Selected ATcT [1, 2] enthalpy of formation based on version 1.122d of the Thermochemical Network [3]

This version of ATcT results was generated from an expansion of version 1.122b [4][5] to include the enthalpies of formation of methylamine, dimethylamine and trimethylamine that were used as reference values to derive the bond dissociation energies of 20 diatomic molecules containing 3d transition metals.[6].

Species Name Formula Image    ΔfH°(0 K)    ΔfH°(298.15 K) Uncertainty Units Relative
Molecular
Mass		 ATcT ID
MethaneCH4 (g)C-66.556-74.525± 0.056kJ/mol16.04246 ±
0.00085		74-82-8*0

Representative Geometry of CH4 (g)

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Top contributors to the provenance of ΔfH° of CH4 (g)

The 20 contributors listed below account only for 83.4% of the provenance of ΔfH° of CH4 (g).
A total of 67 contributors would be needed to account for 90% of the provenance.

Please note: The list is limited to 20 most important contributors or, if less, a number sufficient to account for 90% of the provenance. The Reference acts as a further link to the relevant references and notes for the measurement. The Measured Quantity is normaly given in the original units; in cases where we have reinterpreted the original measurement, the listed value may differ from that given by the authors. The quoted uncertainty is the a priori uncertainty used as input when constructing the initial Thermochemical Network, and corresponds either to the value proposed by the original authors or to our estimate; if an additional multiplier is given in parentheses immediately after the prior uncertainty, it corresponds to the factor by which the prior uncertainty needed to be multiplied during the ATcT analysis in order to make that particular measurement consistent with the prevailing knowledge contained in the Thermochemical Network.

Contribution
(%)		TN
ID		 Reaction Measured Quantity Reference
66.21852.1 2 H2 (g) + C (graphite) → CH4 (g) ΔrG°(1165 K) = 37.521 ± 0.068 kJ/molSmith 1946, note COf, 3rd Law
4.01851.4 CH4 (g) + 2 O2 (g) → CO2 (g) + 2 H2O (cr,l) ΔrH°(298.15 K) = -890.61 ± 0.21 kJ/molDale 2002
2.61851.6 CH4 (g) + 2 O2 (g) → CO2 (g) + 2 H2O (cr,l) ΔrH°(298.15 K) = -890.44 ± 0.26 kJ/molGOMB Ref Calorimeter, Alexandrov 2002
2.2118.2 1/2 O2 (g) + H2 (g) → H2O (cr,l) ΔrH°(298.15 K) = -285.8261 ± 0.040 kJ/molRossini 1939, Rossini 1931, Rossini 1931b, note H2Oa, Rossini 1930
1.41851.1 CH4 (g) + 2 O2 (g) → CO2 (g) + 2 H2O (cr,l) ΔrH°(303.15 K) = -889.849 ± 0.350 kJ/molRossini 1931a, Rossini 1931b, Prosen 1945, Rossini 1940, note CH4
1.41851.5 CH4 (g) + 2 O2 (g) → CO2 (g) + 2 H2O (cr,l) ΔrH°(298.15 K) = -890.43 ± 0.35 kJ/molAlexandrov 2002a, Alexandrov 2002
0.91851.2 CH4 (g) + 2 O2 (g) → CO2 (g) + 2 H2O (cr,l) ΔrH°(298.15 K) = -890.699 ± 0.430 kJ/molPittam 1972, note CH4a
0.51872.7 CH4 (g) → [CH3]+ (g) + H (g) ΔrH°(0 K) = 14.321 ± 0.001 eVBodi 2009a
0.51846.12 CH4 (g) → C (g) + 4 H (g) ΔrH°(0 K) = 392.46 ± 0.15 kcal/molKarton 2007a
0.41866.4 CH3 (g) → C (g) + 3 H (g) ΔrH°(0 K) = 1209.50 ± 0.56 kJ/molHarding 2008
0.31775.2 CO (g) → C+ (g) + O (g) ΔrH°(0 K) = 22.3713 ± 0.0015 eVNg 2007
0.31865.11 CH3 (g) → C (g) + 3 H (g) ΔrH°(0 K) = 289.08 ± 0.15 kcal/molKarton 2008
0.21845.6 CH4 (g) → C (g) + 4 H (g) ΔrH°(0 K) = 392.45 ± 0.2 kcal/molFeller 2008
0.21846.11 CH4 (g) → C (g) + 4 H (g) ΔrH°(0 K) = 392.47 ± 0.20 kcal/molKarton 2007
0.23912.1 CH3Cl (g) + 3/2 O2 (g) → CO2 (g) + H2O (cr,l) + HCl (aq, 600 H2O) ΔrH°(298.15 K) = -764.00 ± 0.50 (×1.067) kJ/molFletcher 1971
0.21872.2 CH4 (g) → [CH3]+ (g) + H (g) ΔrH°(0 K) = 14.323 ± 0.001 (×1.414) eVWeitzel 1999, Weitzel 2001
0.21866.2 CH3 (g) → C (g) + 3 H (g) ΔrH°(0 K) = 1209.48 ± 0.70 kJ/molHarding 2008
0.22335.1 CH3OH (g) → CH4 (g) + O (g, singlet) ΔrH°(0 K) = 133.94 ± 0.17 kcal/molNguyen 2015
0.23674.2 C (graphite) + 2 F2 (g) → CF4 (g) ΔrH°(298.15 K) = -223.024 ± 0.157 kcal/molGreenberg 1968
0.21866.3 CH3 (g) → C (g) + 3 H (g) ΔrH°(0 K) = 1209.48 ± 0.74 kJ/molHarding 2008

Top 10 species with enthalpies of formation correlated to the ΔfH° of CH4 (g)

Please note: The correlation coefficients are obtained by renormalizing the off-diagonal elements of the covariance matrix by the corresponding variances.
The correlation coefficient is a number from -1 to 1, with 1 representing perfectly correlated species, -1 representing perfectly anti-correlated species, and 0 representing perfectly uncorrelated species.

Correlation
Coefficent
(%)		Species Name Formula Image    ΔfH°(0 K)    ΔfH°(298.15 K) Uncertainty Units Relative
Molecular
Mass		 ATcT ID
62.4 Methylium[CH3]+ (g)[CH3+]1099.2341095.291± 0.078kJ/mol15.03397 ±
0.00083		14531-53-4*0
58.8 MethylCH3 (g)[CH3]149.829146.414± 0.080kJ/mol15.03452 ±
0.00083		2229-07-4*0
27.5 Methyl iodideCH3I (g)CI24.4014.86± 0.18kJ/mol141.93899 ±
0.00083		74-88-4*0
27.5 Methyl iodide cation[CH3I]+ (g)C[I+]944.69935.29± 0.18kJ/mol141.93844 ±
0.00083		12538-72-6*0
24.9 Methyl iodideCH3I (l)CI-12.28± 0.20kJ/mol141.93899 ±
0.00083		74-88-4*590
22.9 WaterH2O (l, eq.press.)O-285.838± 0.027kJ/mol18.01528 ±
0.00033		7732-18-5*589
22.9 Oxonium[H3O]+ (aq)[OH3+]-285.836± 0.027kJ/mol19.02267 ±
0.00037		13968-08-6*800
22.9 WaterH2O (l)O-285.836± 0.027kJ/mol18.01528 ±
0.00033		7732-18-5*590
22.9 WaterH2O (cr,l)O-286.308-285.836± 0.027kJ/mol18.01528 ±
0.00033		7732-18-5*500
22.9 WaterH2O (cr, l, eq.press.)O-286.310-285.838± 0.027kJ/mol18.01528 ±
0.00033		7732-18-5*499

Most Influential reactions involving CH4 (g)

Please note: The list, which is based on a hat (projection) matrix analysis, is limited to no more than 20 largest influences.

Influence
Coefficient		 TN
ID		 Reaction Measured Quantity Reference
0.7261849.3 [CH4]- (g) → CH4 (g) ΔrH°(0 K) = -0.997 ± 0.061 eVRuscic G4
0.6621852.1 2 H2 (g) + C (graphite) → CH4 (g) ΔrG°(1165 K) = 37.521 ± 0.068 kJ/molSmith 1946, note COf, 3rd Law
0.4581847.1 CH4 (g) → [CH4]+ (g) ΔrH°(0 K) = 101752.2 ± 30 cm-1Worner 2007, note unc
0.3951872.7 CH4 (g) → [CH3]+ (g) + H (g) ΔrH°(0 K) = 14.321 ± 0.001 eVBodi 2009a
0.3024267.9 CH2CHF (g) + CH4 (g) → CH2CH2 (g) + CH3F (g) ΔrH°(0 K) = 8.36 ± 0.20 kcal/molKarton 2011
0.2604300.10 HCCF (g) + CH3F (g) → FCCF (g) + CH4 (g) ΔrH°(0 K) = 14.03 ± 0.20 kcal/molKarton 2011
0.2531847.10 CH4 (g) → [CH4]+ (g) ΔrH°(0 K) = 12.616 ± 0.005 eVRabalais 1971, est unc
0.2531859.5 [CH5]+ (g) + CO2 (g) → [HOCO]+ (g) + CH4 (g) ΔrG°(296 K) = 7.92 ± 0.20 kJ/molBohme 1973a, 3rd Law, note unc
0.2291859.7 [CH5]+ (g) + CO2 (g) → [HOCO]+ (g) + CH4 (g) ΔrG°(296 K) = 7.82 ± 0.21 kJ/molHemsworth 1973, 3rd Law, note unc
0.2284299.10 HCCH (g) + CH3F (g) → HCCF (g) + CH4 (g) ΔrH°(0 K) = 8.81 ± 0.20 kcal/molKarton 2011
0.2212122.8 CH2NH2 (g) + CH4 (g) → CH3NH2 (g) + CH3 (g) ΔrH°(0 K) = 12.19 ± 0.20 kcal/molKarton 2011
0.2174304.2 HCCBr (g) + CH3Br (g) → BrCCBr (g) + CH4 (g) ΔrH°(0 K) = 0.98 ± 1.2 kcal/molRuscic G3
0.2174304.1 HCCBr (g) + CH3Br (g) → BrCCBr (g) + CH4 (g) ΔrH°(0 K) = 1.31 ± 1.2 kcal/molRuscic G3B3
0.2103903.7 4 CH3F (g) → CF4 (g) + 3 CH4 (g) ΔrH°(0 K) = -218.8 ± 2.0 kJ/molKlopper 2010a, est unc
0.2091859.6 [CH5]+ (g) + CO2 (g) → [HOCO]+ (g) + CH4 (g) ΔrG°(296 K) = 7.72 ± 0.22 kJ/molBohme 1973a, 3rd Law, note unc
0.2054232.11 CH3CH2F (g) + CH4 (g) → CH3F (g) + CH3CH3 (g) ΔrH°(0 K) = 6.78 ± 0.20 kcal/molKarton 2011
0.1971872.2 CH4 (g) → [CH3]+ (g) + H (g) ΔrH°(0 K) = 14.323 ± 0.001 (×1.414) eVWeitzel 1999, Weitzel 2001
0.1854303.1 HCCH (g) + CH3Br (g) → HCCBr (g) + CH4 (g) ΔrH°(0 K) = 2.09 ± 1.2 kcal/molRuscic G3B3
0.1854303.2 HCCH (g) + CH3Br (g) → HCCBr (g) + CH4 (g) ΔrH°(0 K) = 1.68 ± 1.2 kcal/molRuscic G3
0.1821849.4 [CH4]- (g) → CH4 (g) ΔrH°(0 K) = -0.852 ± 0.092 (×1.325) eVRuscic CBS-n
References (for your convenience, also available in RIS and BibTex format)
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. 1.122d of the Thermochemical Network, Argonne National Laboratory (2018); available at ATcT.anl.gov
4   B. Ruscic,
Active Thermochemical Tables: Sequential Bond Dissociation Enthalpies of Methane, Ethane, and Methanol and the Related Thermochemistry.
J. Phys. Chem. A 119, 7810-7837 (2015) [DOI: 10.1021/acs.jpca.5b01346]
5   T. L. Nguyen, J. H. Baraban, B. Ruscic, and J. F. Stanton,
On the HCN – HNC Energy Difference.
J. Phys. Chem. A 119, 10929-10934 (2015) [DOI: 10.1021/acs.jpca.5b08406]
6   L. Cheng, J. Gauss, B. Ruscic, P. Armentrout, and J. Stanton,
Bond Dissociation Energies for Diatomic Molecules Containing 3d Transition Metals: Benchmark Scalar-Relativistic Coupled-Cluster Calculations for Twenty Molecules.
J. Chem. Theory Comput. 13, 1044-1056 (2017) [DOI: 10.1021/acs.jctc.6b00970]
7   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 [7]).
Note that an uncertainty of ± 0.000 kJ/mol indicates that the estimated uncertainty is < ± 0.0005 kJ/mol.
Website Functionality Credits
The reorganization of the website was developed and implemented by David H. Bross (ANL).
The find function is based on the complete Species Dictionary entries for the appropriate version of the ATcT TN.
The molecule images are rendered by Indigo-depict.
The XYZ renderings are based on Jmol: an open-source Java viewer for chemical structures in 3D. http://www.jmol.org/.
Acknowledgement
This work was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences and Biosciences under Contract No. DE-AC02-06CH11357.