen cation [H2]+ (g) 1488.364 1488.480 ± 0.000 kJ/mol 2.01533 ± 0.00014 12184-90-6*0 Trioxidaniumyl [HOOOH]+ (g, c, t) 935.2 926.1 ± 1.6 kJ/mol 50.01353 ± 0.00091 161321-37-5*3 1,1,2-Trichloroethane CH2ClCHCl2 (l) -188.6 ± 1.4 kJ/mol 133.4033 ± 0.0031 79-00-5*500 Ethane cation [CH3CH3]+ (g) 1043.17 1029.17 ± 0.60 kJ/mol 30.0685 ± 0.0017 34488-65-8*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) -216.5 ± 2.8 kJ/mol 236.7376 ± 0.0056 67-72-1*500 Nitrous acid HONO (g) -73.008 -78.665 ± 0.078 kJ/mol 47.01348 ± 0.00061 7782-77-6*0 3-Chloro-3-methyl-3H-diazirine (NN)CClCH3 (g) 251.4 239.5 ± 2.7 kJ/mol 90.5114 ± 0.0019 4222-21-3*0 trans-1,2-Dichloroethene CHClCHCl (g, trans) 5.29 -0.13 ± 0.54 kJ/mol 96.9427 ± 0.0024 156-60-5*0 Hydrogen fluoride HF (aq, 60 H2O) -321.18 ± 0.16 kJ/mol 20.006343 ± 0.000070 7664-39-3*823 Fluorochlorobromomethane CHFClBr (g) -218.3 -230.9 ± 4.9 kJ/mol 147.3737 ± 0.0016 593-98-6*0 Bifluoride [FHF]- (g) -705.21 -709.06 ± 0.36 kJ/mol 39.005295 ± 0.000070 18130-74-0*0 Fluoromethyliumyl [CHF]+ (g) 1116.6 1116.9 ± 1.7 kJ/mol 32.01649 ± 0.00080 89877-52-1*0 Fluoromethylene anion [CHF]- (g) 95.92 96.46 ± 0.61 kJ/mol 32.01759 ± 0.00080 71267-42-0*0 Polytetrafluoroethylene CF2CF2 (s) -829.65 ± 0.58 kJ/mol 100.0150 ± 0.0016 9002-84-0*591 Trioxidanylium [HOOO]+ (g, cis) 1085.2 1078.9 ± 1.4 kJ/mol 49.00559 ± 0.00090 74241-49-9*2 trans-1,2-Difluoroethene CHFCHF (g, trans) -299.66 -306.10 ± 0.90 kJ/mol 64.0341 ± 0.0016 1630-78-0*0 (Z)-Diazene cation [HNNH]+ (g, cis) 1157.0 1150.1 ± 1.3 kJ/mol 30.02881 ± 0.00020 86631-37-0*0 Fluoroethynide [CCF]- (g) 133.3 137.5 ± 1.5 kJ/mol 43.0204 ± 0.0016 85905-56-2*0 Ethylene anion [CH2CH2]- (g, anti ?) 232.0 224.4 ± 2.0 kJ/mol 28.0537 ± 0.0016 34527-91-8*1 Formyl fluoride cation [CHFO]+ (g) 816.6 813.3 ± 1.3 kJ/mol 48.01589 ± 0.00086 99766-68-4*0 (E)-Diazene anion [HNNH]- (g, trans) 265.5 258.7 ± 2.0 kJ/mol 30.02991 ± 0.00020 *59952-06-6*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 Hydrogen chloride HCl (aq, 2000 H2O) -166.682 ± 0.024 kJ/mol 36.46064 ± 0.00090 7647-01-0*841 Hydrogen peroxide cation [H2O2]+ (g, cis) 930.98 924.12 ± 0.98 kJ/mol 34.01413 ± 0.00062 12325-10-9*2 Trifluoride ion [F3]- (g) -348.8 -349.7 ± 2.6 kJ/mol 56.9957582 ± 0.0000015 25730-99-8*0 Hydrogen bromide HBr (aq, 600 H2O) -120.44 ± 0.15 kJ/mol 80.9119 ± 0.0010 10035-10-6*834 o-Benzyne cation [C6H4]+ (g) 1393.8 1385.8 ± 1.7 kJ/mol 76.0954 ± 0.0048 70220-84-7*0 Aminyliumyl [NH]+ (g) 1659.03 1659.95 ± 0.24 kJ/mol 15.014131 ± 0.000099 19067-62-0*0 m-Benzyne cation [C6H4]+ (g) 1365.5 1356.9 ± 1.9 kJ/mol 76.0954 ± 0.0048 121058-08-0*0 p-Benzyne C6H4 (g, triplet) 603.4 594.0 ± 1.2 kJ/mol 76.0960 ± 0.0048 3355-34-8*1 Benzylium [C6H5CH2]+ (g) 929.35 909.85 ± 0.61 kJ/mol 91.1299 ± 0.0056 6711-19-9*0 1,3-Cycloheptadiene CH2(CHCHCHCHCH2CH2) (g, c-c) 123.27 94.16 ± 0.78 kJ/mol 94.1543 ± 0.0056 4054-38-0*1 Tropylium [CH(CHCHCHCHCHCH)]+ (g) 897.9 878.2 ± 1.1 kJ/mol 91.1299 ± 0.0056 26811-28-9*0 Nitric acid HON(O)O (aq, 1000 H2O) -206.32 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*839 Hydrogen bromide HBr (aq, 5000 H2O) -120.74 ± 0.15 kJ/mol 80.9119 ± 0.0010 10035-10-6*844 Acetone enol CH3C(OH)CH2 (g, anti) -147.1 -164.4 ± 1.3 kJ/mol 58.0791 ± 0.0025 29456-04-0*2 Methyleneoxonium cation [CH2OH2]+ (g) 827.7 818.3 ± 1.7 kJ/mol 32.04131 ± 0.00090 *177788-17-9*0 cis-1,2-Dibromoethene CHBrCHBr (g, cis) 120.9 100.4 ± 2.1 kJ/mol 185.8453 ± 0.0026 590-11-4*0 1,1-Dibromoethane CH3CHBr2 (g) -5.4 -32.4 ± 1.8 kJ/mol 187.8612 ± 0.0026 557-91-5*0 Krypton hydride cation [KrH]+ (g) 1106.33 1104.55 ± 0.69 kJ/mol 84.8074 ± 0.1000 37276-90-7*0 Hydroxymethanide [CH2OH]- (g) 9.4 2.8 ± 1.7 kJ/mol 31.03447 ± 0.00088 55830-71-2*0 Formaldehyde CH2O (g, singlet) -105.377 -109.215 ± 0.097 kJ/mol 30.02598 ± 0.00087 50-00-0*2 Fluoroniumyl ion [HF]+ (g) 1275.561 1275.793 ± 0.050 kJ/mol 20.005795 ± 0.000070 12381-92-9*0 Formaldoxime CH2NOH (g, cis) 50.8 40.0 ± 1.8 kJ/mol 45.04066 ± 0.00088 75-17-2*2 Oxaziridine CH2(NHO) (g) 115.8 104.1 ± 2.1 kJ/mol 45.04066 ± 0.00088 6827-26-5*0 Nitric acid HON(O)O (cr,l) -179.02 -173.29 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*500 Dihydrogen fluoride anion [(HF)(H)]- (g, singlet) -61.9 -60.5 ± 3.2 kJ/mol 21.01483 ± 0.00014 117339-92-1*2 Dioxaziridinyl cation [N(OO)]+ (g) 1365.9 1363.3 ± 1.7 kJ/mol 46.00499 ± 0.00060 *66252-29-7*0 Xenon cation Xe+ (g) 1170.354 1170.354 ± 0.0062 kJ/mol 131.2895 ± 0.0200 24203-25-6*0 2-Methylene-2H-azirine (CHN)CCH2 (g) 404.2 396.9 ± 1.7 kJ/mol 53.0627 ± 0.0024 110027-86-6*0 Chlorine oxide peroxide OClOO (g, vdW) 226.5 227.4 ± 2.5 kJ/mol 83.4509 ± 0.0013 141801-67-4*100 2-Cyanovinylium [CHCHCN]+ (g, syn triplet) 1517.3 1515.2 ± 1.8 kJ/mol 52.0542 ± 0.0024 85398-67-0*22 2-Cyanovinyl anion [CHCHCN]- (g, anti) 266.1 263.2 ± 1.8 kJ/mol 52.0553 ± 0.0024 *85398-67-0*1 Hydroxymethylene cation [HCOH]+ (g, cis) 986.3 982.7 ± 1.6 kJ/mol 30.02543 ± 0.00087 135395-06-1*2 Hydroxymethylene cation [HCOH]+ (g, gauche quartet) 1482.1 1479.4 ± 1.9 kJ/mol 30.02543 ± 0.00087 135395-06-1*3 2-Isocyanovinyl CHCHNC (g, syn) 544.5 542.6 ± 1.7 kJ/mol 52.0547 ± 0.0024 225798-14-1*2 Cyanomethylene HCCN (g, singlet) 529.5 530.5 ± 1.3 kJ/mol 39.0361 ± 0.0016 2612-62-6*2 Isocyanomethylene HCNC (g, triplet) 586.3 587.3 ± 1.7 kJ/mol 39.0361 ± 0.0016 78694-65-2*2 Dioxodiazoxane ONONO (g, t, c) 109.3 105.2 ± 1.8 kJ/mol 76.01168 ± 0.00091 122413-35-8*2 2-Chloro ozone anion [ClO(O)O]- (g) -103.4 -105.6 ± 3.2 kJ/mol 83.4514 ± 0.0013 *141801-67-4*0 Cyclopentene CH2(CH2CHCHCH2) (l) 4.40 ± 0.42 kJ/mol 68.1170 ± 0.0040 142-29-0*590 Fluorosyl fluoride anion [FFO]- (g, quartet) -56.6 -55.7 ± 2.4 kJ/mol 53.99675 ± 0.00030 *86825-57-2*1 n-Hexane CH3CH2CH2CH2CH2CH3 (cr,l) -179.98 -198.64 ± 0.34 kJ/mol 86.1754 ± 0.0049 110-54-3*500 Methylimidogen anion [CH3N]- (g) 321.3 313.6 ± 1.8 kJ/mol 29.04181 ± 0.00083 82539-34-2*0 1,2-Propadien-1-yl-3-ylidene anion [CCC]- (g) 622.0 629.4 ± 1.3 kJ/mol 36.0326 ± 0.0024 109292-47-9*0 1-Hydroxyethanide [CH3CHOH]- (g) -20.3 -33.7 ± 2.2 kJ/mol 45.0610 ± 0.0017 88032-18-2*0 Methyleneaminylium [CH2N]+ (g, triplet) 1456.6 1453.0 ± 2.2 kJ/mol 28.03277 ± 0.00082 53518-13-1*1 Acetaldehyde anion [CH3CHO]- (g) -62.3 -72.5 ± 2.2 kJ/mol 44.0531 ± 0.0017 60427-04-5*0 Peroxyhypochlorite [ClOO]- (g) -249.22 -248.20 ± 0.37 kJ/mol 67.4520 ± 0.0011 224299-14-3*0 2-Cyclopropyn-1-ylidene C(CC) (g, singlet) 993.2 1000.1 ± 2.5 kJ/mol 36.0321 ± 0.0024 102508-15-6*2 Ozone cation [OOO]+ (g) 1352.871 1350.532 ± 0.041 kJ/mol 47.99765 ± 0.00090 12596-82-6*0 2-Cyclopropyn-1-yl anion [C(CC)]- (g) 664.8 672.1 ± 1.6 kJ/mol 36.0326 ± 0.0024 500574-36-7*0 Ketene cation [CH2CO]+ (g) 882.22 879.05 ± 0.12 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 iso-Proplylide [CH3CHCH3]- (g) 128.6 110.2 ± 1.6 kJ/mol 43.0882 ± 0.0024 25012-80-0*0 Oxoethenylium [HCCO]+ (g) 1139.7 1142.4 ± 2.1 kJ/mol 41.0282 ± 0.0016 92056-63-8*0 Hydrogen fluoride HF (aq, 55 H2O) -321.17 ± 0.16 kJ/mol 20.006343 ± 0.000070 7664-39-3*905 Aminooxy anion [NH2O]- (g) 47.5 40.5 ± 1.7 kJ/mol 32.02257 ± 0.00034 51375-41-8*0 Aminomethyliumylidene [CNH2]+ (g) 1168.3 1165.1 ± 2.2 kJ/mol 28.03277 ± 0.00082 86784-42-1*0 Fluorine atom cation F+ (g) 1758.306 1760.604 ± 0.048 kJ/mol 18.99785462 ± 0.00000050 14701-13-4*0 Bicyclo[1.1.0]buta-1,3-diene-2,4-diyl C(CC)C (g) 1047.47 1055.06 ± 0.73 kJ/mol 48.0428 ± 0.0032 12184-80-4*0 Chlorine difluoride cation [ClFF]+ (g) 1346.3 1344.9 ± 2.1 kJ/mol 73.44896 ± 0.00090 86825-59-4*0 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) 1165.5 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) 833.5 820.3 ± 2.2 kJ/mol 48.0407 ± 0.0010 112465-88-0*0 Methoxyoxoniumylidene [CH3OO]+ (g) 1012.9 1004.6 ± 2.0 kJ/mol 47.0328 ± 0.0010 86475-50-5*0 Hydrogen difluoride cation [FFH]+ (g, singlet) 1174.3 1171.3 ± 1.5 kJ/mol 39.004198 ± 0.000070 *126950-54-7*2 Dioxirane anion [CH2(OO)]- (g) -173.0 -179.8 ± 3.4 kJ/mol 46.0259 ± 0.0010 *157-26-6*0 Dioxymethyl anion [CH2OO]- (g) 54.9 49.8 ± 1.4 kJ/mol 46.0259 ± 0.0010 93207-29-5*0 Triiodine cation [I3]+ (g) 946.1 941.0 ± 4.1 kJ/mol 380.712861 ± 0.000090 12596-32-6*0 Chlorine difluoride anion [ClFF]- (g) -319.0 -319.0 ± 2.2 kJ/mol 73.45005 ± 0.00090 91419-41-9*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 Hydrogen chloride HCl (aq, 2439 H2O) -166.712 ± 0.024 kJ/mol 36.46064 ± 0.00090 7647-01-0*951 Diazenium [NH2NH]+ (g) 968.59 957.33 ± 0.76 kJ/mol 31.03675 ± 0.00025 37369-93-0*0 Nitrate [ON(O)O]- (aq) -206.64 ± 0.18 kJ/mol 62.00549 ± 0.00090 14797-55-8*800 2-Propanol CH3CH(OH)CH3 (cr,l) -306.12 -318.93 ± 0.36 kJ/mol 60.0950 ± 0.0025 67-63-0*500 1-Propanol CH3CH2CH2OH (cr,l) -290.54 -302.72 ± 0.24 kJ/mol 60.0950 ± 0.0025 71-23-8*500 Oxazirinyl cation [C(NO)]+ (g) 1565.4 1566.1 ± 2.3 kJ/mol 42.01629 ± 0.00086 *228850-18-8*0 Oxazirinyl anion [C(NO)]- (g) 448.1 448.8 ± 2.4 kJ/mol 42.01739 ± 0.00086 28269-68-3*0 Cyclopropylide [CH(CH2CH2)]- (g) 264.7 251.9 ± 1.8 kJ/mol 41.0723 ± 0.0024 1724-45-4*0 Peroxychloric acid HOOCl(O)O (g) 77.5 69.3 ± 2.6 kJ/mol 100.4582 ± 0.0015 177778-91-5*0 1-Methoxyethenol CH2C(OH)OCH3 (g, anti-syn) -284.8 -304.1 ± 1.7 kJ/mol 74.0785 ± 0.0025 4453-91-2*1 Deuterium hydride cation [HD]+ (g) 1490.498 1490.587 ± 0.000 kJ/mol 3.021493 ± 0.000070 12181-16-7*0 Oxobromonium [BrO]+ (g) 1139.3 1131.6 ± 1.5 kJ/mol 95.9029 ± 0.0010 142315-39-7*0 Ethyl formate HC(O)OCH2CH3 (cr,l) -426.0 ± 1.2 kJ/mol 74.0785 ± 0.0025 109-94-4*500 Nitrosyl nitrate ONONO2 (g, trans) 48.3 40.3 ± 1.8 kJ/mol 92.0111 ± 0.0012 15969-55-8*1 Hydrooxonitrate [HNO]- (g) 78.59 75.68 ± 0.99 kJ/mol 31.01463 ± 0.00032 66057-02-1*0 Hydrogen chloride HCl (aq, 1500 H2O) -166.636 ± 0.025 kJ/mol 36.46064 ± 0.00090 7647-01-0*840 Hypobromous acid cation [HOBr]+ (g) 974.92 964.30 ± 0.53 kJ/mol 96.9108 ± 0.0010 154804-02-1*0 Propionic acid CH3CH2C(O)OH (g, anti) -415.8 -433.4 ± 1.4 kJ/mol 74.0785 ± 0.0025 79-09-4*2 Aminomethyl anion [CH2NH2]- (g) 209.4 199.1 ± 2.1 kJ/mol 30.04975 ± 0.00085 74215-21-7*0 Hydroxyimidogen anion [NOH]- (g) 229.9 227.4 ± 2.3 kJ/mol 31.01463 ± 0.00032 *35337-59-8*0 Methylammoniumyl [CH3NH2]+ (g) 865.76 851.83 ± 0.30 kJ/mol 31.05659 ± 0.00088 34516-31-9*0 Water H2O (l, eq.press.) -285.832 ± 0.026 kJ/mol 18.01528 ± 0.00033 7732-18-5*589 Cyanogen cation [NCCN]+ (g) 1598.22 1600.44 ± 0.43 kJ/mol 52.0343 ± 0.0016 37354-81-7*0 Isocyanogen CNCN (g) 411.0 413.3 ± 1.6 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 Tetranitrogen cation [NNNN]+ (g) 1392.8 1392.5 ± 1.5 kJ/mol 56.02641 ± 0.00028 12185-04-5*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 Acetylene anion [HCCH]- (g, cis ?) 380.1 380.3 ± 1.9 kJ/mol 26.0378 ± 0.0016 50443-89-5*2 Cyanomethyliumylidene [CCN]+ (g) 1719.8 1725.3 ± 2.1 kJ/mol 38.0276 ± 0.0016 76619-90-4*0 Cyanomethylidyne anion [CCN]- (g) 410.0 413.7 ± 2.2 kJ/mol 38.0287 ± 0.0016 12373-35-2*0 2,3-didehydro-1H-azirin-1-yl N(CC) (g) 720.3 724.4 ± 2.1 kJ/mol 38.0281 ± 0.0016 439586-06-8*0 Isocyanomethylium [CH2NC]+ (g) 1272.7 1270.5 ± 2.2 kJ/mol 40.0435 ± 0.0016 78269-43-9*0 Cyanoaminylium [HNCN]+ (g) 1363.2 1360.1 ± 2.5 kJ/mol 41.03157 ± 0.00082 205443-18-1*0 Cyanoamidogen anion [HNCN]- (g) 70.8 67.8 ± 1.4 kJ/mol 41.03267 ± 0.00082 67131-47-9*0 Dinitrogen pentoxide O2NONO2 (cr,l) -41.04 ± 0.42 kJ/mol 108.0105 ± 0.0015 10102-03-1*500 Cyanamide NH2CN (g) 140.8 134.5 ± 1.5 kJ/mol 42.04006 ± 0.00082 420-04-2*0 Diazomethylene CNN (g) 579.3 580.0 ± 3.8 kJ/mol 40.02418 ± 0.00081 2468-81-7*0 Trichloromethylium [CCl3]+ (g) 854.36 852.84 ± 0.93 kJ/mol 118.3683 ± 0.0028 27130-34-3*0 Dichloromethyliumyl [CCl2]+ (g) 1121.6 1122.6 ± 1.8 kJ/mol 82.9156 ± 0.0020 55945-51-2*0 Bromine atom Br (g, 2P3/2) 117.914 111.851 ± 0.056 kJ/mol 79.90400 ± 0.00100 10097-32-2*1 Fluorosyl fluoride cation [FFO]+ (g, quartet) 1413.0 1413.4 ± 3.5 kJ/mol 53.99566 ± 0.00030 *86825-50-5*1 Methylaminilium [CH3NH]+ (g) 1134.9 1125.1 ± 2.1 kJ/mol 30.04865 ± 0.00085 49784-84-1*0 Hydrogen chloride HCl (aq, 140 H2O) -165.945 ± 0.026 kJ/mol 36.46064 ± 0.00090 7647-01-0*907 2-Propenylidyne anion [CH2CHC]- (g) 464.4 460.7 ± 1.8 kJ/mol 39.0565 ± 0.0024 120126-89-8*0 Hydrogen chloride HCl (aq, 74 H2O) -165.546 ± 0.027 kJ/mol 36.46064 ± 0.00090 7647-01-0*953 Ethanium [C2H7]+ (g, classical Cs I) 888.7 870.3 ± 1.8 kJ/mol 31.0764 ± 0.0017 24669-33-8*2 2-Propen-3-yliumylidene [CHCHCH]+ (g) 1494.7 1491.7 ± 1.7 kJ/mol 39.0554 ± 0.0024 84654-86-4*0 2-Propenylidene anion [CHCHCH]- (g) 535.9 532.6 ± 1.8 kJ/mol 39.0565 ± 0.0024 98705-30-7*0 Ethanium [C2H7]+ (g, classical Cs II) 895.1 877.3 ± 1.9 kJ/mol 31.0764 ± 0.0017 24669-33-8*3 Trioxidanylium [HOOO]+ (g) 1070.4 1064.2 ± 1.4 kJ/mol 49.00559 ± 0.00090 74241-49-9*0 Dibromine Br2 (aq) -2.16 ± 0.20 kJ/mol 159.8080 ± 0.0020 7726-95-6*800 Chloromethane cation [CH3Cl]+ (g) 1014.65 1007.89 ± 0.19 kJ/mol 50.4867 ± 0.0012 12538-71-5*0 Hydroxyoxoammoniumyl [HONO]+ (g) 984.1 977.7 ± 1.8 kJ/mol 47.01293 ± 0.00061 80371-48-8*0 Hydrogen bromide HBr (aq, 2570 H2O) -120.67 ± 0.15 kJ/mol 80.9119 ± 0.0010 10035-10-6*952 Chlorosyl chloride cation [ClClO]+ (g) 1132.6 1130.8 ± 2.0 kJ/mol 86.9043 ± 0.0018 *86825-56-1*0 Hydrogen fluoride HF (aq, 23 H2O) -321.06 ± 0.16 kJ/mol 20.006343 ± 0.000070 7664-39-3*903 Cyanogen bromide anion [BrCN]- (g) 57.8 54.2 ± 3.8 kJ/mol 105.9220 ± 0.0013 54092-05-6*0 Bromofluoromethane CH2FBr (g) -197.4 -211.9 ± 4.9 kJ/mol 112.9290 ± 0.0013 373-52-4*0 Carbon atom C (g, triplet) 711.397 716.882 ± 0.047 kJ/mol 12.01070 ± 0.00080 7440-44-0*1 Chlorosyl chloride anion [ClClO]- (g) -185.4 -184.7 ± 2.3 kJ/mol 86.9053 ± 0.0018 *86825-55-0*0 Fluorodibromomethane CHFBr2 (g) -159.7 -179.3 ± 4.9 kJ/mol 191.8250 ± 0.0022 1868-53-7*0 Difluorochlorobromomethane CF2ClBr (g) -428.9 -439.9 ± 4.9 kJ/mol 165.3642 ± 0.0016 353-59-3*0 Dichlorofluorobromomethane CCl2FBr (g) -228.3 -238.3 ± 4.9 kJ/mol 181.8185 ± 0.0022 353-58-2*0 Dibromofluorochloromethane CBr2FCl (g) -169.9 -186.8 ± 4.9 kJ/mol 226.2698 ± 0.0023 353-55-9*0 Chloroniumyl ion [HCl]+ (g) 1137.797 1137.731 ± 0.0051 kJ/mol 36.46009 ± 0.00090 12258-94-5*0 Krypton cation Kr+ (g) 1350.756 1350.756 ± 0.000 kJ/mol 83.7995 ± 0.1000 16915-28-9*0 Dioxygen O2 (g, triplet) -0.000 -0.000 ± 0.000 kJ/mol 31.99880 ± 0.00060 7782-44-7*1 Chloryl chloride ClCl(O)O (g) 126.1 122.1 ± 1.7 kJ/mol 102.9042 ± 0.0019 117489-73-3*0 Hydrogen bromide HBr (aq, 3000 H2O) -120.69 ± 0.15 kJ/mol 80.9119 ± 0.0010 10035-10-6*842 Methanimine cation [CH2NH]+ (g) 1056.1 1049.3 ± 1.8 kJ/mol 29.04071 ± 0.00083 65130-65-6*0 Hypofluorous acid anion [HOF]- (g, quartet) 155.3 154.7 ± 2.6 kJ/mol 36.00629 ± 0.00031 36505-07-4*2 Trifluorine cation [F3]+ (g) 1529.5 1527.4 ± 2.3 kJ/mol 56.9946610 ± 0.0000015 64710-22-1*0 Ammonium radical NH4 (g) 190.01 179.42 ± 0.43 kJ/mol 18.03850 ± 0.00029 92075-50-8*0 1,2-Difluoroacetylene cation [FCCF]+ (g) 1081.7 1084.5 ± 1.3 kJ/mol 62.0177 ± 0.0016 268566-70-7*0 Methylamine anion [CH3NH2]- (g) 84.1 69.2 ± 2.8 kJ/mol 31.05769 ± 0.00088 81096-79-9*0 Hydroperoxyimidogen HOON (g, trans) 103.3 99.8 ± 2.4 kJ/mol 47.01348 ± 0.00061 877456-58-1*1 Difluorophosgene cation [CF2O]+ (g) 653.44 650.68 ± 0.51 kJ/mol 66.00636 ± 0.00085 73256-56-1*0 Ethylene anion [CH2CH2]- (g, syn ?) 231.5 225.5 ± 2.0 kJ/mol 28.0537 ± 0.0016 34527-91-8*2 Methanimine anion [CH2NH]- (g) 224.4 217.2 ± 2.2 kJ/mol 29.04181 ± 0.00083 127593-73-1*0 Propynylidene HCCCH (g) 543.41 546.40 ± 0.64 kJ/mol 38.0480 ± 0.0024 67152-18-5*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) 13.9 10.9 ± 2.6 kJ/mol 64.4707 ± 0.0012 147723-60-2*1 (Chlorooxy)methylene HCOCl (g, cis) 119.1 117.8 ± 2.7 kJ/mol 64.4707 ± 0.0012 331419-80-8*2 Nirous oxide anion [NNO]- (g) 99.2 96.7 ± 1.9 kJ/mol 44.01343 ± 0.00033 12274-12-3*0 Dibromophosgene CBr2O (l) -144.40 ± 0.95 kJ/mol 187.8181 ± 0.0022 593-95-3*590 Hydrogen bromide HBr (aq, 2000 H2O) -120.64 ± 0.15 kJ/mol 80.9119 ± 0.0010 10035-10-6*841 2-Chloroethanol ClCH2CH2OH (l) -314.95 ± 0.53 kJ/mol 80.5132 ± 0.0019 107-07-3*590 2-Bromoethanol BrCH2CH2OH (l) -274.82 ± 0.47 kJ/mol 124.9645 ± 0.0019 540-51-2*590 Hydrogen fluoride HF (aq, 55.51 H2O) -321.17 ± 0.16 kJ/mol 20.006343 ± 0.000070 7664-39-3*891 Methanol anion [CH3OH]- (g) -89.1 -99.8 ± 2.8 kJ/mol 32.04241 ± 0.00090 68474-04-4*0 Phenylium [C6H5]+ (g, singlet) 1148.39 1135.61 ± 0.85 kJ/mol 77.1034 ± 0.0048 17333-73-2*2 1-Cyclopropene-1,2-diyl CH2(CC) (g) 791.0 790.5 ± 1.5 kJ/mol 38.0480 ± 0.0024 202744-75-0*0 Nitric acid cation [HON(O)O]+ (g) 1029.14 1020.07 ± 0.69 kJ/mol 63.01233 ± 0.00091 272109-63-4*0 m-Benzyne anion [C6H4]- (g) 444.0 435.1 ± 1.3 kJ/mol 76.0965 ± 0.0048 249589-31-9*0 p-Benzyne anion [C6H4]- (g) 464.9 455.3 ± 1.3 kJ/mol 76.0965 ± 0.0048 219298-17-6*0 Aminomethyliumyl [CHNH2]+ (g) 1039.5 1031.9 ± 2.3 kJ/mol 29.04071 ± 0.00083 89302-94-3*0 Cycloheptane CH2(CH2CH2CH2CH2CH2C (cr,l) -126.91 -156.81 ± 0.51 kJ/mol 98.1861 ± 0.0057 291-64-5*500 Imidogen anion [NH]- (g) 322.62 322.67 ± 0.17 kJ/mol 15.015229 ± 0.000099 23841-33-0*0 Ethylbenzene C6H5CH2CH3 (cr,l) -12.55 ± 0.55 kJ/mol 106.1650 ± 0.0064 100-41-4*500 Hydrogen chloride HCl (aq, 150 H2O) -165.979 ± 0.024 kJ/mol 36.46064 ± 0.00090 7647-01-0*829 Phenylacetylene C6H5CCH (cr,l) 273.4 ± 1.1 kJ/mol 102.1332 ± 0.0064 536-74-3*500 Hypofluorous acid cation [HOF]+ (g) 1142.00 1138.99 ± 0.87 kJ/mol 36.00519 ± 0.00031 90243-22-4*0 Phenyloxoniumylidene [C6H5O]+ (g) 901.5 887.2 ± 2.2 kJ/mol 93.1028 ± 0.0048 41071-17-4*0 Anisole C6H5OCH3 (g) -47.79 -72.64 ± 0.80 kJ/mol 108.1378 ± 0.0056 100-66-3*0 Cyclopropenyliumdiyl [CH(CC)]+ (g) 1692.1 1695.0 ± 1.9 kJ/mol 37.0395 ± 0.0024 127476-05-5*0 Hydrogen fluoride HF (aq, 22.2 H2O) -321.06 ± 0.16 kJ/mol 20.006343 ± 0.000070 7664-39-3*888 Fluorobenzene C6H5F (cr,l) -151.81 -149.39 ± 0.89 kJ/mol 96.1023 ± 0.0048 462-06-6*500 1-Ethylium-1-yl [CH3CH]+ (g) 1182.0 1174.7 ± 3.2 kJ/mol 28.0526 ± 0.0016 85944-79-2*0 Ethylidene anion [CH3CH]- (g) 325.7 318.4 ± 1.8 kJ/mol 28.0537 ± 0.0016 35829-99-3*0 Bromobenzene C6H5Br (cr,l) 59.9 ± 1.3 kJ/mol 157.0079 ± 0.0049 108-86-1*500 Cyclopropynyl anion [CH(CC)]- (g) 518.0 521.0 ± 1.1 kJ/mol 37.0406 ± 0.0024 136861-42-2*0 Carbon atom C (g, singlet) 833.328 838.474 ± 0.047 kJ/mol 12.01070 ± 0.00080 7440-44-0*2 Hydrogen fluoride HF (aq, 37 H2O) -321.12 ± 0.16 kJ/mol 20.006343 ± 0.000070 7664-39-3*890 Acetone CH3C(O)CH3 (cr,l) -245.03 -248.15 ± 0.36 kJ/mol 58.0791 ± 0.0025 67-64-1*500 Tribromine Br3 (g) 155.9 134.2 ± 3.2 kJ/mol 239.7120 ± 0.0030 11094-39-6*0 Chloryl ion [OClO]+ (g) 1100.15 1097.49 ± 0.52 kJ/mol 67.4510 ± 0.0011 25052-55-5*0 Propionaldehyde CH3CH2CHO (cr,l) -218.19 -216.73 ± 0.29 kJ/mol 58.0791 ± 0.0025 123-38-6*500 trans-1,2-Dibromoethene CHBrCHBr (g, trans) 121.2 101.4 ± 2.1 kJ/mol 185.8453 ± 0.0026 590-12-5*0 1,1-Dibromoethene CH2CBr2 (g) 125.1 104.8 ± 2.2 kJ/mol 185.8453 ± 0.0026 593-92-0*0 Norbornadiene (CHCH)(CHCH2CH)(CHCH (g) 267.2 241.8 ± 1.1 kJ/mol 92.1384 ± 0.0056 121-46-0*0 Monoammonium succinate (CH2C(O)OH)2(NH3) (cr) -1067.98 ± 0.72 kJ/mol 135.1186 ± 0.0035 38457-08-8*510 Diammonium succinate (CH2COOH)2(NH3)2 (cr) -1182.52 ± 0.48 kJ/mol 152.1492 ± 0.0035 2226-88-2*510 Aminomethylene anion [CHNH2]- (g) 353.0 346.2 ± 2.3 kJ/mol 29.04181 ± 0.00083 207914-86-1*0 Ammonium chloride (NH4)Cl (cr) -311.556 -314.717 ± 0.063 kJ/mol 53.49120 ± 0.00095 12125-02-9*510 Ammonium bromide (NH4)Br (cr) -253.69 -270.26 ± 0.16 kJ/mol 97.9425 ± 0.0010 12124-97-9*510 Acrolein CH2CHCHO (g, cis) -46.6 -56.9 ± 1.4 kJ/mol 56.0633 ± 0.0024 107-02-8*2 Formaldehyde anion [CH2O]- (g) -26.7 -28.3 ± 2.0 kJ/mol 30.02653 ± 0.00087 27837-46-3*0 Ethenedione OCCO (g) 14.0 16.5 ± 2.3 kJ/mol 56.0202 ± 0.0017 4363-38-6*0 Ethenedione cation [OCCO]+ (g) 909.7 912.8 ± 2.3 kJ/mol 56.0197 ± 0.0017 12541-99-0*0 Hypochlorous acid cation [HOCl]+ (g) 998.91 995.87 ± 0.90 kJ/mol 52.45949 ± 0.00095 71606-47-8*0 Hypochlorous acid anion [HOCl]- (g) 198.7 198.4 ± 2.5 kJ/mol 52.46059 ± 0.00095 34524-94-2*0 Formaldehyde CH2O (g, triplet) 196.014 192.683 ± 0.097 kJ/mol 30.02598 ± 0.00087 50-00-0*1 Tribromide [Br3]- (g) -287.4 -308.4 ± 1.9 kJ/mol 239.7125 ± 0.0030 14522-80-6*0 3-Imino-2-propen-1-ylidene CHCHCNH (g, anti-singlet) 532.9 527.9 ± 1.8 kJ/mol 53.0627 ± 0.0024 916765-05-4*12 3-Imino-2-propen-1-ylidene CHCHCNH (g, syn-triplet) 572.5 567.3 ± 2.0 kJ/mol 53.0627 ± 0.0024 916765-05-4*22 2-(Methylidyneamino)ethenyl CHCHNCH (g, syn-singlet) 604.4 599.6 ± 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 Bromine dioxide OBrO (g) 167.2 157.6 ± 3.0 kJ/mol 111.9028 ± 0.0012 21255-83-4*0 1-Cyanovinylium [CH2CCN]+ (g) 1318.7 1317.5 ± 2.2 kJ/mol 52.0542 ± 0.0024 85399-09-3*0 Triazirinylium ion [N(NN)]+ (g) 1608.8 1605.9 ± 1.6 kJ/mol 42.01967 ± 0.00021 92220-05-8*0 Triazirine HN(NN) (g) 464.0 457.6 ± 2.6 kJ/mol 43.02816 ± 0.00022 157-29-9*0 Tetraoxygen O4 (g, C2h singlet) 145.8 142.2 ± 3.8 kJ/mol 63.9976 ± 0.0012 12596-83-7*22 Oxygen difluoride cation [FOF]+ (g) 1292.11 1289.59 ± 0.66 kJ/mol 53.99566 ± 0.00030 39432-25-2*0 Tetraoxodinitrogen cation [O2NNO2]+ (g) 1030.6 1025.1 ± 2.6 kJ/mol 92.0105 ± 0.0012 64476-91-1*0 Iodine monochloride ICl (cr) -36.511 -35.537 ± 0.063 kJ/mol 162.35717 ± 0.00090 7790-99-0*510 Hydrazine NH2NH2 (cr,l) 57.24 50.68 ± 0.18 kJ/mol 32.04524 ± 0.00031 302-01-2*500 Chlorodioxidenium [ClOO]+ (g) 1202.7 1200.4 ± 3.4 kJ/mol 67.4510 ± 0.0011 64710-10-7*0 Peroxynitrous acid HOONO (g) -5.81 -11.64 ± 0.36 kJ/mol 63.01288 ± 0.00091 14691-52-2*0 Cyclopropylium [CH(CH2CH2)]+ (g) 1104.5 1093.0 ± 2.5 kJ/mol 41.0713 ± 0.0024 1724-43-2*0 Acetic acid CH3C(O)OH (aq, 1000 H2O) -484.91 ± 0.23 kJ/mol 60.0520 ± 0.0017 64-19-7*839 Hydrogen difluoride cation [(HF)(F)]+ (g, triplet) 1267.6 1265.4 ± 4.1 kJ/mol 39.004198 ± 0.000070 *126950-54-7*1 Methyl acetate CH3C(O)OCH3 (l) -445.74 ± 0.61 kJ/mol 74.0785 ± 0.0025 79-20-9*500 Acetonitrile CH3CN (cr,l) 40.59 ± 0.23 kJ/mol 41.0520 ± 0.0016 75-05-8*500 Dioxymethylidyne cation [COO]+ (g, doublet) 1436.6 1439.0 ± 2.7 kJ/mol 44.00895 ± 0.00100 *791121-04-5*2 Trioxirane O(OO) (g) 272.7 270.1 ± 1.3 kJ/mol 47.99820 ± 0.00090 153851-84-4*0 Dihydrogen fluoride (HF)(H) (g) -56.5 -54.1 ± 1.7 kJ/mol 21.01428 ± 0.00014 12592-22-2*2 Azide [NNN]- (aq) 272.56 ± 0.48 kJ/mol 42.02077 ± 0.00021 14343-69-2*800 Propionic acid CH3CH2C(O)OH (cr,l) -505.47 -509.61 ± 0.18 kJ/mol 74.0785 ± 0.0025 79-09-4*500 Ethylene glycol (CH2OH)2 (cr,l) -448.73 -455.24 ± 0.37 kJ/mol 62.0678 ± 0.0018 107-21-1*500 Dioxymethylidyne cation [(C)(OO)]+ (g, vdW quartet) 1388.2 1391.7 ± 3.2 kJ/mol 44.00895 ± 0.00100 *791121-04-5*101 Dioxiranylidene cation [C(OO)]+ (g) 1409.1 1410.3 ± 2.6 kJ/mol 44.00895 ± 0.00100 *138832-57-2*0 Oxalic acid (C(O)OH)2 (cr) -819.57 -829.66 ± 0.42 kJ/mol 90.0349 ± 0.0020 144-62-7*500 Dimethylamine (CH3)2NH (l) -43.60 ± 0.39 kJ/mol 45.0837 ± 0.0017 124-40-3*500 Hydroxylamine NH2OH (aq, undissoc) -97.1 ± 2.2 kJ/mol 33.02996 ± 0.00037 7803-49-8*1000 Propane cation [CH3CH2CH3]+ (g) 974.6 954.7 ± 1.7 kJ/mol 44.0951 ± 0.0025 34479-70-4*0 Tetraoxidanyl HOOOO (g, cis) 53.0 46.0 ± 5.1 kJ/mol 65.0055 ± 0.0012 69696-93-1*2 Trimethylamine (CH3)3N (l) -49.37 ± 0.99 kJ/mol 59.1103 ± 0.0025 75-50-3*500 1-Propynylium [CH3CC]+ (g) 1546.9 1544.9 ± 3.1 kJ/mol 39.0554 ± 0.0024 24858-94-4*0 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) 1824.8 1827.5 ± 3.3 kJ/mol 52.0343 ± 0.0016 *78800-21-2*1 Hydronium radical (H2O)(H) (g, vdW) -18.5 -21.6 ± 2.1 kJ/mol 19.02322 ± 0.00037 12168-76-2*100 Hydroxyoxoammoniumyl [HONO]+ (g, trans) 984.1 977.7 ± 1.8 kJ/mol 47.01293 ± 0.00061 80371-48-8*1 Cyanoaminyliumyl [NCN]+ (g) 1671.6 1672.9 ± 2.6 kJ/mol 40.02363 ± 0.00081 316122-03-9*0 Cyanoamidogen anion [NCN]- (g) 210.92 210.85 ± 0.77 kJ/mol 40.02473 ± 0.00081 189879-95-6*0 Cyanamide NH2CN (cr) 58.89 ± 0.54 kJ/mol 42.04006 ± 0.00082 420-04-2*500 Peroxychlorous acid HOOClO (g, anti) 103.5 97.6 ± 2.5 kJ/mol 84.4588 ± 0.0013 177778-92-6*2 Diazomethyliumyl [CNN]+ (g) 1641.2 1642.4 ± 4.1 kJ/mol 40.02363 ± 0.00081 307495-90-5*0 Diazomethylene anion [CNN]- (g) 408.3 408.5 ± 3.8 kJ/mol 40.02473 ± 0.00081 205498-92-6*0 3H-Diazirin-3-ylidene C(NN) (g) 578.8 579.2 ± 2.7 kJ/mol 40.02418 ± 0.00081 253308-70-2*0 Trioxidanyl HOOO (g) 25.32 23.23 ± 0.13 kJ/mol 49.00614 ± 0.00090 12500-78-6*0 Dioxygen difluoride OOF2 (g) 75.1 71.6 ± 3.6 kJ/mol 69.99561 ± 0.00060 183051-89-0*0 Isoprene CH2C(CH3)CHCH2 (cr,l) 48.79 ± 0.70 kJ/mol 68.1170 ± 0.0040 78-79-5*500 Chloromethyliumylidene [CCl]+ (g) 1282.6 1285.7 ± 2.4 kJ/mol 47.4629 ± 0.0012 69773-94-0*0 Chloromethylidyne anion [CCl]- (g) 319.7 323.4 ± 2.5 kJ/mol 47.4639 ± 0.0012 117129-77-8*0 Dioxohydrazine ONNO (g, cis) 172.89 171.12 ± 0.14 kJ/mol 60.01228 ± 0.00062 16824-89-8*2 Isocyanic fluoride FNC (g) 301.3 303.1 ± 1.8 kJ/mol 45.01584 ± 0.00080 16992-26-0*0 Cycloprop-1-enylium [CH2(CHC)]+ (g) 1502.3 1498.0 ± 2.2 kJ/mol 39.0554 ± 0.0024 117067-78-4*0 Cycloprop-1-enylide [CH2(CHC)]- (g) 373.5 369.0 ± 2.2 kJ/mol 39.0565 ± 0.0024 80251-77-0*0 Deuterium hydride HD (g) 0.328 0.319 ± 0.000 kJ/mol 3.022042 ± 0.000070 13983-20-5*0 Peroxyhypochlorous acid anion [HOOCl]- (g, cis quartet) -32.2 -34.0 ± 2.6 kJ/mol 68.4600 ± 0.0011 *67952-08-3*2 Cycloprop-2-enylide [CH(CHCH)]- (g) 514.8 511.8 ± 2.2 kJ/mol 39.0565 ± 0.0024 20829-57-6*0 1,1,1-Trichloroethane CH3CCl3 (l) -177.54 ± 0.49 kJ/mol 133.4033 ± 0.0031 71-55-6*500 Bromoniumyl [HBr]+ (g) 1097.73 1089.89 ± 0.14 kJ/mol 80.9114 ± 0.0010 12258-64-9*0 Nitrous acid anion [HONO]- (g, cis) -105.85 -110.48 ± 0.78 kJ/mol 47.01403 ± 0.00061 256393-36-9*2 Vinyl chloride CH2CHCl (cr,l) -2.7 1.9 ± 1.9 kJ/mol 62.4979 ± 0.0018 75-01-4*500 Poly(vinylchloride) CH2CHCl (s, poly) -84.6 -94.0 ± 1.3 kJ/mol 62.4979 ± 0.0018 9002-86-2*500 Hydrogen chloride HCl (aq, 3000 H2O) -166.741 ± 0.024 kJ/mol 36.46064 ± 0.00090 7647-01-0*842 Isocyanogen chloride ClNC (g) 314.5 316.2 ± 2.4 kJ/mol 61.4701 ± 0.0012 75754-69-7*0 1,1-Dichloroethene CH2CCl2 (l) -23.80 ± 0.50 kJ/mol 96.9427 ± 0.0024 75-35-4*500 Dihydrogen H2 (g, ortho) 1.417 0.019 ± 0.000 kJ/mol 2.01588 ± 0.00014 1333-74-0*1 Trifluorine F3 (g) 80.6 81.9 ± 2.6 kJ/mol 56.9952096 ± 0.0000015 73455-86-4*0 Difluorodioxidanium [FOOF]+ (g, trans) 1283.6 1279.1 ± 2.3 kJ/mol 69.99506 ± 0.00060 *7783-44-0*1 1-Ethenylium-1-yl [CCH2]+ (g) 1507.1 1507.1 ± 2.1 kJ/mol 26.0367 ± 0.0016 80541-07-7*0 Dichloromethane CH2Cl2 (l) -122.57 ± 0.53 kJ/mol 84.9320 ± 0.0020 75-09-2*590 Dihydrogen cation [H2]+ (g, ortho) 1489.060 1488.480 ± 0.000 kJ/mol 2.01533 ± 0.00014 12184-90-6*1 1-Methyl-1-ethylium-1-yl [CH3CCH3]+ (g) 1058.4 1045.9 ± 2.5 kJ/mol 42.0792 ± 0.0024 121408-19-3*0 Trihydrogen H(HH) (g, 2p 2A2" Ry) 756.931 754.146 ± 0.015 kJ/mol 3.02382 ± 0.00021 12184-91-7*2 Cyclohexane CH2(CH2CH2CH2CH2CH2) (l) -156.27 ± 0.36 kJ/mol 84.1595 ± 0.0049 110-82-7*500 Isopropylidene anion [CH3CCH3]- (g) 282.6 268.5 ± 2.6 kJ/mol 42.0803 ± 0.0024 *121408-19-3*0 Ammonia anion [NH3]- (g) 94.3 87.3 ± 2.4 kJ/mol 17.03111 ± 0.00022 37353-00-7*0 Difluoromethylene anion [CF2]- (g) -211.18 -210.00 ± 0.60 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 Carbon dioxide cation [CO2]+ (g, quartet) 1335.0 1335.5 ± 2.4 kJ/mol 44.00895 ± 0.00100 12181-61-2*1 Isocyanogen bromide BrNC (g) 341.1 335.4 ± 3.4 kJ/mol 105.9214 ± 0.0013 65997-98-0*0 Tetraazatetrahedrane N(N(N)N) (g, Td) 763.7 757.2 ± 1.7 kJ/mol 56.02696 ± 0.00028 12596-63-3*0 Cyclopropenylidene anion [C(CHCH)]- (g) 544.2 543.8 ± 2.2 kJ/mol 38.0485 ± 0.0024 *16165-40-5*0 Hydrochlorate ion [HCl]- (g) -25.2 -24.2 ± 2.5 kJ/mol 36.46119 ± 0.00090 63099-75-2*0 Trioxidane HOOOH (g) -82.04 -90.64 ± 0.70 kJ/mol 50.01408 ± 0.00091 14699-99-1*0 Difluorovinylidene CCF2 (g) 129.4 130.6 ± 2.2 kJ/mol 62.0182 ± 0.0016 41895-33-4*0 Fluoroethynylium [CCF]+ (g) 1536.2 1540.9 ± 2.3 kJ/mol 43.0193 ± 0.0016 268566-69-4*0 Bromoacetylene HCCBr (g) 281.7 275.2 ± 1.6 kJ/mol 104.9333 ± 0.0019 593-61-3*0 n-Heptane CH3(CH2)5CH3 (cr,l) -201.72 -224.18 ± 0.48 kJ/mol 100.2019 ± 0.0057 142-82-5*500 1,2-Propadien-1-ylium-1-yl-3-ylidene [CCC]+ (g, lin) 1981.5 1989.3 ± 2.2 kJ/mol 36.0316 ± 0.0024 118090-85-0*1 Methylamine CH3NH2 (l) -45.41 ± 0.47 kJ/mol 31.05714 ± 0.00088 74-89-5*500 n-Octane CH3(CH2)6CH3 (cr,l) -226.65 -249.78 ± 0.67 kJ/mol 114.2285 ± 0.0065 111-65-9*500 Isocyanogen iodide INC (g) 341.8 342.1 ± 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 Chloro(chlorooxy)methylene ClCOCl (g, trans singlet) 98. 101. ± 15. kJ/mol 98.9155 ± 0.0020 479587-31-0*11 2-Oxo-1-ethylium-1-yl [HCC(O)H]+ (g, anti-quartet) 1289.5 1286.1 ± 2.7 kJ/mol 42.0361 ± 0.0016 214464-96-7*11 Chlorooxomethylium [ClCO]+ (g) 783.7 783.9 ± 2.2 kJ/mol 63.4623 ± 0.0012 38264-03-8*0 Oxoethylidene anion [HCC(O)H]- (g, anti-gauche) 87.0 83.6 ± 2.3 kJ/mol 42.0372 ± 0.0016 106543-38-8*1 1,3-Propanediyl CH2CH2CH2 (g, triplet) 320.0 308.2 ± 1.7 kJ/mol 42.0797 ± 0.0024 32458-33-6*1 2-Iodoethanol ICH2CH2OH (l) -207.2 ± 2.4 kJ/mol 171.9650 ± 0.0017 624-76-0*590 1,3-Butadiyne cation [HCCCCH]+ (g) 1439.69 1441.55 ± 0.81 kJ/mol 50.0581 ± 0.0032 55468-55-8*0 Carbon suboxide cation [OCCCO]+ (g) 928.3 931.8 ± 1.3 kJ/mol 68.0304 ± 0.0025 151528-67-5*0 Carbon suboxide anion [OCCCO]- (g) -131.5 -128.0 ± 2.5 kJ/mol 68.0314 ± 0.0025 109362-94-9*0 Benzene anion [C6H6]- (g) 209.1 197.2 ± 1.2 kJ/mol 78.1124 ± 0.0048 34562-85-1*0 NON cation [NON]+ (g) 1443.9 1444.1 ± 2.8 kJ/mol 44.01233 ± 0.00033 *227934-46-5*0 Hydrogen fluoride HF (aq, 18.5 H2O) -321.03 ± 0.16 kJ/mol 20.006343 ± 0.000070 7664-39-3*887 Hydrazoic acid cation [HNNN]+ (g) 1333.62 1327.94 ± 0.83 kJ/mol 43.02761 ± 0.00022 58852-14-5*0 o-Benzyne C6H4 (g, triplet) 625.4 616.1 ± 1.1 kJ/mol 76.0960 ± 0.0048 462-80-6*1 2-Propen-3-ylium-1-ylidyne [CHCHC]+ (g) 1791.1 1792.7 ± 2.6 kJ/mol 38.0474 ± 0.0024 161054-36-0*0 m-Benzyne C6H4 (g) 526.8 518.4 ± 1.2 kJ/mol 76.0960 ± 0.0048 1828-89-3*0 Vinylidene CCH2 (g, triplet) 610.45 610.15 ± 0.51 kJ/mol 26.0373 ± 0.0016 2143-69-3*1 Propenediylidene anion [CHCHC]- (g) 588.8 590.0 ± 2.3 kJ/mol 38.0485 ± 0.0024 *161054-36-0*0 p-Benzyne cation [C6H4]+ (g) 1425.7 1418.4 ± 2.1 kJ/mol 76.0954 ± 0.0048 121058-09-1*0 p-Benzyne C6H4 (g) 586.9 577.5 ± 1.2 kJ/mol 76.0960 ± 0.0048 3355-34-8*0 Toluene C6H5CH3 (l) 19.72 11.97 ± 0.34 kJ/mol 92.1384 ± 0.0056 108-88-3*500 Chlorine chlorite ClOClO (g, cis) 177.4 175.0 ± 2.2 kJ/mol 102.9042 ± 0.0019 105206-44-8*2 1,5-Hexadiene CH2CHCH2CH2CHCH2 (cr,l) 54.42 ± 0.32 kJ/mol 82.1436 ± 0.0049 592-42-7*500 Hydrogen fluoride HF (aq, 400 H2O) -321.47 ± 0.16 kJ/mol 20.006343 ± 0.000070 7664-39-3*832 Cyclopentadienylium [CH(CHCHCHCH)]+ (g) 1087.60 1074.73 ± 0.93 kJ/mol 65.0927 ± 0.0040 29661-18-5*0 Triiodine I3 (g) 153.4 149.4 ± 3.6 kJ/mol 380.713410 ± 0.000090 12596-31-5*0 Cycloheptene CH2(CHCHCH2CH2CH2CH2 (cr,l) -25.5 -46.6 ± 1.7 kJ/mol 96.1702 ± 0.0057 628-92-2*500 Carbon monoxide anion [CO]- (g) 30.0 33.7 ± 2.3 kJ/mol 28.01065 ± 0.00085 12539-63-8*0 Cycloheptatriene CH2(CHCHCHCHCHCH) (cr,l) 153.67 144.89 ± 0.97 kJ/mol 92.1384 ± 0.0056 544-25-2*500 Hydrogen bromide HBr (aq, 1000 H2O) -120.54 ± 0.15 kJ/mol 80.9119 ± 0.0010 10035-10-6*839 Bromosyl bromide BrBrO (g) 178.8 163.0 ± 2.1 kJ/mol 175.8074 ± 0.0020 68322-97-4*0 Phenylethene C6H5CHCH2 (cr,l) 104.30 ± 0.48 kJ/mol 104.1491 ± 0.0064 100-42-5*500 Hydrogen chloride HCl (aq, 200 H2O) -166.104 ± 0.024 kJ/mol 36.46064 ± 0.00090 7647-01-0*830 Phenol C6H5OH (cr,l) -146.43 -162.28 ± 0.66 kJ/mol 94.1112 ± 0.0048 108-95-2*500 Anisole C6H5OCH3 (l) -119.56 ± 0.77 kJ/mol 108.1378 ± 0.0056 100-66-3*500 Benzaldehyde C6H5C(O)H (cr,l) -85.8 -86.9 ± 1.1 kJ/mol 106.1219 ± 0.0056 100-52-7*500 Formic acid HC(O)OH (cr,l) -431.55 -424.72 ± 0.20 kJ/mol 46.0254 ± 0.0010 64-18-6*500 Fluorobenzene anion [C6H5F]- (g) -18.3 -30.2 ± 1.8 kJ/mol 96.1029 ± 0.0048 34561-55-2*0 Hydrazoic acid anion [HNNN]- (g, trans) 309.0 302.7 ± 2.3 kJ/mol 43.02871 ± 0.00022 203264-98-6*1 Isodiazene anion [NNH2]- (g) 380.9 374.0 ± 2.1 kJ/mol 30.02991 ± 0.00020 *63986-30-1*0 m-Chlorophenylium [C6H4Cl]+ (g) 1159.8 1149.7 ± 2.6 kJ/mol 111.5481 ± 0.0049 127983-85-1*0 p-Chlorophenylium [C6H4Cl]+ (g) 1147.1 1137.6 ± 2.5 kJ/mol 111.5481 ± 0.0049 42766-43-8*0 o-Chlorophenylium [C6H4Cl]+ (g) 1166.4 1157.2 ± 2.5 kJ/mol 111.5481 ± 0.0049 137963-70-3*0 Methanol dimer (CH3OH)2 (g) -398.5 -419.2 ± 1.4 kJ/mol 64.0837 ± 0.0018 42845-44-3*0 Perchloryl cation [OCl(O)O]+ (g) 1252.1 1246.3 ± 2.5 kJ/mol 83.4504 ± 0.0013 23594-88-9*0 Iodobenzene cation [C6H5I]+ (g) 1022.66 1007.22 ± 0.99 kJ/mol 204.0078 ± 0.0048 38406-85-8*0 Tetrazete N(NNN) (g, D2h) 764.9 759.0 ± 1.8 kJ/mol 56.02696 ± 0.00028 42851-09-2*0 Oxygen difluoride anion [FOF]- (g) -202.0 -201.9 ± 2.7 kJ/mol 53.99675 ± 0.00030 *7783-41-7*0 Nitrobenzene C6H5N(O)O (cr,l) 6.3 ± 1.4 kJ/mol 123.1094 ± 0.0049 98-95-3*500 Dioxodiazoxane ONONO (g, c, p) 125.7 120.4 ± 2.1 kJ/mol 76.01168 ± 0.00091 122413-35-8*3 Hydrogen peroxide H2O2 (cr,l) -193.172 -187.354 ± 0.080 kJ/mol 34.01468 ± 0.00062 7722-84-1*500 Nitric acid HON(O)O (aq, 1 H2O) -186.85 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*801 Nitromethane CH3N(O)O (cr,l) -114.18 -113.00 ± 0.43 kJ/mol 61.0401 ± 0.0010 75-52-5*500 2,2,4-Trimethylpentane (CH3)2CHCH2C(CH3)3 (cr,l) -224.5 -258.9 ± 1.5 kJ/mol 114.2285 ± 0.0065 540-84-1*500 Norbornadiene (CHCH)(CHCH2CH)(CHCH (l) 208.5 ± 1.2 kJ/mol 92.1384 ± 0.0056 121-46-0*500 2,3-Butanedione CH3C(O)C(O)CH3 (cr,l) -365.62 ± 0.53 kJ/mol 86.0892 ± 0.0033 431-03-8*500 Succinic acid (CH2C(O)OH)2 (g) -802.9 -825.1 ± 3.0 kJ/mol 118.0880 ± 0.0034 110-15-6*0 (Z)-Diazene anion [HNNH]- (g, cis) 280.0 273.3 ± 2.0 kJ/mol 30.02991 ± 0.00020 *86631-37-0*0 Formyloxidanyl HC(O)O (g) -125.86 -127.23 ± 0.56 kJ/mol 45.0174 ± 0.0010 16499-21-1*0 1,2-Diiodoethane CH2ICH2I (g) 87.79 73.13 ± 0.90 kJ/mol 281.8621 ± 0.0016 624-73-7*0 1,2-Diiodoethane CH2ICH2I (cr,l) 9.26 ± 0.60 kJ/mol 281.8621 ± 0.0016 624-73-7*500 Helium hydride cation [HeH]+ (g) 1350.148 1348.258 ± 0.000 kJ/mol 5.009993 ± 0.000070 17009-49-3*0 Carbon monoxide CO (g, triplet) 465.579 469.286 ± 0.026 kJ/mol 28.01010 ± 0.00085 630-08-0*1 Xenon hydride cation [XeH]+ (g) 1038.04 1036.26 ± 0.89 kJ/mol 132.2974 ± 0.0200 37276-91-8*0 2-Butanone CH3CH2C(O)CH3 (cr,l) -267.84 -273.33 ± 0.91 kJ/mol 72.1057 ± 0.0033 78-93-3*500 Dioxiranyl HC(OO) (g) 217.4 213.9 ± 2.0 kJ/mol 45.0174 ± 0.0010 120595-16-6*0 Acrolein CH2CHCHO (cr,l) -95.8 ± 1.4 kJ/mol 56.0633 ± 0.0024 107-02-8*500 Peroxyhypochlorous acid cation [HOOCl]+ (g, trans) 1030.3 1024.5 ± 2.5 kJ/mol 68.4589 ± 0.0011 *67952-07-2*1 Nitric acid HON(O)O (aq, 3 H2O) -197.77 ± 0.18 kJ/mol 63.01288 ± 0.00091 7697-37-2*805 Ethenedione anion [OCCO]- (g) -148.4 -145.8 ± 2.4 kJ/mol 56.0207 ± 0.0017 77783-15-4*0 1-Propenylium [CH3CHCH]+ (g, cis) 1231.9 1221.6 ± 1.7 kJ/mol 41.0713 ± 0.0024 50457-58-4*2 1-Propenylide [CH3CHCH]- (g, cis) 204.1 192.8 ± 1.8 kJ/mol 41.0723 ± 0.0024 65887-20-9*2 Urea NH2C(O)NH2 (cr,l) -317.79 -333.39 ± 0.12 kJ/mol 60.05534 ± 0.00091 57-13-6*500 Chlorine hydride oxide HCl(O)(O)O (g) 165.1 155.3 ± 2.5 kJ/mol 84.4588 ± 0.0013 1027055-52-2*0 Hydraziniumyl [NH2NH2]+ (g) 886.6 873.2 ± 2.0 kJ/mol 32.04469 ± 0.00031 20771-51-1*0 Formamide CH(O)NH2 (cr,l) -250.95 ± 0.29 kJ/mol 45.04066 ± 0.00088 75-12-7*500 Nitrosyl nitrite anion [ONONO]- (g, t, t) -103.1 -106.2 ± 2.8 kJ/mol 76.01223 ± 0.00091 *122413-35-8*1 Paraformaldehyde CH2O (cr, paraformaldehyde) -179.2 ± 1.6 kJ/mol 30.02598 ± 0.00087 30525-89-4*500 Nitric acid trihydrate (HON(O)O)(H2O)3 (cr,l) -1062.11 -1055.26 ± 0.21 kJ/mol 117.0587 ± 0.0019 13444-83-2*500 Acrylonitrile CH2CHCN (g, triplet) 446.4 441.0 ± 1.8 kJ/mol 53.0627 ± 0.0024 107-13-1*2 Acrylonitrile CH2CHCN (cr,l) 146.35 154.01 ± 0.81 kJ/mol 53.0627 ± 0.0024 107-13-1*500 Ethoxyethane CH3CH2OCH2CH3 (cr,l) -265.35 -277.67 ± 0.82 kJ/mol 74.1216 ± 0.0033 60-29-7*500 Nitric acid monohydrate (HON(O)O)(H2O) (cr,l) -479.18 -472.68 ± 0.19 kJ/mol 81.0282 ± 0.0012 13444-82-1*500 Isocyanoethene CH2CHNC (g, triplet) 544.1 539.1 ± 1.8 kJ/mol 53.0627 ± 0.0024 14668-82-7*2 Hydrogen difluoride cation [FHF]+ (g, triplet ?) 1241. 1238. ± 17. kJ/mol 39.004198 ± 0.000070 126950-54-7*1 1-Isocyanoethylidene CH3CNC (g) 527.7 523.0 ± 1.1 kJ/mol 53.0627 ± 0.0024 *498544-34-6*0 Hydrogen chloride HCl (aq, 1000 H2O) -166.565 ± 0.024 kJ/mol 36.46064 ± 0.00090 7647-01-0*839 Dioxiranylidene anion [C(OO)]- (g, ?) -110.2 -109.7 ± 3.0 kJ/mol 44.01005 ± 0.00100 *138832-58-3*0 Oxadiazirine cation [O(NN)]+ (g) 1509.9 1507.2 ± 2.4 kJ/mol 44.01233 ± 0.00033 *227934-45-4*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 Cyclobutane CH2(CH2CH2CH2) (l) 3.92 ± 0.41 kJ/mol 56.1063 ± 0.0032 287-23-0*590 Methylcyclopropane CH3CH(CH2CH2) (l) 1.83 ± 0.59 kJ/mol 56.1063 ± 0.0032 594-11-6*590 Oxygen atom hexacation [O]+6 (g) 42035.28 42037.14 ± 0.12 kJ/mol 15.99611 ± 0.00030 14158-22-6*0 NON anion [NON]- (g) 495.3 492.8 ± 2.5 kJ/mol 44.01343 ± 0.00033 *227934-47-6*0 Carbon dioxide anion [CO2]- (g) -340.6 -340.1 ± 2.2 kJ/mol 44.01005 ± 0.00100 14485-07-5*0 Tetraoxygen O4 (g, C2h triplet) 104.4 102.4 ± 3.5 kJ/mol 63.9976 ± 0.0012 12596-83-7*11 Ethyl formate HC(O)OCH2CH3 (g) -375.2 -393.9 ± 1.2 kJ/mol 74.0785 ± 0.0025 109-94-4*0 Hydroxyoxoammoniumyl [HONO]+ (g, cis) 1014.8 1008.4 ± 2.0 kJ/mol 47.01293 ± 0.00061 80371-48-8*2 Acetylene anion [HCCH]- (g) 356.8 356.7 ± 1.9 kJ/mol 26.0378 ± 0.0016 50443-89-5*0 2-Propen-1-ylium-1-ylidene [CH2CHC]+ (g) 1373.1 1369.6 ± 2.0 kJ/mol 39.0554 ± 0.0024 88000-25-3*0 Nitrous acid anion [HONO]- (g, trans) -105.5 -109.4 ± 1.8 kJ/mol 47.01403 ± 0.00061 256393-36-9*1 Cyclopropane cation [CH2(CH2CH2)]+ (g) 1022.3 1006.8 ± 1.6 kJ/mol 42.0792 ± 0.0024 34496-93-0*0 Formylimidogen HC(O)N (g, singlet) 245.3 242.1 ± 3.3 kJ/mol 43.02478 ± 0.00086 42288-92-6*2 Oxonium [H3O]+ (g, para) 605.84 599.09 ± 0.17 kJ/mol 19.02267 ± 0.00037 13968-08-6*2 Tetrabromomethane CBr4 (cr, monoclinic) 48.8 ± 1.4 kJ/mol 331.6267 ± 0.0041 558-13-4*500 Hydrazine monohydrate (NH2NH2)(H2O) (l) -242.67 ± 0.19 kJ/mol 50.06052 ± 0.00053 7803-57-8*500 Tetraiodomethane CI4 (cr, monoclinic) 392.5 ± 8.0 kJ/mol 519.62858 ± 0.00081 507-25-5*500 Bromomethane CH3Br (l) -56.58 -59.60 ± 0.19 kJ/mol 94.9385 ± 0.0013 74-83-9*590 iso-Hexane CH3CH2CH2CH(CH3)2 (cr,l) -180.37 -204.02 ± 0.83 kJ/mol 86.1754 ± 0.0049 107-83-5*500 1-Propen-1-yl-3-ylidene CHCHCH (g, quartet) 657.4 654.0 ± 1.5 kJ/mol 39.0559 ± 0.0024 84654-90-0*1 Acetoxy CH3C(O)O (g, 2A") -182.7 -191.5 ± 1.2 kJ/mol 59.0440 ± 0.0017 13799-69-4*1 Dihydrogen anion [H2]- (g) 253.8 254.7 ± 1.2 kJ/mol 2.01643 ± 0.00014 12184-89-3*0 Iodine monochloride ICl (l) -24.048 ± 0.063 kJ/mol 162.35717 ± 0.00090 7790-99-0*590 Acetoxy CH3C(O)O (g) -182.7 -191.4 ± 1.2 kJ/mol 59.0440 ± 0.0017 13799-69-4*0 Trihydrogen H(HH) (g, 2s 2A1' Ry) 745.878 743.094 ± 0.062 kJ/mol 3.02382 ± 0.00021 12184-91-7*1 Hydrogen iodide HI (aq) -56.826 ± 0.090 kJ/mol 127.912410 ± 0.000076 10034-85-2*800 Nitrosyl nitrate ONONO2 (g, cis-perp) 60.4 52.4 ± 1.9 kJ/mol 92.0111 ± 0.0012 15969-55-8*2 Oxygen atom trication [O]+3 (g) 10249.929 10252.880 ± 0.018 kJ/mol 15.99775 ± 0.00030 14127-64-1*0 Methylaminyliumyl [CH3N]+ (g, doublet ?) 1388.4 1382.1 ± 2.6 kJ/mol 29.04071 ± 0.00083 56924-51-7*1 Isocyanogen bromide anion [BrNC]- (g) 105.0 101.8 ± 4.6 kJ/mol 105.9220 ± 0.0013 *238754-53-5*0 Ethyl bromide CH3CH2Br (l) -55.78 -91.31 ± 0.26 kJ/mol 108.9651 ± 0.0019 74-96-4*500 Peroxyformyl HC(O)OO (g, anti) -90.4 -95.9 ± 1.8 kJ/mol 61.0168 ± 0.0012 56240-83-6*2 Vinyl iodide CH2CHI (g) 139.5 130.6 ± 1.2 kJ/mol 153.9497 ± 0.0016 593-66-8*0 Methylene CH2 (g) 391.061 391.618 ± 0.097 kJ/mol 14.02658 ± 0.00081 2465-56-7*0 Difluorovinylidene cation [CCF2]+ (g) 1181.6 1183.0 ± 2.3 kJ/mol 62.0177 ± 0.0016 268566-71-8*0 Bicyclo[1.1.0]buta-1,3-dien-4-ylium-2-yl [C(CC)C]+ (g) 2087.4 2097.2 ± 2.7 kJ/mol 48.0423 ± 0.0032 289679-91-0*0 Propionic acid CH3CH2C(O)OH (g) -436.41 -454.30 ± 0.60 kJ/mol 74.0785 ± 0.0025 79-09-4*0 Acetaldehyde CH3CHO (cr,l) -187.10 -191.82 ± 0.31 kJ/mol 44.0526 ± 0.0017 75-07-0*500 Hydrogen peroxide cation [H2O2]+ (g, cis, para) 930.98 924.12 ± 0.98 kJ/mol 34.01413 ± 0.00062 12325-10-9*22 1-Propenylium [CH3CHCH]+ (g, trans) 1233.8 1223.4 ± 2.0 kJ/mol 41.0713 ± 0.0024 50457-58-4*1 Chloro(chlorooxy)methylene ClCOCl (g, trans triplet) 101.1 104.7 ± 4.8 kJ/mol 98.9155 ± 0.0020 479587-31-0*12 Hydrogen peroxide cation [H2O2]+ (g, trans, ortho) 897.23 890.25 ± 0.51 kJ/mol 34.01413 ± 0.00062 12325-10-9*11 Fluorosyl fluoride FFO (g, singlet) 227. 225. ± 21. kJ/mol 53.99621 ± 0.00030 86825-57-2*2 2-Oxo-1-ethylium-1-yl [HCC(O)H]+ (g, syn-quartet) 1292.1 1288.7 ± 2.6 kJ/mol 42.0361 ± 0.0016 214464-96-7*12 Oxoethylidene anion [HCC(O)H]- (g, syn-gauche) 92.3 89.1 ± 2.5 kJ/mol 42.0372 ± 0.0016 106543-38-8*2 1-Propenylide [CH3CHCH]- (g, trans) 210.5 199.4 ± 2.1 kJ/mol 41.0723 ± 0.0024 65887-20-9*1 Carbon suboxide OCCCO (cr,l) -131.7 -116.6 ± 1.3 kJ/mol 68.0309 ± 0.0025 504-64-3*500 Hydrazoic acid HNNN (aq) 272.56 ± 0.48 kJ/mol 43.02816 ± 0.00022 7782-79-8*800 Dioxaziridine HN(OO) (g) 277.3 270.6 ± 2.0 kJ/mol 47.01348 ± 0.00061 67394-35-8*0 Difluorodioxidanium [FOOF]+ (g, cis) 1287.1 1283.0 ± 2.3 kJ/mol 69.99506 ± 0.00060 *7783-44-0*2 Diatomic bromine cation [Br2]+ (g) 1060.32 1045.37 ± 0.23 kJ/mol 159.8075 ± 0.0020 12595-71-0*0 m-Benzyne C6H4 (g, triplet) 614.5 605.1 ± 1.4 kJ/mol 76.0960 ± 0.0048 1828-89-3*1 Oxygen atom pentacation [O]+5 (g) 28708.788 28710.646 ± 0.053 kJ/mol 15.99666 ± 0.00030 14127-66-3*0 Chlorine trifluoride cation [FCl(F)F]+ (g) 1053.4 1049.1 ± 2.5 kJ/mol 92.44736 ± 0.00090 478167-77-0*0 Water trimer (H2O)3 (g) -762.73 -776.84 ± 0.21 kJ/mol 54.04584 ± 0.00099 31014-12-7*0 Tetraoxodinitrate anion [O2NNO2]- (g) -184.6 -187.8 ± 2.4 kJ/mol 92.0116 ± 0.0012 63552-02-3*0 Hydroxylamine NH2OH (g) -33.23 -43.60 ± 0.46 kJ/mol 33.02996 ± 0.00037 7803-49-8*0 Nitrogen atom N (g, quartet) 470.579 472.441 ± 0.024 kJ/mol 14.006740 ± 0.000070 17778-88-0*1 mu-Oxodichlorine cation [ClOCl]+ (g) 1130.44 1126.83 ± 0.63 kJ/mol 86.9043 ± 0.0018 51174-96-0*0 Hypochloroperoxoous acid, hydroxy ester HOOOCl (g, anti) 49.5 42.5 ± 2.5 kJ/mol 84.4588 ± 0.0013 928652-99-7*2 Isocyanogen cation [CNCN]+ (g) 1653.1 1655.4 ± 1.6 kJ/mol 52.0343 ± 0.0016 133415-63-1*0 Dihydrogen H2 (g, para) -0.000 -0.058 ± 0.000 kJ/mol 2.01588 ± 0.00014 1333-74-0*2 Carbon monoxide CO (g, singlet) -113.803 -110.523 ± 0.026 kJ/mol 28.01010 ± 0.00085 630-08-0*2 Tropylide [CH(CHCHCHCHCHCH)]- (g) 260.9 244.6 ± 2.0 kJ/mol 91.1310 ± 0.0056 34464-18-1*0 Bicyclo[1.1.0]buta-1,3-dien-2-yl anion [C(CC)C]- (g) 803.6 811.3 ± 2.1 kJ/mol 48.0433 ± 0.0032 289679-89-6*0 Diisocyanogen cation [CNNC]+ (g, cis) 1838.0 1842.0 ± 3.1 kJ/mol 52.0343 ± 0.0016 *78800-21-2*2 Dihydrogen cation [H2]+ (g, para) 1488.364 1488.480 ± 0.000 kJ/mol 2.01533 ± 0.00014 12184-90-6*2 Iodine I (g, 2P1/2) 198.109 197.709 ± 0.0021 kJ/mol 126.904470 ± 0.000030 14362-44-8*2 Trioxygen difluoride FOOOF (g) 112.2 107.1 ± 1.1 kJ/mol 85.99501 ± 0.00090 16829-28-0*0 Cyclopentadiene CH2(CHCHCHCH) (l) 109.87 ± 0.58 kJ/mol 66.1011 ± 0.0040 542-92-7*590 Trihydrogen (H)(HH) (g, vdW) 215.9 218.3 ± 1.1 kJ/mol 3.02382 ± 0.00021 12184-91-7*100 Acetic acid CH3C(O)OH (aq, 500 H2O) -484.89 ± 0.23 kJ/mol 60.0520 ± 0.0017 64-19-7*833 Hydrogen peroxide H2O2 (g, para) -129.480 -135.466 ± 0.063 kJ/mol 34.01468 ± 0.00062 7722-84-1*2 Acetic acid CH3C(O)OH (aq, 10000 H2O) -484.94 ± 0.23 kJ/mol 60.0520 ± 0.0017 64-19-7*850 1-Hydroxyethyl CH3CHOH (g) -42.74 -56.17 ± 0.58 kJ/mol 45.0605 ± 0.0017 2348-46-1*0 Hydroxymethylene HCOH (g) 112.67 108.91 ± 0.28 kJ/mol 30.02598 ± 0.00087 19710-56-6*0 Deuterium molecule cation [D2]+ (g) 1492.286 1492.361 ± 0.000 kJ/mol 4.02765497609 ± 0.00000000080 12184-84-8*0 Trioxirane cation [O(OO)]+ (g) 1444.5 1442.3 ± 2.2 kJ/mol 47.99765 ± 0.00090 *153851-84-4*0 Oxoniumyl ion [H2O]+ (g, ortho) 978.466 975.562 ± 0.028 kJ/mol 18.01473 ± 0.00033 56583-62-1*1 Ammonium hydroxide NH4OH (aq, undissoc) -366.716 ± 0.062 kJ/mol 35.04584 ± 0.00047 1336-21-6*1000 Hydrazoic acid anion [HNNN]- (g, cis) 316.1 310.0 ± 2.3 kJ/mol 43.02871 ± 0.00022 203264-98-6*2 Difluorine cation [F2]+ (g) 1514.301 1514.475 ± 0.013 kJ/mol 37.9962578 ± 0.0000010 12184-86-0*0 2-Chloro ozone ClO(O)O (g) 265.9 265.3 ± 3.7 kJ/mol 83.4509 ± 0.0013 *141801-66-3*0 Trioxodinitrate anion [ONN(O)O]- (g, non-vdW) -87.3 -93.1 ± 2.2 kJ/mol 76.01223 ± 0.00091 194856-62-7*1 Tribromine cation [Br3]+ (g) 1035.9 1013.2 ± 2.6 kJ/mol 239.7115 ± 0.0030 33105-86-1*0 1-Methylethenylium [CH3CCH2]+ (g) 995.2 986.0 ± 2.0 kJ/mol 41.0713 ± 0.0024 50457-57-3*0 Methyl acetate CH3C(O)OCH3 (g) -394.29 -413.15 ± 0.61 kJ/mol 74.0785 ± 0.0025 79-20-9*0 Fluorine atom F (g, 2P3/2) 77.258 79.043 ± 0.048 kJ/mol 18.99840320 ± 0.00000050 14762-94-8*1 Succinic acid (CH2C(O)OH)2 (cr,l) -918.55 -940.28 ± 0.13 kJ/mol 118.0880 ± 0.0034 110-15-6*500 1,3-Butadiyn-4-ylium-1-yl [CCCC]+ (g) 2109.9 2120.5 ± 2.9 kJ/mol 48.0423 ± 0.0032 124708-46-9*0 1-Methylethenyl anion [CH3CCH2]- (g) 199.4 188.2 ± 2.0 kJ/mol 41.0723 ± 0.0024 65887-19-6*0 2-Hydroxyethylium [CH2CH2OH]+ (g, gauche) 1024.4 1011.9 ± 2.0 kJ/mol 45.0600 ± 0.0017 38607-31-7*1 1,2-Dibromoethane CH2BrCH2Br (cr,l) -80.3 ± 1.2 kJ/mol 187.8612 ± 0.0026 106-93-4*500 Water H2O (g, para) -238.933 -241.836 ± 0.026 kJ/mol 18.01528 ± 0.00033 7732-18-5*2 Acetylene HCCH (g, cis-triplet) 599.1 598.9 ± 1.5 kJ/mol 26.0373 ± 0.0016 74-86-2*11 Dioxofluorine anion [OFO]- (g) 155.9 154.3 ± 2.5 kJ/mol 50.99775 ± 0.00060 *175861-93-5*0 1,2-Propadien-1-ylium-1-yl-3-ylidene [CCC]+ (g) 1944.7 1952.6 ± 1.9 kJ/mol 36.0316 ± 0.0024 118090-85-0*0 Deuteride D- (g) 146.991 148.904 ± 0.0021 kJ/mol 2.01465035791 ± 0.00000000040 14452-69-8*0 Bromodioxy BrOO (g) 118.3 109.2 ± 4.3 kJ/mol 111.9028 ± 0.0012 67177-47-3*0 Oxygen atom heptacation [O]+7 (g) 113369.48 113371.34 ± 0.12 kJ/mol 15.99556 ± 0.00030 14274-89-6*0 1,3-Butadien-2-ol CH2C(OH)CHCH2 (g, s-cis, syn) -43.1 -59.6 ± 2.3 kJ/mol 70.0898 ± 0.0032 59120-04-6*21 1,3-Butadien-2-ol CH2C(OH)CHCH2 (g, s-trans) -53.8 -69.1 ± 1.6 kJ/mol 70.0898 ± 0.0032 59120-04-6*1 Dioxofluorine cation [OFO]+ (g) 1667.0 1664.8 ± 2.8 kJ/mol 50.99665 ± 0.00060 223566-05-0*0 1,3-Butadiynyl anion [CCCC]- (g) 677.7 686.8 ± 1.2 kJ/mol 48.0433 ± 0.0032 59158-53-1*0 Acrolein CH2CHCHO (g) -55.3 -65.4 ± 1.2 kJ/mol 56.0633 ± 0.0024 107-02-8*0 Chlorine atom Cl (g, 2P3/2) 119.621 121.228 ± 0.0011 kJ/mol 35.45270 ± 0.00090 22537-15-1*1 1,2-Propadien-1-one cation [CH2CCO]+ (g) 1012.6 1011.2 ± 1.9 kJ/mol 54.0468 ± 0.0024 87612-93-9*0 2-Propynal cation [CHCCHO]+ (g) 1168.3 1167.2 ± 1.6 kJ/mol 54.0468 ± 0.0024 100815-70-1*0 Dinitrogen dimer (N2)2 (g) -0.88 0.84 ± 0.67 kJ/mol 56.02696 ± 0.00028 154680-01-0*0 Water H2O (cr) -286.302 -292.743 ± 0.026 kJ/mol 18.01528 ± 0.00033 7732-18-5*510 sec-Butylium [CH3CH2CHCH3]+ (g) 792.8 769.2 ± 1.8 kJ/mol 57.1137 ± 0.0033 16548-59-7*0 Trihydrogen cation [H3]+ (g, para) 1110.304 1106.697 ± 0.013 kJ/mol 3.02327 ± 0.00021 28132-48-1*2 Polyoxymethylene CH2O (cr, polyoxymethylene) -170.88 ± 0.21 kJ/mol 30.02598 ± 0.00087 9002-81-7*500 Oxygen atom octacation [O]+8 (g) 197447.75 197449.60 ± 0.12 kJ/mol 15.99501 ± 0.00030 21450-98-6*0 Hydrogen fluoride HF (aq, 45 H2O) -321.15 ± 0.16 kJ/mol 20.006343 ± 0.000070 7664-39-3*906 Hydrazoic acid HNNN (aq, undissoc) 257.58 ± 0.48 kJ/mol 43.02816 ± 0.00022 7782-79-8*1000 mu-Oxodichlorate anion [ClOCl]- (g) -147.8 -147.7 ± 2.5 kJ/mol 86.9053 ± 0.0018 365546-30-1*0 Peroxyhypochlorous acid cation [HOOCl]+ (g, cis) 1050.8 1045.1 ± 2.5 kJ/mol 68.4589 ± 0.0011 *67952-07-2*2 Tribromide [Br3]- (aq) -129.51 ± 0.25 kJ/mol 239.7125 ± 0.0030 14522-80-6*800 Formaldehyde CH2O (aq) -171.19 ± 0.59 kJ/mol 30.02598 ± 0.00087 50-00-0*800 Hydroxylamine NH2OH (cr,l) -107.61 ± 0.63 kJ/mol 33.02996 ± 0.00037 7803-49-8*500 3-Imino-2-propen-1-ylidene CHCHCNH (g, singlet) 530.6 526.3 ± 1.2 kJ/mol 53.0627 ± 0.0024 916765-05-4*1 Tetroxidane HOOOOH (g) -34.2 -44.6 ± 2.4 kJ/mol 66.0135 ± 0.0012 29683-94-1*0 2-(Methylidyneamino)ethenyl CHCHNCH (g, singlet) 600.6 596.3 ± 1.2 kJ/mol 53.0627 ± 0.0024 123416-74-0*1 Oxygen atom dication [O]+2 (g) 4949.459 4953.000 ± 0.013 kJ/mol 15.99830 ± 0.00030 14127-63-0*0 Ethynylene C2 (g, singlet) 820.28 826.85 ± 0.26 kJ/mol 24.0214 ± 0.0016 12070-15-4*2 Methyl formate HC(O)OCH3 (g) -346.86 -359.90 ± 0.84 kJ/mol 60.0520 ± 0.0017 107-31-3*0 Ethynylene C2 (g, triplet) 827.50 834.21 ± 0.26 kJ/mol 24.0214 ± 0.0016 12070-15-4*1 Propylene cation [CH3CHCH2]+ (g) 975.21 961.68 ± 0.21 kJ/mol 42.0792 ± 0.0024 34504-10-4*0 Nitrosyl nitrite anion [ONONO]- (g, t, c) -100.3 -103.5 ± 2.9 kJ/mol 76.01223 ± 0.00091 *122413-35-8*2 Peroxyhypochlorous acid anion [HOOCl]- (g, trans quartet) -2.9 -3.3 ± 2.6 kJ/mol 68.4600 ± 0.0011 *67952-08-3*1 Tetraoxygen O4 (g, D2h singlet) 69.8 65.1 ± 4.4 kJ/mol 63.9976 ± 0.0012 12596-83-7*21 Oxygen atom tetracation [O]+4 (g) 17719.207 17721.064 ± 0.025 kJ/mol 15.99721 ± 0.00030 14127-65-2*0 Peroxyformate [HC(O)OO]- (g, anti) -320.7 -326.5 ± 1.8 kJ/mol 61.0174 ± 0.0012 104960-05-6*2 Tetraoxygen O4 (g, D2d singlet) 399.0 393.2 ± 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 Fluorosyl fluoride anion [FFO]- (g) -147.2 -146.9 ± 3.0 kJ/mol 53.99675 ± 0.00030 *86825-57-2*0 Chlorovinylidene CCHCl (g) 428.1 429.8 ± 3.0 kJ/mol 60.4820 ± 0.0018 70277-82-6*0 Methoxyoxomethyl CH3OCO (g, syn-staggered) -151.7 -160.7 ± 2.2 kJ/mol 59.0440 ± 0.0017 16481-04-2*2 Fluorosyl fluoride cation [FFO]+ (g) 1413.0 1413.4 ± 3.5 kJ/mol 53.99566 ± 0.00030 *86825-50-5*0 Chlorohydroxymethylene ClCOH (g, cis) 14.3 11.4 ± 3.2 kJ/mol 64.4707 ± 0.0012 147723-60-2*2 Chlorohydroxymethylene ClCOH (g) 13.9 11.2 ± 2.6 kJ/mol 64.4707 ± 0.0012 147723-60-2*0 1-Methylethylidene CH3CCH3 (g) 316.2 303.3 ± 2.0 kJ/mol 42.0797 ± 0.0024 40852-89-9*0 (Chlorooxy)methylene HCOCl (g, trans) 155.4 155.2 ± 3.7 kJ/mol 64.4707 ± 0.0012 331419-80-8*1 (Chlorooxy)methylene HCOCl (g) 119.1 117.8 ± 2.7 kJ/mol 64.4707 ± 0.0012 331419-80-8*0 Chlorous acid cation [HOClO]+ (g) 996.6 991.5 ± 3.1 kJ/mol 68.4589 ± 0.0011 *99559-66-7*0 Dioxoethylium [OCHCO]+ (g) 688.2 689.5 ± 3.1 kJ/mol 57.0276 ± 0.0017 *1994332-01-2*0 Chloroformyl anion [ClCO]- (g) -356.5 -352.9 ± 3.3 kJ/mol 63.4633 ± 0.0012 41976-93-6*0 Ethylene anion [CH2CH2]- (g) 232.0 225.6 ± 2.0 kJ/mol 28.0537 ± 0.0016 34527-91-8*0 Chlorine trifluoride anion [FCl(F)F]- (g) -480.4 -481.9 ± 3.6 kJ/mol 92.44846 ± 0.00090 184289-50-7*0 Propynylidene HCCCH (g, singlet) 597.6 599.4 ± 1.3 kJ/mol 38.0480 ± 0.0024 67152-18-5*2 Ethanedial anion [OCHCO]- (g) -189.1 -190.6 ± 3.3 kJ/mol 57.0287 ± 0.0017 1994332-01-2*0 Cyanogen chloride cation [ClCN]+ (g) 1326.03 1327.36 ± 0.97 kJ/mol 61.4696 ± 0.0012 37612-72-9*0 Trioxygen difluoride FOOOF (g, cis) 113.4 107.6 ± 2.1 kJ/mol 85.99501 ± 0.00090 16829-28-0*2 Carbon atom C (diamond) 2.391 1.863 ± 0.044 kJ/mol 12.01070 ± 0.00080 7440-44-0*501 Hydroxyoxoethenylium [HOCCO]+ (g) 866.3 865.0 ± 3.6 kJ/mol 57.0276 ± 0.0017 *1994332-00-1*0 2-Iodoethanol ICH2CH2OH (g) -132.0 -150.2 ± 2.5 kJ/mol 171.9650 ± 0.0017 624-76-0*0 Nitrogen atom anion N- (g) 487.6 489.9 ± 2.5 kJ/mol 14.007289 ± 0.000070 17778-87-9*0 Ethynediolide [HOCCO]- (g) -133.1 -134.2 ± 3.5 kJ/mol 57.0287 ± 0.0017 1994332-00-1*0 Oxoethylidene HCC(O)H (g) 261.2 258.4 ± 1.6 kJ/mol 42.0367 ± 0.0016 39920-84-8*0 Fluorosyl fluoride FFO (g) 192.6 193.1 ± 2.3 kJ/mol 53.99621 ± 0.00030 86825-57-2*0 Fluoromethane cation [CH3F]+ (g) 981.80 974.30 ± 0.62 kJ/mol 34.03237 ± 0.00083 59122-96-2*0 Fluoromethane CH3F (l) -245.76 ± 0.45 kJ/mol 34.03292 ± 0.00083 593-53-3*590 2-Oxo-1-ethylium-1-yl [HCC(O)H]+ (g, quartet) 1289.5 1286.8 ± 2.7 kJ/mol 42.0361 ± 0.0016 214464-96-7*1 Cyanomethylium [CH2CN]+ (g) 1256.70 1254.06 ± 0.82 kJ/mol 40.0435 ± 0.0016 34430-18-7*0 Dioxyamidogen HNOO (g, trans) 251.1 244.5 ± 2.5 kJ/mol 47.01348 ± 0.00061 71843-95-3*1 Propargylenide [HCCCH]- (g) 434.4 437.6 ± 1.1 kJ/mol 38.0485 ± 0.0024 82906-05-6*0 Isocyanic acid anion [HNCO]- (g) -54.3 -57.5 ± 3.0 kJ/mol 43.02533 ± 0.00086 *444010-28-0*0 O--HH Complex (H2)(O) (g, vdW Cinfv ?) 247.6 248.9 ± 2.7 kJ/mol 18.01528 ± 0.00033 *7732-18-5*101 Oxoethylidene anion [HCC(O)H]- (g) 87.0 84.3 ± 2.3 kJ/mol 42.0372 ± 0.0016 106543-38-8*0 Peroxychlorous acid HOOClO (g) 96.2 90.6 ± 2.1 kJ/mol 84.4588 ± 0.0013 177778-92-6*0 Hydroxymethylene cation [HCOH]+ (g) 971.9 968.3 ± 1.4 kJ/mol 30.02543 ± 0.00087 135395-06-1*0 Peroxyformyl HC(O)OO (g) -100.42 -105.52 ± 0.93 kJ/mol 61.0168 ± 0.0012 56240-83-6*0 COC vdW (CO)(C) (g) 589.7 598.5 ± 1.6 kJ/mol 40.0208 ± 0.0016 *12071-24-8*0 (Methylamino)methyl anion [CH3NHCH2]- (g) 201.0 184.1 ± 3.2 kJ/mol 44.0763 ± 0.0017 *31277-25-5*0 Chloromethane CH3Cl (l) -106.42 -102.45 ± 0.19 kJ/mol 50.4872 ± 0.0012 74-87-3*590 Hydroperoxonium [H2OOH]+ (g, cis) 762.5 752.7 ± 2.0 kJ/mol 35.02207 ± 0.00064 70850-26-9*2 Methyl bromide cation [CH3Br]+ (g) 996.25 981.34 ± 0.18 kJ/mol 94.9380 ± 0.0013 12538-70-4*0 Propylidene anion [CH3CH2CH]- (g) 300.8 286.6 ± 3.3 kJ/mol 42.0803 ± 0.0024 *121408-55-7*0 Methylaminyliumyl [CH3N]+ (g, quartet) 1423.2 1416.3 ± 2.6 kJ/mol 29.04071 ± 0.00083 56924-51-7*2 Peroxychlorous acid HOOClO (g, perp ?) 102.3 96.2 ± 3.7 kJ/mol 84.4588 ± 0.0013 177778-92-6*3 Methyl iodide cation [CH3I]+ (g) 944.79 935.39 ± 0.18 kJ/mol 141.93844 ± 0.00083 12538-72-6*0 Peroxyhypochlorous acid cation [HOOCl]+ (g) 1030.3 1024.5 ± 2.5 kJ/mol 68.4589 ± 0.0011 *67952-07-2*0 Cyanogen chloride anion [ClCN]- (g) 46.7 51.0 ± 3.1 kJ/mol 61.4707 ± 0.0012 12281-43-5*0 Fluoroform CHF3 (l) -704.44 ± 0.43 kJ/mol 70.01385 ± 0.00080 75-46-7*590 Methoxyoxomethyl CH3OCO (g, anti-eclipsed) -151.6 -159.7 ± 2.2 kJ/mol 59.0440 ± 0.0017 16481-04-2*3 Methanediol CH2(OH)2 (g) -379.37 -392.76 ± 0.93 kJ/mol 48.0413 ± 0.0010 463-57-0*0 Ethane anion [CH3CH3]- (g) 41.9 26.6 ± 4.4 kJ/mol 30.0696 ± 0.0017 54064-82-3*0 Oxonium [H3O]+ (aq) -285.830 ± 0.026 kJ/mol 19.02267 ± 0.00037 13968-08-6*800 Isocyanogen chloride cation [ClNC]+ (g) 1480.8 1482.0 ± 3.9 kJ/mol 61.4696 ± 0.0012 956475-91-5*0 (Dimethylamino)methyl anion [(CH3)2NCH2]- (g) 189.8 165.6 ± 3.3 kJ/mol 58.1029 ± 0.0025 125231-49-4*0 Ethenol CH2CHOH (g) -112.77 -123.20 ± 0.66 kJ/mol 44.0526 ± 0.0017 557-75-5*0 Diazene cation [HNNH]+ (g, trans-cis equilib) 1132.46 1125.53 ± 0.66 kJ/mol 30.02881 ± 0.00020 76986-17-9*1 Iminomethyl HCNH (g) 275.82 272.22 ± 0.71 kJ/mol 28.03332 ± 0.00082 15691-95-9*0 Cyanogen NCCN (cr,l) 273.91 289.16 ± 0.43 kJ/mol 52.0349 ± 0.0016 460-19-5*500 Cyclopentadienide [CH(CHCHCHCH)]- (g) 100.1 87.1 ± 1.1 kJ/mol 65.0937 ± 0.0040 12127-83-2*0 Nitrato [ON(O)O]+ (g) 1290.61 1285.90 ± 0.86 kJ/mol 62.00439 ± 0.00090 133057-96-2*0 Diazanide [NH2NH]- (g) 249.4 239.3 ± 3.1 kJ/mol 31.03785 ± 0.00025 25415-88-7*0 Vinyl alcohol cation [CH2CHOH]+ (g) 778.9 767.9 ± 1.3 kJ/mol 44.0520 ± 0.0017 57239-63-1*0 Isocyanogen chloride anion [ClNC]- (g) 102.8 107.2 ± 3.9 kJ/mol 61.4707 ± 0.0012 923019-39-0*0 trans-Cycloheptene CH2(CHCHCH2CH2CH2CH2 (g) 141.6 103.5 ± 1.9 kJ/mol 96.1702 ± 0.0057 45509-99-7*0 Isocyanogen anion [CNCN]- (g) 385.5 387.6 ± 3.4 kJ/mol 52.0354 ± 0.0016 *83951-85-3*0 Imidogen NH (g, triplet) 358.74 358.78 ± 0.17 kJ/mol 15.014680 ± 0.000099 13774-92-0*1 Trioxodinitrate anion [ONN(O)O]- (g) -104.3 -107.5 ± 1.9 kJ/mol 76.01223 ± 0.00091 194856-62-7*0 Bromoform CHBr3 (l) 2.8 ± 1.2 kJ/mol 252.7306 ± 0.0031 75-25-2*590 Acetyloxoniumylidene [CH3C(O)O]+ (g, triplet) 891.7 883.3 ± 3.0 kJ/mol 59.0435 ± 0.0017 67057-47-0*1 Cyanogen bromide cation [BrCN]+ (g) 1331.2 1324.9 ± 1.1 kJ/mol 105.9209 ± 0.0013 34749-77-4*0 Nitrogen atom N (g, doublet) 700.554 702.457 ± 0.024 kJ/mol 14.006740 ± 0.000070 17778-88-0*2 Isocyanic fluoride cation [FNC]+ (g) 1618.4 1619.0 ± 4.0 kJ/mol 45.01529 ± 0.00080 *16992-26-0*0 Difluoromethane CH2F2 (l) -468.68 ± 0.36 kJ/mol 52.02339 ± 0.00081 75-10-5*590 Diisocyanogen anion [CNNC]- (g) 456.3 461.9 ± 3.7 kJ/mol 52.0354 ± 0.0016 *78800-22-3*0 Diisocyanogen cation [CNNC]+ (g) 1824.8 1827.9 ± 3.3 kJ/mol 52.0343 ± 0.0016 *78800-21-2*0 Peroxyhypochlorous acid anion [HOOCl]- (g, quartet) -32.2 -34.0 ± 2.6 kJ/mol 68.4600 ± 0.0011 *67952-08-3*0 Phenol cation [C6H5OH]+ (g) 746.18 727.39 ± 0.65 kJ/mol 94.1107 ± 0.0048 40932-22-7*0 Phenol anion [C6H5OH]- (g) 22.8 7.8 ± 4.9 kJ/mol 94.1118 ± 0.0048 38752-11-3*0 Dinitrogen tetraoxide O2NNO2 (cr,l) -37.87 -27.02 ± 0.19 kJ/mol 92.0111 ± 0.0012 10544-72-6*500 Diazene anion [HNNH]- (g, trans-cis-iso equilib) 265.5 258.7 ± 2.0 kJ/mol 30.02991 ± 0.00020 100429-75-2*0 Hydrogen peroxide cation [H2O2]+ (g, trans, para) 897.25 890.25 ± 0.51 kJ/mol 34.01413 ± 0.00062 12325-10-9*12 Formic acid cation [HC(O)OH]+ (g) 721.87 715.34 ± 0.26 kJ/mol 46.0248 ± 0.0010 50614-05-6*0 Diazoethenylidene cation [NNCC]+ (g) 1771.2 1773.2 ± 3.5 kJ/mol 52.0343 ± 0.0016 *130760-10-0*0 Difluorodioxidane anion [FOOF]- (g) -251. -251. ± 28. kJ/mol 69.99615 ± 0.00060 *7783-45-1*0 Benzaldehyde cation [C6H5C(O)H]+ (g) 896.8 880.1 ± 1.9 kJ/mol 106.1214 ± 0.0056 80226-59-1*0 Benzaldehyde anion [C6H5C(O)H]- (g) -60.2 -77.9 ± 1.2 kJ/mol 106.1225 ± 0.0056 34473-57-9*0 Diazoethenylidene anion [NNCC]- (g) 529.7 532.3 ± 3.5 kJ/mol 52.0354 ± 0.0016 *130760-11-1*0 Formic acid anion [HC(O)OH]- (g) -256.2 -262.3 ± 1.8 kJ/mol 46.0259 ± 0.0010 19066-82-1*0 3H-diazirin-3-ylidene-methylene CC(NN) (g) 837.3 839.9 ± 2.4 kJ/mol 52.0349 ± 0.0016 204253-88-3*0 Imidogen NH (g, singlet) 509.33 509.38 ± 0.18 kJ/mol 15.014680 ± 0.000099 13774-92-0*2 1,2-Butadiene CH3CHCCH2 (cr,l) 137.56 138.61 ± 0.68 kJ/mol 54.0904 ± 0.0032 590-19-2*500 Nitrosodioxaziridine ONN(OO) (g, gauche) 415.3 409.5 ± 2.8 kJ/mol 76.01168 ± 0.00091 132871-99-9*3 Oxide [O]-2 (g) 651. 653. ± 15. kJ/mol 16.00050 ± 0.00030 16833-27-5*0 Diazene anion [HNNH]- (g, trans-cis equilib) 265.5 258.7 ± 2.0 kJ/mol 30.02991 ± 0.00020 100429-75-2*1 Dioxodiazoxane ONONO (g) 93.0 88.1 ± 1.3 kJ/mol 76.01168 ± 0.00091 122413-35-8*0 Dichlorine cation [Cl2]+ (g) 1108.287 1108.266 ± 0.013 kJ/mol 70.9049 ± 0.0018 12595-90-3*0 Ethylidene CH3CH (g) 361.30 354.31 ± 0.75 kJ/mol 28.0532 ± 0.0016 4218-50-2*0 Diazene cation [HNNH]+ (g, trans-iso-cis equilib) 1132.46 1125.81 ± 0.66 kJ/mol 30.02881 ± 0.00020 76986-17-9*0 Water H2O (cr, eq.press.) -286.304 -292.745 ± 0.026 kJ/mol 18.01528 ± 0.00033 7732-18-5*509 2-Hydroxyethyl CH2CH2OH (g) -13.34 -26.60 ± 0.56 kJ/mol 45.0605 ± 0.0017 4422-54-2*0 Water anion [H2O]- (g) -50.1 -53.0 ± 4.3 kJ/mol 18.01583 ± 0.00033 12259-30-2*0 Difluorodioxidanium [FOOF]+ (g) 1283.6 1280.0 ± 2.3 kJ/mol 69.99506 ± 0.00060 *7783-44-0*0 Hydrazoic acid HNNN (cr,l) 261.44 ± 0.65 kJ/mol 43.02816 ± 0.00022 7782-79-8*500 Aminomethylidyne anion [CNH2]- (g, triplet) 481.6 478.0 ± 3.2 kJ/mol 28.03387 ± 0.00082 96808-04-7*1 C=O-C cation [COC]+ (g) 1585.8 1592.9 ± 2.7 kJ/mol 40.0203 ± 0.0016 83483-98-1*0 Nitrogen sesquioxide cation [ONN(O)O]+ (g, vdW) 1027.6 1023.7 ± 4.8 kJ/mol 76.01113 ± 0.00091 *10544-73-7*0 Cyanic acid cation [HOCN]+ (g) 1135.7 1133.2 ± 2.9 kJ/mol 43.02423 ± 0.00086 59780-31-3*0 Propylidyne CH3CH2C (g) 492.4 482.8 ± 1.2 kJ/mol 41.0718 ± 0.0024 85056-54-8*0 Chlorine pentafluoride cation [FCl(F)(F)(F)F]+ (g) 1005.8 996.8 ± 3.3 kJ/mol 130.44417 ± 0.00090 478167-78-1*0 Oxiranylium [CH2(CHO)]+ (g) 901.1 893.2 ± 1.5 kJ/mol 43.0441 ± 0.0016 57789-76-1*0 Pentachloroethylium [CCl3CCl2]+ (g) 836.1 834.5 ± 3.3 kJ/mol 201.2844 ± 0.0048 *7094-17-9*0 Oxiranyl anion [CH2(CHO)]- (g) 121.1 113.2 ± 1.6 kJ/mol 43.0452 ± 0.0016 72722-59-9*0 Hydrogen isocyanide anion [HNC]- (g) 191.44 191.62 ± 0.36 kJ/mol 27.02593 ± 0.00081 96913-22-3*0 Pentachloroethanide [CCl3CCl2]- (g) -283.7 -282.3 ± 3.9 kJ/mol 201.2854 ± 0.0048 263019-83-6*0 Acetone enol CH3C(OH)CH2 (g) -151.8 -168.7 ± 1.1 kJ/mol 58.0791 ± 0.0025 29456-04-0*0 Nitrosyl nitrite anion [ONONO]- (g) -103.1 -106.2 ± 2.8 kJ/mol 76.01223 ± 0.00091 *122413-35-8*0 Hydrogen peroxide cation [H2O2]+ (g) 897.23 890.25 ± 0.51 kJ/mol 34.01413 ± 0.00062 12325-10-9*0 Trihydrogen HHH (g, TS) 254.5 250.7 ± 1.2 kJ/mol 3.02382 ± 0.00021 12184-91-7*200 Nitrosodioxaziridine ONN(OO) (g) 413.6 408.2 ± 1.8 kJ/mol 76.01168 ± 0.00091 132871-99-9*0 Hydroxyformyl HOCO (g) -181.09 -183.64 ± 0.46 kJ/mol 45.0174 ± 0.0010 2564-86-5*0 1-Propen-1-yl-3-ylidene CHCHCH (g, c-t quartet) 657.4 653.8 ± 2.2 kJ/mol 39.0559 ± 0.0024 84654-90-0*12 Cyclopropane CH2(CH2CH2) (l) 41.41 35.73 ± 0.54 kJ/mol 42.0797 ± 0.0024 75-19-4*500 Chlorine chlorite ClOClO (g) 168.6 166.4 ± 1.3 kJ/mol 102.9042 ± 0.0019 105206-44-8*0 Hydroxyaminylium [HNOH]+ (g) 1019.6 1012.4 ± 2.5 kJ/mol 32.02147 ± 0.00034 66097-71-0*0 Methyl nitrite CH3ONO (g, trans) -52.54 -64.50 ± 0.90 kJ/mol 61.0401 ± 0.0010 624-91-9*1 Methyl nitrite CH3ONO (cr,l) -88.89 ± 0.56 kJ/mol 61.0401 ± 0.0010 624-91-9*500 1,2-Dibromoethene CHBrCHBr (g) 120.9 100.8 ± 2.1 kJ/mol 185.8453 ± 0.0026 540-49-8*0 Hydroperoxonium [H2OOH]+ (g) 738.1 727.8 ± 1.2 kJ/mol 35.02207 ± 0.00064 70850-26-9*0 Hydroxyformyl anion [HOCO]- (g) -319.46 -321.32 ± 0.59 kJ/mol 45.0180 ± 0.0010 78944-70-4*0 Oxirene O(CHCH) (g) 273.18 271.02 ± 0.92 kJ/mol 42.0367 ± 0.0016 157-18-6*0 Oxirene O(CHCH) (g, triplet) 387.9 384.5 ± 1.4 kJ/mol 42.0367 ± 0.0016 157-18-6*1 2,2,4-Trimethylpentane (CH3)2CHCH2C(CH3)3 (g) -171.3 -223.7 ± 1.5 kJ/mol 114.2285 ± 0.0065 540-84-1*0 Hydrazine anion [NH2NH2]- (g) 232.2 217.8 ± 4.1 kJ/mol 32.04579 ± 0.00031 65391-88-0*0 Nitrous acid anion [HONO]- (g) -105.85 -109.33 ± 0.78 kJ/mol 47.01403 ± 0.00061 256393-36-9*0 Cyanic acid anion [HOCN]- (g) -9.2 -9.5 ± 3.1 kJ/mol 43.02533 ± 0.00086 58199-47-6*0 (Formyloxy)methyl HC(O)OCH2 (g) -151.9 -160.0 ± 1.3 kJ/mol 59.0440 ± 0.0017 3122-12-1*0 Trihydrogen H(HH) (g, TS) 477.4 474.7 ± 2.3 kJ/mol 3.02382 ± 0.00021 12184-91-7*201 Carboxymethyl CH2C(O)OH (g) -227.4 -237.3 ± 1.2 kJ/mol 59.0440 ± 0.0017 2887-46-9*0 Ethynol cation [HCCOH]+ (g) 1064.0 1061.4 ± 3.0 kJ/mol 42.0361 ± 0.0016 84005-02-7*0 Trioxidaniumyl [HOOOH]+ (g) 925.4 916.5 ± 1.5 kJ/mol 50.01353 ± 0.00091 161321-37-5*0 1-Propen-1-yl-3-ylidene CHCHCH (g, t-t quartet) 666.4 662.9 ± 2.2 kJ/mol 39.0559 ± 0.0024 84654-90-0*13 Perchloric acid cation [HOCl(O)(O)O]+ (g) 1191.8 1182.2 ± 3.5 kJ/mol 100.4577 ± 0.0015 91712-47-9*0 Chlorine pentafluoride anion [FCl(F)(F)(F)F]- (g) -619.3 -622.7 ± 4.4 kJ/mol 130.44526 ± 0.00090 184851-42-1*0 Oxoniumyl ion [H2O]+ (g, para) 978.716 975.565 ± 0.028 kJ/mol 18.01473 ± 0.00033 56583-62-1*2 1,1-Dibromoethane CH3CHBr2 (cr,l) -67.3 ± 1.3 kJ/mol 187.8612 ± 0.0026 557-91-5*500 1-Propen-1-yl-3-ylidene CHCHCH (g, doublet) 699.9 697.0 ± 3.5 kJ/mol 39.0559 ± 0.0024 84654-90-0*2 Isofulminic acid cation [HONC]+ (g) 1377.0 1374.9 ± 2.9 kJ/mol 43.02423 ± 0.00086 117800-60-9*0 2-Methoxy-2-oxoethyl CH2C(O)OCH3 (g) -203.4 -218.6 ± 1.6 kJ/mol 73.0706 ± 0.0025 54668-31-4*0 Ethynol anion [HCCOH]- (g) 163.7 165.2 ± 3.4 kJ/mol 42.0372 ± 0.0016 864971-50-6*0 Isocyanogen bromide cation [BrNC]+ (g) 1469.9 1464.1 ± 5.9 kJ/mol 105.9209 ± 0.0013 238754-53-5*0 Hydrogen peroxide H2O2 (g, ortho) -129.459 -135.466 ± 0.063 kJ/mol 34.01468 ± 0.00062 7722-84-1*1 Ethynol HCCOH (g) 95.47 92.99 ± 0.94 kJ/mol 42.0367 ± 0.0016 32038-79-2*0 Methane anion [CH4]- (g) 27.3 19.4 ± 5.1 kJ/mol 16.04301 ± 0.00085 27680-53-1*0 Dinitrogen anion [N2]- (g) 192.5 192.5 ± 1.7 kJ/mol 28.01403 ± 0.00014 12185-02-3*0 Formylimidogen HC(O)N (g, triplet) 245.2 242.1 ± 4.6 kJ/mol 43.02478 ± 0.00086 42288-92-6*1 Iminomethyl anion [HCNH]- (g) 237.4 233.6 ± 1.8 kJ/mol 28.03387 ± 0.00082 90623-30-6*0 Hydrogen cyanide anion [HCN]- (g) 129.511 129.033 ± 0.090 kJ/mol 27.02593 ± 0.00081 12334-27-9*0 Krypton dication [Kr]+2 (g) 3701.124 3701.124 ± 0.013 kJ/mol 83.7989 ± 0.1000 18469-91-5*0 Hydrodioxonitrogen cation [HN(O)O]+ (g) 1129.7 1123.0 ± 3.2 kJ/mol 47.01293 ± 0.00061 252986-76-8*0 Xenon dication [Xe]+2 (g) 3194.14 3194.14 ± 0.36 kJ/mol 131.2889 ± 0.0200 14066-95-6*0 Ethynol HCCOH (g, t-c triplet) 406.5 403.3 ± 3.2 kJ/mol 42.0367 ± 0.0016 32038-79-2*12 mu-Oxodioxodinitrogen [ONONO]+ (g, t, t) 984.0 981.0 ± 3.2 kJ/mol 76.01113 ± 0.00091 87950-63-8*1 Oxonium [H3O]+ (g, ortho) 605.90 599.09 ± 0.17 kJ/mol 19.02267 ± 0.00037 13968-08-6*1 3-Buten-2-one CH3C(O)CHCH2 (g) -95.56 -111.10 ± 0.87 kJ/mol 70.0898 ± 0.0032 78-94-4*0 Isocyanic fluoride anion [FNC]- (g) 74.3 76.0 ± 5.7 kJ/mol 45.01639 ± 0.00080 357426-78-9*0 3-Buten-2-one CH3C(O)CHCH2 (g, cis) -94.0 -110.0 ± 1.6 kJ/mol 70.0898 ± 0.0032 78-94-4*2 1-Propen-1-yl-3-ylidene CHCHCH (g) 657.4 654.0 ± 1.5 kJ/mol 39.0559 ± 0.0024 84654-90-0*0 1,3-Butadien-2-ol CH2C(OH)CHCH2 (g, s-trans, anti) -48.4 -64.7 ± 2.3 kJ/mol 70.0898 ± 0.0032 59120-04-6*12 (Acetyloxy)methyl CH3C(O)OCH2 (g) -200.7 -214.5 ± 1.6 kJ/mol 73.0706 ± 0.0025 2887-49-2*0 1,3-Butadien-2-ol CH2C(OH)CHCH2 (g, s-cis, anti) -38.3 -54.7 ± 2.3 kJ/mol 70.0898 ± 0.0032 59120-04-6*22 Hydrodioxonitrate [HN(O)O]- (g) -62.3 -68.8 ± 3.3 kJ/mol 47.01403 ± 0.00061 61508-71-2*0 1,3-Butadien-2-ol CH2C(OH)CHCH2 (g, s-cis) -43.1 -59.1 ± 2.3 kJ/mol 70.0898 ± 0.0032 59120-04-6*2 1,3-Butadien-2-ol CH2C(OH)CHCH2 (g) -53.8 -68.7 ± 1.6 kJ/mol 70.0898 ± 0.0032 59120-04-6*0 1,2-Dichloroethene CHClCHCl (g) 3.46 -1.86 ± 0.54 kJ/mol 96.9427 ± 0.0024 540-59-0*0 1,2-Difluoroethene CHFCHF (g) -302.90 -308.99 ± 0.90 kJ/mol 64.0341 ± 0.0016 1691-13-0*0 Dioxymethylene HCOO (g) 341.8 339.8 ± 3.0 kJ/mol 45.0174 ± 0.0010 438586-67-5*0 Ethynol HCCOH (g, t-t triplet) 409.5 406.4 ± 3.2 kJ/mol 42.0367 ± 0.0016 32038-79-2*13 Ethynol HCCOH (g, c-t triplet) 455.6 452.3 ± 3.2 kJ/mol 42.0367 ± 0.0016 32038-79-2*14 Isoformyl anion [COH]- (g) 55.7 58.4 ± 1.8 kJ/mol 29.01859 ± 0.00086 81747-63-9*0 Hydrogen peroxide cation [H2O2]+ (g, cis, ortho) 931.00 924.12 ± 0.98 kJ/mol 34.01413 ± 0.00062 12325-10-9*21 1,2-Propadien-1-one anion [CH2CCO]- (g) 49.5 48.3 ± 3.1 kJ/mol 54.0479 ± 0.0024 159171-62-7*0 Diiodine cation [I2]+ (g) 963.523 960.408 ± 0.018 kJ/mol 253.808391 ± 0.000060 28712-14-3*0 Carbonylmethyloxonium [CH3OCO]+ (g) 561.5 553.2 ± 3.2 kJ/mol 59.0435 ± 0.0017 24434-00-2*0 Hydroxyamidogen HNOH (g) 101.5 94.7 ± 1.1 kJ/mol 32.02202 ± 0.00034 13940-32-4*0 2-Cyclopropen-1-one cation [OC(CHCH)]+ (g) 1078.5 1075.4 ± 2.0 kJ/mol 54.0468 ± 0.0024 100815-68-7*0 Cyanic fluoride cation [FCN]+ (g) 1294.5 1294.9 ± 1.1 kJ/mol 45.01529 ± 0.00080 62532-69-8*0 Dichloromethylene CCl2 (g) 229.51 230.69 ± 0.64 kJ/mol 82.9161 ± 0.0020 1605-72-7*0 Difluorovinylidene anion [CCF2]- (g) -88.2 -87.1 ± 2.3 kJ/mol 62.0188 ± 0.0016 107693-92-5*0 Methylaminyliumyl [CH3N]+ (g ?) 1388.4 1382.1 ± 2.6 kJ/mol 29.04071 ± 0.00083 56924-51-7*0 2-Hydroxyethylium [CH2CH2OH]+ (g) 1019.0 1006.9 ± 1.5 kJ/mol 45.0600 ± 0.0017 38607-31-7*0 Isourea NHC(OH)NH2 (g) -156.2 -172.8 ± 2.6 kJ/mol 60.05534 ± 0.00091 4744-36-9*0 Ethynol HCCOH (g, c-c triplet) 464.2 461.0 ± 3.2 kJ/mol 42.0367 ± 0.0016 32038-79-2*15 Dibromovinylidene CCBr2 (g) 510.0 498.9 ± 4.1 kJ/mol 183.8294 ± 0.0026 261771-36-2*0 Carbamoyl anion [NH2CO]- (g) -81.7 -87.6 ± 3.1 kJ/mol 44.03327 ± 0.00087 78944-69-1*0 Iodine monochloride ICl (cr,l) -36.511 -35.537 ± 0.063 kJ/mol 162.35717 ± 0.00090 7790-99-0*500 Cyanic fluoride anion [FCN]- (g) -20.4 -18.4 ± 2.9 kJ/mol 45.01639 ± 0.00080 34507-50-1*0 Peroxyformate [HC(O)OO]- (g) -340.96 -346.40 ± 0.96 kJ/mol 61.0174 ± 0.0012 104960-05-6*0 Fluorovinylidene CCHF (g) 298.9 300.1 ± 3.1 kJ/mol 44.0277 ± 0.0016 70302-00-0*0 Formaldoxime CH2NOH (g) 30.7 20.1 ± 1.4 kJ/mol 45.04066 ± 0.00088 75-17-2*0 Methoxyoxomethyl CH3OCO (g) -152.5 -160.1 ± 1.5 kJ/mol 59.0440 ± 0.0017 16481-04-2*0 Trihydrogen H(HH) (g, Ry) 745.878 743.199 ± 0.062 kJ/mol 3.02382 ± 0.00021 12184-91-7*0 Tetraoxidanyl HOOOO (g, trans) 76.7 69.5 ± 6.1 kJ/mol 65.0055 ± 0.0012 69696-93-1*1 Dicarbon monoxide CCO (g) 377.13 381.17 ± 0.98 kJ/mol 40.0208 ± 0.0016 12071-23-7*0 2-Cyclopropyn-1-ylidene C(CC) (g) 898.9 905.8 ± 1.6 kJ/mol 36.0321 ± 0.0024 102508-15-6*0 Chlorous acid anion [HOClO]- (g) -154.3 -156.2 ± 3.3 kJ/mol 68.4600 ± 0.0011 99559-66-7*0 Dioxohydrazine ONNO (g, trans) 192.2 188.6 ± 1.8 kJ/mol 60.01228 ± 0.00062 16824-89-8*1 Hypochloroperoxoous acid, hydroxy ester HOOOCl (g) 49.1 42.3 ± 1.9 kJ/mol 84.4588 ± 0.0013 928652-99-7*0 1,2-Propadien-1-yl-3-ylidene anion [CCC]- (g, lin) 622.0 629.4 ± 1.3 kJ/mol 36.0326 ± 0.0024 109292-47-9*1 Water dimer cation [(H2O)2]+ (g) 556.8 546.4 ± 3.0 kJ/mol 36.03001 ± 0.00066 158061-35-9*0 Oxoiodonium [IO]+ (g) 1066.1 1064.1 ± 1.9 kJ/mol 142.90332 ± 0.00030 81182-81-2*0 Chlorine atom Cl (g, 2P1/2) 130.176 131.783 ± 0.0011 kJ/mol 35.45270 ± 0.00090 22537-15-1*2 1-Methoxyethenol CH2C(OH)OCH3 (g) -284.8 -303.3 ± 1.7 kJ/mol 74.0785 ± 0.0025 4453-91-2*0 Bromovinylidene CCHBr (g) 466.1 460.1 ± 3.8 kJ/mol 104.9333 ± 0.0019 161957-27-3*0 Fluorine atom F (g, 2P1/2) 82.093 83.878 ± 0.048 kJ/mol 18.99840320 ± 0.00000050 14762-94-8*2 Tetraoxidanyl HOOOO (g) 2.0 0.2 ± 3.0 kJ/mol 65.0055 ± 0.0012 69696-93-1*0 1-Cyanoethylidene CH3CCN (g) 437.6 433.9 ± 1.5 kJ/mol 53.0627 ± 0.0024 498544-34-6*0 Difluorophosgene anion [CF2O]- (g) -602.3 -604.2 ± 3.3 kJ/mol 66.00745 ± 0.00085 474815-26-4*0 Hydroperoxyimidogen HOON (g, cis) 111.8 108.9 ± 2.8 kJ/mol 47.01348 ± 0.00061 877456-58-1*2 Chloromethylene CHCl (g) 320.26 320.55 ± 0.89 kJ/mol 48.4713 ± 0.0012 2108-20-5*0 Bromine atom Br (g, 2P1/2) 161.998 155.936 ± 0.056 kJ/mol 79.90400 ± 0.00100 10097-32-2*2 Methoxyethene CH2CHOCH3 (g) -89.0 -106.3 ± 1.1 kJ/mol 58.0791 ± 0.0025 107-25-5*0 Carbon atom C (g, quintuplet) 1114.959 1120.106 ± 0.047 kJ/mol 12.01070 ± 0.00080 7440-44-0*3 Water H2O (g, ortho) -238.648 -241.836 ± 0.026 kJ/mol 18.01528 ± 0.00033 7732-18-5*1 3-Imino-2-propen-1-ylidene CHCHCNH (g) 530.6 526.3 ± 1.2 kJ/mol 53.0627 ± 0.0024 916765-05-4*0 Cyanogen iodide cation [ICN]+ (g) 1271.5 1271.3 ± 1.6 kJ/mol 152.92136 ± 0.00080 34749-78-5*0 3-Imino-2-propen-1-ylidene CHCHCNH (g, triplet) 571.8 567.0 ± 1.6 kJ/mol 53.0627 ± 0.0024 916765-05-4*2 Fluoro(fluorooxy)methylene FCOF (g) -134.8 -136.0 ± 1.3 kJ/mol 66.00691 ± 0.00085 479587-30-9*0 Methoxyethene CH2CHOCH3 (g, trans) -81.7 -98.7 ± 2.4 kJ/mol 58.0791 ± 0.0025 107-25-5*1 Diazene HNNH (g, trans-cis-iso equilib) 207.09 199.96 ± 0.44 kJ/mol 30.02936 ± 0.00020 3618-05-1*0 Ethoxyethene CH2CHOCH2CH3 (g) -117.4 -135.9 ± 1.5 kJ/mol 72.1057 ± 0.0033 109-92-2*0 2-(Methylidyneamino)ethenyl CHCHNCH (g) 600.6 596.3 ± 1.2 kJ/mol 53.0627 ± 0.0024 123416-74-0*0 Nitrosyl nitrate ONONO2 (g) 48.3 40.4 ± 1.8 kJ/mol 92.0111 ± 0.0012 15969-55-8*0 2-(Methylidyneamino)ethenyl CHCHNCH (g, triplet) 634.4 630.4 ± 1.6 kJ/mol 53.0627 ± 0.0024 123416-74-0*2 Hydrazoic acid anion [HNNN]- (g) 309.0 303.1 ± 2.3 kJ/mol 43.02871 ± 0.00022 203264-98-6*0 Dichlorovinylidene CCCl2 (g) 421.6 424.8 ± 3.0 kJ/mol 94.9268 ± 0.0024 20394-25-6*0 Dioxohydrazine ONNO (g) 172.89 171.12 ± 0.14 kJ/mol 60.01228 ± 0.00062 16824-89-8*0 Water H2O (cr, l, eq.press.) -286.304 -285.832 ± 0.026 kJ/mol 18.01528 ± 0.00033 7732-18-5*499 Ethoxyethene CH2CHOCH2CH3 (g, cis-perp) -111.0 -134.8 ± 2.3 kJ/mol 72.1057 ± 0.0033 109-92-2*21 Ethoxyethene CH2CHOCH2CH3 (g, trans-trans) -110.4 -132.6 ± 2.7 kJ/mol 72.1057 ± 0.0033 109-92-2*1 Hydroxymethylene anion [HCOH]- (g) 147.1 144.2 ± 1.6 kJ/mol 30.02653 ± 0.00087 207914-87-2*0 Ethoxyethene CH2CHOCH2CH3 (g, trans-perp) -108.4 -131.6 ± 2.3 kJ/mol 72.1057 ± 0.0033 109-92-2*11 Hydrobromate ion [HBr]- (g) -5.9 -12.4 ± 4.3 kJ/mol 80.9125 ± 0.0010 85532-97-4*0 Diazene HNNH (g, trans-cis equilib) 207.09 199.96 ± 0.44 kJ/mol 30.02936 ± 0.00020 3618-05-1*1 Isocyanomethane CH3NC (cr,l) 145.9 ± 2.2 kJ/mol 41.0520 ± 0.0016 593-75-9*500 Peroxyformic acid HC(O)OOH (g) -279.27 -288.40 ± 0.90 kJ/mol 62.0248 ± 0.0012 107-32-4*0 Hydrogen peroxide H2O2 (aq) -190.76 ± 0.30 kJ/mol 34.01468 ± 0.00062 7722-84-1*800 2-Cyanovinyl CHCHCN (g) 447.8 445.4 ± 1.3 kJ/mol 52.0547 ± 0.0024 189141-20-6*0 2-Cyanovinylium [CHCHCN]+ (g, triplet) 1517.1 1515.1 ± 1.8 kJ/mol 52.0542 ± 0.0024 85398-67-0*2 2-Cyanovinyl anion [CHCHCN]- (g) 263.7 261.4 ± 1.8 kJ/mol 52.0553 ± 0.0024 *85398-67-0*0 Oxiranylidene CH2(CO) (g) 213.5 209.3 ± 1.4 kJ/mol 42.0367 ± 0.0016 50983-85-2*0 Chlorohydroxymethyl CH(Cl)OH (g) -54.9 -60.6 ± 1.1 kJ/mol 65.4787 ± 0.0012 147139-06-8*0 2-Isocyanovinyl CHCHNC (g) 543.1 541.7 ± 1.7 kJ/mol 52.0547 ± 0.0024 225798-14-1*0 O--HH Complex (H2)(O) (g, vdW C2v ?) 247.2 248.2 ± 2.0 kJ/mol 18.01528 ± 0.00033 *7732-18-5*102 Diazenide [NNH]- (g) 175.6 176.7 ± 1.6 kJ/mol 29.02197 ± 0.00016 71004-29-0*0 Cyanomethyliumyl [HCCN]+ (g) 1506.7 1508.2 ± 2.3 kJ/mol 39.0355 ± 0.0016 34447-38-6*0 Cyanomethylene anion [HCCN]- (g) 286.5 287.0 ± 1.5 kJ/mol 39.0366 ± 0.0016 12373-24-9*0 Cyanomethylene HCCN (g) 479.9 483.2 ± 1.1 kJ/mol 39.0361 ± 0.0016 2612-62-6*0 Trihydrogen cation [H3]+ (g, ortho) 1110.577 1106.695 ± 0.013 kJ/mol 3.02327 ± 0.00021 28132-48-1*1 Phosgene cation [CCl2O]+ (g) 897.1 896.0 ± 1.7 kJ/mol 98.9150 ± 0.0020 73249-38-4*0 Isocyanomethyliumyl [HCNC]+ (g) 1505.9 1507.8 ± 3.3 kJ/mol 39.0355 ± 0.0016 99045-54-2*0 Isocyanomethylene anion [HCNC]- (g) 400.5 401.2 ± 2.1 kJ/mol 39.0366 ± 0.0016 144141-01-5*0 Isocyanomethylene HCNC (g) 582.3 584.5 ± 1.7 kJ/mol 39.0361 ± 0.0016 78694-65-2*0 Chloroethane CH3CH2Cl (cr,l) -134.29 -135.92 ± 0.27 kJ/mol 64.5138 ± 0.0019 75-00-3*500 3-Oxo-1,2-propadien-1-ylium-1-yl [CCCO]+ (g) 1379.9 1385.2 ± 3.9 kJ/mol 52.0310 ± 0.0024 151455-13-9*0 3-Oxo-1,2-propadienylidene anion [CCCO]- (g) 223.9 229.7 ± 3.6 kJ/mol 52.0320 ± 0.0024 109292-50-4*0 Phosgene CCl2O (cr, l, I+liquid) -242.73 ± 0.27 kJ/mol 98.9155 ± 0.0020 75-44-5*501 Phosgene CCl2O (cr, l, II+liquid) -255.44 -242.73 ± 0.27 kJ/mol 98.9155 ± 0.0020 75-44-5*502 Nitrosodioxaziridine ONN(OO) (g, cis) 413.8 408.1 ± 3.2 kJ/mol 76.01168 ± 0.00091 132871-99-9*2 Chloro(chlorooxy)methylene ClCOCl (g) 73.5 73.9 ± 3.6 kJ/mol 98.9155 ± 0.0020 479587-31-0*0 Chloro(chlorooxy)methylene ClCOCl (g, trans) 98. 105. ± 15. kJ/mol 98.9155 ± 0.0020 479587-31-0*1 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 ± 0.033 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 ± 1.5 kJ/mol 20.17586 ± 0.00060 14175-50-9*0 Neon octacation [Ne]+8 (g) 92018.2 92018.2 ± 1.5 kJ/mol 20.17531 ± 0.00060 14782-26-4*0 Neon nonacation [Ne]+9 (g) 207396.1 207396.1 ± 1.5 kJ/mol 20.17476 ± 0.00060 15721-59-2*0 Neon cation Ne+ (g) 2080.662 2080.769 ± 0.000 kJ/mol 20.17915 ± 0.00060 14782-23-1*0 Neon decacation [Ne]+10 (g) 338828.3 338828.3 ± 1.5 kJ/mol 20.17421 ± 0.00060 32218-07-8*0 Argon dimer cation [Ar2]+ (g) 1393.760 1391.173 ± 0.018 kJ/mol 79.8955 ± 0.0020 17596-58-6*0 Argon cation Ar+ (g) 1520.571 1520.580 ± 0.000 kJ/mol 39.94745 ± 0.00100 14791-69-6*0 Argon dimer Ar2 (g) -1.013 -6.347 ± 0.0051 kJ/mol 79.8960 ± 0.0020 12595-59-4*0 Helium cation He+ (g) 2372.322 2372.322 ± 0.000 kJ/mol 4.0020534 ± 0.0000020 14234-48-1*0 Helium dication [He]+2 (g) 7622.839 7622.839 ± 0.000 kJ/mol 4.0015048 ± 0.0000020 12587-46-1*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 Argon anion Ar- (g, 2S1/2) 23. 23. ± 75. kJ/mol 39.94855 ± 0.00100 16544-90-4*1 Argon anion Ar- (g) 23. 23. ± 75. kJ/mol 39.94855 ± 0.00100 16544-90-4*0 Helium anion He- (g, 1s.2s2 2S1/2) 1868.43 1868.43 ± 0.11 kJ/mol 4.0031506 ± 0.0000020 14452-58-5*2 Helium anion He- (g, 1s.2s.2p 4P) 1904.823 1904.824 ± 0.0011 kJ/mol 4.0031506 ± 0.0000020 14452-58-5*3 Helium anion He- (g, 2p3 4S3/2) 5724.9 5724.9 ± 1.5 kJ/mol 4.0031506 ± 0.0000020 14452-58-5*4 Argon anion Ar- (g, 4S3/2) 1111.116 1111.116 ± 0.098 kJ/mol 39.94855 ± 0.00100 16544-90-4*2 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. 1.122p of the Thermochemical Network (2020); available at ATcT.anl.gov
4
P. B. Changala, T. L. Nguyen, J. H. Baraban, G. B. Ellison, J. F. Stanton, D. H. Bross, and B. Ruscic,
Active Thermochemical Tables: The Adiabatic Ionization Energy of Hydrogen Peroxide.
J. Phys. Chem. A 121 , 8799-8806 (2017)
[DOI: 10.1021/acs.jpca.7b06221] (highlighted on the journal cover )
5
D. Feller, D. H. Bross, and B. Ruscic,
Enthalpy of Formation of N2H4 (Hydrazine) Revisited.
J. Phys. Chem. A 121 , 6187-6198 (2017)
[DOI: 10.1021/acs.jpca.7b06017]
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]
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 ]).
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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