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

This version of ATcT results was generated from an expansion of version 1.122q [4, 5] to include a non-rigid rotor anharmonic oscillator (NRRAO) partition function for hydroxymethyl [6], as well as data on 42 additional species, some of which are related to soot formation mechanisms.

Species Name Formula Image    ΔfH°(0 K)    ΔfH°(298.15 K) Uncertainty Units Relative
Molecular
Mass		 ATcT ID
Methylium[CH3]+ (g)[CH3+]1099.3391095.396± 0.050kJ/mol15.03397 ±
0.00083		14531-53-4*0

Representative Geometry of [CH3]+ (g)

spin ON           spin OFF
          

Top contributors to the provenance of ΔfH° of [CH3]+ (g)

The 9 contributors listed below account for 63.8% of the provenance of ΔfH° of [CH3]+ (g).

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
49.21936.1 2 H2 (g) + C (graphite) → CH4 (g) ΔrG°(1165 K) = 37.521 ± 0.068 kJ/molSmith 1946, note COf, 3rd Law
4.51958.1 CH4 (g) → [CH3]+ (g) + H (g) ΔrH°(0 K) = 14.32271 ± 0.00013 eVChang 2017
3.2120.2 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
2.21935.4 CH4 (g) + 2 O2 (g) → CO2 (g) + 2 H2O (cr,l) ΔrH°(298.15 K) = -890.61 ± 0.21 kJ/molDale 2002
1.41935.6 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
0.81935.5 CH4 (g) + 2 O2 (g) → CO2 (g) + 2 H2O (cr,l) ΔrH°(298.15 K) = -890.43 ± 0.35 kJ/molAlexandrov 2002a, Alexandrov 2002
0.81935.1 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
0.71843.2 CO (g) → C+ (g) + O (g) ΔrH°(0 K) = 22.3713 ± 0.0015 eVNg 2007
0.61948.13 CH3 (g) → C (g) + 3 H (g) ΔrH°(0 K) = 289.11 ± 0.10 kcal/molFeller 2016, note unc2

Top 10 species with enthalpies of formation correlated to the ΔfH° of [CH3]+ (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
96.9 MethaneCH4 (g)C-66.557-74.526± 0.049kJ/mol16.04246 ±
0.00085		74-82-8*0
90.5 MethylCH3 (g)[CH3]149.866146.452± 0.055kJ/mol15.03452 ±
0.00083		2229-07-4*0
78.5 Methane cation[CH4]+ (g)[CH4+]1150.6731144.290± 0.062kJ/mol16.04191 ±
0.00085		20741-88-2*0
32.7 EthaneCH3CH3 (g)CC-68.41-84.04± 0.13kJ/mol30.0690 ±
0.0017		74-84-0*0
32.6 Carbon cationC+ (g)[C+]1797.8511803.449± 0.045kJ/mol12.01015 ±
0.00080		14067-05-1*0
32.6 CarbonC (g, quintuplet)[C]1114.9611120.107± 0.045kJ/mol12.01070 ±
0.00080		7440-44-0*3
32.6 CarbonC (g, singlet)[C]833.329838.475± 0.045kJ/mol12.01070 ±
0.00080		7440-44-0*2
32.6 CarbonC (g, triplet)[C]711.398716.883± 0.045kJ/mol12.01070 ±
0.00080		7440-44-0*1
32.6 CarbonC (g)[C]711.398716.883± 0.045kJ/mol12.01070 ±
0.00080		7440-44-0*0
32.5 Carbon anionC- (g)[C-]589.621594.768± 0.046kJ/mol12.01125 ±
0.00080		14337-00-9*0

Most Influential reactions involving [CH3]+ (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
0.9591958.1 CH4 (g) → [CH3]+ (g) + H (g) ΔrH°(0 K) = 14.32271 ± 0.00013 eVChang 2017
0.5004693.2 CH3I (g) → [CH3]+ (g) + I (g) ΔrH°(0 K) = 12.251 ± 0.0024 eVLee 2007
0.4131951.1 CH3 (g) → [CH3]+ (g) ΔrH°(0 K) = 79370.4 ± 3 cm-1Schulenburg 2006, note CH3
0.4131951.2 CH3 (g) → [CH3]+ (g) ΔrH°(0 K) = 79369.9 ± 3 cm-1Schulenburg 2006, note CH3
0.2814693.1 CH3I (g) → [CH3]+ (g) + I (g) ΔrH°(0 K) = 12.248 ± 0.003 (×1.067) eVBodi 2009
0.0894671.1 CH3Br (g) → [CH3]+ (g) + Br (g) ΔrH°(0 K) = 12.834 ± 0.002 (×4.362) eVSong 2001
0.0791951.4 CH3 (g) → [CH3]+ (g) ΔrH°(0 K) = 79363 ± 3 (×2.278) cm-1Blush 1993, note CH3
0.0454693.3 CH3I (g) → [CH3]+ (g) + I (g) ΔrH°(0 K) = 12.243 ± 0.008 eVLee 2007, Bodi 2009
0.0361952.12 CH3 (g) → [CH3]+ (g) ΔrH°(0 K) = 226.946 ± 0.029 kcal/molFeller 2017a
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. 1.122r of the Thermochemical Network, Argonne National Laboratory, Lemont, Illinois 2021 [DOI: 10.17038/CSE/1822363]; available at ATcT.anl.gov
4   D. Feller, D. H. Bross, and B. Ruscic,
Enthalpy of Formation of C2H2O4 (Oxalic Acid) from High-Level Calculations and the Active Thermochemical Tables Approach.
J. Phys. Chem. A 123, 3481-3496 (2019) [DOI: 10.1021/acs.jpca.8b12329]
5   B. K. Welch, R. Dawes, D. H. Bross, and B. Ruscic,
An Automated Thermochemistry Protocol Based on Explicitly Correlated Coupled-Cluster Theory: The Methyl and Ethyl Peroxy Families.
J. Phys. Chem. A 123, 5673-5682 (2019) [DOI: 10.1021/acs.jpca.8b12329]
6   D. H. Bross, H.-G. Yu, L. B. Harding, and B. Ruscic,
Active Thermochemical Tables: The Partition Function of Hydroxymethyl (CH2OH) Revisited.
J. Phys. Chem. A 123, 4212-4231 (2019) [DOI: 10.1021/acs.jpca.9b02295]
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.