Selected ATcT [1, 2] enthalpy of formation based on version 1.156 of the Thermochemical Network [3]

This version of ATcT results[3] was generated by additional expansion of version 1.148 to include species relevant to a recent study of the oxidation of ethylene [4] as well as new measurements that led to refining the thermochemistry of CF and SiF and their cations [5].

Methylidyne

Formula: CH (g)
CAS RN: 3315-37-5
ATcT ID: 3315-37-5*0
SMILES: [CH]
InChI: InChI=1S/CH/h1H
InChIKey: VRLIPUYDFBXWCH-UHFFFAOYSA-N
Hills Formula: C1H1

2D Image:

[CH]
Aliases: CH; Methylidyne; Methylidyne radical; Methyne radical; Methyne; Carbyne; Hydridocarbon; Carbon hydride; Carbon monohydride
Relative Molecular Mass: 13.01864 ± 0.00080

   ΔfH°(0 K)   ΔfH°(298.15 K)UncertaintyUnits
592.990596.324± 0.081kJ/mol

3D Image of CH (g)

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

The 20 contributors listed below account only for 59.5% of the provenance of ΔfH° of CH (g).
A total of 302 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
11.82422.1 CH (g) → C (g) H (g) ΔrH°(0 K) = 27954.0 ± 15 cm-1Thorpe 2021a, Thorpe 2021
11.82422.2 CH (g) → C (g) H (g) ΔrH°(0 K) = 27955.6 ± 15 cm-1Thorpe 2021a
11.72425.1 CH (g) → [CH]+ (g) ΔrH°(0 K) = 85828.7 ± 15 cm-1Thorpe 2021a, Thorpe 2021
3.32423.12 CH (g) → C (g) H (g) ΔrH°(0 K) = 80.01 ± 0.08 kcal/molFeller 2014, note unc
3.22423.2 CH (g) → C (g) H (g) ΔrH°(0 K) = 334.55 ± 0.34 kJ/molCsaszar 2002
2.12423.11 CH (g) → C (g) H (g) ΔrH°(0 K) = 79.94 ± 0.1 kcal/molFeller 2008
1.92437.8 CH2 (g, triplet) → CH (g) H (g) ΔrH°(0 K) = 418.04 ± 0.35 kJ/molCsaszar 2003
1.72359.1 H2 (g) C (graphite) → CH4 (g) ΔrG°(1165 K) = 37.521 ± 0.068 kJ/molSmith 1946, note COf, 3rd Law
1.62252.11 CO (g) → C (g) O (g) ΔrH°(0 K) = 1071.92 ± 0.10 (×1.242) kJ/molThorpe 2021
1.22262.2 CO (g) → C+ (g) O (g) ΔrH°(0 K) = 22.3713 ± 0.0015 eVNg 2007
1.22422.6 CH (g) → C (g) H (g) ΔrH°(0 K) = 334.49 ± 0.56 kJ/molHarding 2008
0.92421.12 CH (g) → C (g) H (g) ΔrH°(0 K) = 79.95 ± 0.15 kcal/molKarton 2007a
0.92438.5 CH2 (g, singlet) → CH (g) H (g) ΔrH°(0 K) = 90.97 ± 0.12 kcal/molFeller 2014
0.92426.13 [CH]- (g) → CH (g) ΔrH°(0 K) = 1.215 ± 0.005 eVFeller 2016, Feller 2016a, note unc3
0.86451.11 CF (g) → C (g) F (g) ΔrH°(0 K) = 545.41 ± 0.56 kJ/molHarding 2008
0.8125.2 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
0.72422.4 CH (g) → C (g) H (g) ΔrH°(0 K) = 334.47 ± 0.70 kJ/molHarding 2008
0.72437.4 CH2 (g, triplet) → CH (g) H (g) ΔrH°(0 K) = 417.96 ± 0.56 kJ/molHarding 2008
0.62422.5 CH (g) → C (g) H (g) ΔrH°(0 K) = 334.48 ± 0.74 kJ/molHarding 2008
0.62422.3 CH (g) → C (g) H (g) ΔrH°(0 K) = 334.68 ± 0.75 kJ/molTajti 2004, est unc

Top 10 species with enthalpies of formation correlated to the ΔfH° of CH (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
100.0 MethylidyneCH (g, doublet)[CH]592.990596.324± 0.081kJ/mol13.01864 ±
0.00080
3315-37-5*1
67.0 FluoromethylidyneCF (g)[C]F243.19246.79± 0.11kJ/mol31.00910 ±
0.00080
3889-75-6*0
48.0 CarbonC (g, quintuplet)[C]1114.9631120.109± 0.040kJ/mol12.01070 ±
0.00080
7440-44-0*3
48.0 CarbonC (g, singlet)[C]833.331838.477± 0.040kJ/mol12.01070 ±
0.00080
7440-44-0*2
48.0 Carbon cationC+ (g)[C+]1797.8531803.451± 0.040kJ/mol12.01015 ±
0.00080
14067-05-1*0
48.0 CarbonC (g, triplet)[C]711.400716.885± 0.040kJ/mol12.01070 ±
0.00080
7440-44-0*1
48.0 CarbonC (g)[C]711.400716.885± 0.040kJ/mol12.01070 ±
0.00080
7440-44-0*0
47.9 Carbon dication[C]+2 (g)[C++]4150.4694155.616± 0.040kJ/mol12.00960 ±
0.00080
16092-61-8*0
47.8 Carbon anionC- (g)[C-]589.624594.770± 0.040kJ/mol12.01125 ±
0.00080
14337-00-9*0
47.5 Methyliumylidene[CH]+ (g)[CH+]1619.7571623.100± 0.041kJ/mol13.01809 ±
0.00080
24361-82-8*0

Most Influential reactions involving CH (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
1.0002430.1 CH (g) → CH (g, doublet) ΔrH°(0 K) = 0 ± 0 cm-1Botterud 1973, Huber 1979
0.2384331.11 HCCO (g) → CH (g) CO (g) ΔrH°(0 K) = 302.2 ± 1.1 kJ/molSzalay 2004
0.1948386.5 SiF (g, doublet) CH (g) → SiH (g) CF (g) ΔrH°(0 K) = 19.61 ± 0.25 kcal/molKarton 2007b
0.1942426.13 [CH]- (g) → CH (g) ΔrH°(0 K) = 1.215 ± 0.005 eVFeller 2016, Feller 2016a, note unc3
0.1605595.10 NCN (g) H (g) → CH (g) N2 (g) ΔrH°(0 K) = -74.42 ± 1.0 kJ/molHarding 2018
0.1572425.1 CH (g) → [CH]+ (g) ΔrH°(0 K) = 85828.7 ± 15 cm-1Thorpe 2021a, Thorpe 2021
0.1562422.1 CH (g) → C (g) H (g) ΔrH°(0 K) = 27954.0 ± 15 cm-1Thorpe 2021a, Thorpe 2021
0.1562422.2 CH (g) → C (g) H (g) ΔrH°(0 K) = 27955.6 ± 15 cm-1Thorpe 2021a
0.1486457.6 CF (g) CH4 (g) → 4 CH (g) CF4 (g) ΔrH°(0 K) = 128.62 ± 0.20 kcal/molKarton 2007b
0.1486457.5 CF (g) CH4 (g) → 4 CH (g) CF4 (g) ΔrH°(0 K) = 128.63 ± 0.20 kcal/molKarton 2007b
0.1486457.4 CF (g) CH4 (g) → 4 CH (g) CF4 (g) ΔrH°(0 K) = 128.62 ± 0.20 kcal/molKarton 2007b
0.0985625.9 HNCN (g, doublet) → CH (g) N2 (g) ΔrH°(0 K) = 271.15 ± 2.0 kJ/molKlippenstein 2017
0.0822437.8 CH2 (g, triplet) → CH (g) H (g) ΔrH°(0 K) = 418.04 ± 0.35 kJ/molCsaszar 2003
0.0826458.10 CF (g) H2 (g) → 2 CH (g) F2 (g) ΔrH°(0 K) = 699.43 ± 0.56 kJ/molHarding 2008
0.0726458.7 CF (g) H2 (g) → 2 CH (g) F2 (g) ΔrH°(0 K) = 699.65 ± 0.60 kJ/molTajti 2004, est unc
0.0666457.3 CF (g) CH4 (g) → 4 CH (g) CF4 (g) ΔrH°(0 K) = 128.58 ± 0.30 kcal/molKarton 2007b
0.0526458.8 CF (g) H2 (g) → 2 CH (g) F2 (g) ΔrH°(0 K) = 699.79 ± 0.70 kJ/molHarding 2008
0.0515695.6 HNNC (g, doublet) → CH (g) N2 (g) ΔrH°(0 K) = 23.68 ± 1.2 kcal/molHarding 2008a, est unc
0.0476458.9 CF (g) H2 (g) → 2 CH (g) F2 (g) ΔrH°(0 K) = 699.72 ± 0.74 kJ/molHarding 2008
0.0475625.1 HNCN (g, doublet) → CH (g) N2 (g) ΔrH°(0 K) = 2.80 ± 0.03 eVBise 2001


References
1   B. Ruscic, R. E. Pinzon, M. L. Morton, G. von Laszewski, S. Bittner, S. G. Nijsure, K. A. Amin, M. Minkoff, and A. F. Wagner,
Introduction to Active Thermochemical Tables: Several "Key" Enthalpies of Formation Revisited.
J. Phys. Chem. A 108, 9979-9997 (2004) [DOI: 10.1021/jp047912y]
2   B. Ruscic, R. E. Pinzon, G. von Laszewski, D. Kodeboyina, A. Burcat, D. Leahy, D. Montoya, and A. F. Wagner,
Active Thermochemical Tables: Thermochemistry for the 21st Century.
J. Phys. Conf. Ser. 16, 561-570 (2005) [DOI: 10.1088/1742-6596/16/1/078]
3   B. Ruscic and D. H. Bross,
Active Thermochemical Tables (ATcT) values based on ver. 1.156 of the Thermochemical Network (2024); available at ATcT.anl.gov
4   N. A. Seifert, B. Ruscic, R. Sivaramakrishnan, and K. Prozument,
The C2H4O Isomers in the Oxidation of Ethylene
J. Mol. Spectrosc. 398, 111847/1-8 (2023) [DOI: 10.1016/j.jms.2023.111847]
5   U. Jacovella, B. Ruscic, N. L. Chen, H.-L. Le, S. Boyé-Péronne, S. Hartweg, M. Roy-Chowdhury, G. A. Garcia, J.-C. Loison, and B. Gans,
Refining Thermochemical Properties of CF, SiF, and Their Cations by Combining Photoelectron Spectroscopy, Quantum Chemical Calculations, and the Active Thermochemical Tables Approach
Phys. Chem. Chem. Phys. 25, 30838-30847 (2023) [DOI: 10.1039/D3CP04244H]
6   B. Ruscic,
Uncertainty Quantification in Thermochemistry, Benchmarking Electronic Structure Computations, and Active Thermochemical Tables.
Int. J. Quantum Chem. 114, 1097-1101 (2014) [DOI: 10.1002/qua.24605]
7   B. Ruscic and D. H. Bross,
Thermochemistry
Computer Aided Chem. Eng. 45, 3-114 (2019) [DOI: 10.1016/B978-0-444-64087-1.00001-2]

Formula
The aggregate state is given in parentheses following the formula, such as: g - gas-phase, cr - crystal, l - liquid, etc.

Uncertainties
The listed uncertainties correspond to estimated 95% confidence limits, as customary in thermochemistry (see, for example, Ruscic [6] and Ruscic and Bross[7]).
Note that an uncertainty of ± 0.000 kJ/mol indicates that the estimated uncertainty is < ± 0.0005 kJ/mol.

Website Functionality Credits
The reorganization of the website was developed and implemented by David H. Bross (ANL).
The find function is based on the complete Species Dictionary entries for the appropriate version of the ATcT TN.
The molecule images are rendered by Indigo-depict.
The XYZ renderings are based on Jmol: an open-source Java viewer for chemical structures in 3D. http://www.jmol.org/.

Acknowledgement
This work was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences and Biosciences under Contract No. DE-AC02-06CH11357.