Selected ATcT [1, 2] enthalpy of formation based on version 1.130 of the Thermochemical Network [3]

This version of ATcT results[4] was generated by additional expansion of version 1.128 [5,6] to include with the calculations provided in reference [4].

Methylidyne

Formula: CH (g, doublet)

CAS RN: 3315-37-5

ATcT ID: 3315-37-5*1

SMILES: [CH]

InChI: InChI=1S/CH/h1H

InChIKey: VRLIPUYDFBXWCH-UHFFFAOYSA-N

Hills Formula: C1H1

2D Image:

Aliases: CH; Methylidyne; Methylidyne radical; Methyne radical; Methyne; Carbyne; Hydridocarbon; Carbon hydride; Carbon monohydride

Relative Molecular Mass: 13.01864 ± 0.00080

Δ_fH°(0 K)	Δ_fH°(298.15 K)	Uncertainty	Units
592.832	596.166	± 0.095	kJ/mol

3D Image of CH (g, doublet)

spin ON spin OFF

Top contributors to the provenance of Δ_fH° of CH (g, doublet)

The 20 contributors listed below account only for 54.7% of the provenance of Δ_fH° of CH (g, doublet).
A total of 227 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
22.0	2343.12	CH (g) → C (g) + H (g)	Δ_rH°(0 K) = 80.01 ± 0.04 kcal/mol	Feller 2014
5.3	2343.2	CH (g) → C (g) + H (g)	Δ_rH°(0 K) = 334.74 ± 0.34 kJ/mol	Csaszar 2002
3.5	2343.11	CH (g) → C (g) + H (g)	Δ_rH°(0 K) = 79.99 ± 0.1 kcal/mol	Feller 2008
2.9	2357.8	CH2 (g, triplet) → CH (g) + H (g)	Δ_rH°(0 K) = 417.85 ± 0.35 kJ/mol	Csaszar 2003
1.9	2342.4	CH (g) → C (g) + H (g)	Δ_rH°(0 K) = 334.41 ± 0.56 kJ/mol	Harding 2008
1.7	2357.12	CH2 (g, triplet) → CH (g) + H (g)	Δ_rH°(0 K) = 99.75 ± 0.08 (×1.384) kcal/mol	Feller 2014
1.5	2341.12	CH (g) → C (g) + H (g)	Δ_rH°(0 K) = 80.00 ± 0.15 kcal/mol	Karton 2007a
1.5	2346.13	[CH]- (g) → CH (g)	Δ_rH°(0 K) = 1.215 ± 0.005 eV	Feller 2016, note unc3
1.4	2358.5	CH2 (g, singlet) → CH (g) + H (g)	Δ_rH°(0 K) = 90.97 ± 0.12 kcal/mol	Feller 2014
1.4	6198.11	CF (g) → C (g) + F (g)	Δ_rH°(0 K) = 545.41 ± 0.56 kJ/mol	Harding 2008
1.3	2279.1	2 H2 (g) + C (graphite) → CH4 (g)	Δ_rG°(1165 K) = 37.521 ± 0.068 kJ/mol	Smith 1946, note COf, 3rd Law
1.3	2172.11	CO (g) → C (g) + O (g)	Δ_rH°(0 K) = 1071.92 ± 0.10 (×1.215) kJ/mol	Thorpe 2021
1.2	2342.2	CH (g) → C (g) + H (g)	Δ_rH°(0 K) = 334.39 ± 0.70 kJ/mol	Harding 2008
1.1	2357.4	CH2 (g, triplet) → CH (g) + H (g)	Δ_rH°(0 K) = 418.04 ± 0.56 kJ/mol	Harding 2008
1.1	2342.3	CH (g) → C (g) + H (g)	Δ_rH°(0 K) = 334.40 ± 0.74 kJ/mol	Harding 2008
1.0	2342.1	CH (g) → C (g) + H (g)	Δ_rH°(0 K) = 334.70 ± 0.75 kJ/mol	Tajti 2004, est unc
1.0	2345.2	CH (g) → [CH]+ (g)	Δ_rH°(0 K) = 10.640 ± 0.008 eV	Gans 2016, as quoted by CODATA Key Vals
0.9	2356.4	CH2 (g, triplet) → CH (g) + H (g)	Δ_rH°(0 K) = 99.87 ± 0.15 kcal/mol	Karton 2008
0.9	6198.9	CF (g) → C (g) + F (g)	Δ_rH°(0 K) = 545.72 ± 0.70 kJ/mol	Harding 2008
0.9	2182.2	CO (g) → C+ (g) + O (g)	Δ_rH°(0 K) = 22.3713 ± 0.0015 eV	Ng 2007

Top 10 species with enthalpies of formation correlated to the Δ_fH° of CH (g, doublet)

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	Δ_fH°(0 K)	Δ_fH°(298.15 K)	Uncertainty	Units	Relative Molecular Mass	ATcT ID
100.0	Methylidyne	CH (g)	592.832	596.166	± 0.095	kJ/mol	13.01864 ± 0.00080	3315-37-5*0
72.3	Fluoromethylidyne	CF (g)	243.11	246.71	± 0.12	kJ/mol	31.00910 ± 0.00080	3889-75-6*0
40.8	Carbon	C (g)	711.396	716.881	± 0.041	kJ/mol	12.01070 ± 0.00080	7440-44-0*0
40.8	Carbon	C (g, triplet)	711.396	716.881	± 0.041	kJ/mol	12.01070 ± 0.00080	7440-44-0*1
40.8	Carbon cation	C+ (g)	1797.849	1803.447	± 0.041	kJ/mol	12.01015 ± 0.00080	14067-05-1*0
40.8	Carbon	C (g, quintuplet)	1114.959	1120.105	± 0.041	kJ/mol	12.01070 ± 0.00080	7440-44-0*3
40.8	Carbon	C (g, singlet)	833.327	838.474	± 0.041	kJ/mol	12.01070 ± 0.00080	7440-44-0*2
40.7	Carbon dication	[C]+2 (g)	4150.466	4155.612	± 0.041	kJ/mol	12.00960 ± 0.00080	16092-61-8*0
40.6	Carbon anion	C- (g)	589.620	594.766	± 0.041	kJ/mol	12.01125 ± 0.00080	14337-00-9*0
40.2	Methyliumylidene	[CH]+ (g)	1619.753	1623.096	± 0.042	kJ/mol	13.01809 ± 0.00080	24361-82-8*0

Most Influential reactions involving CH (g, doublet)

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
1.000	2350.1	CH (g) → CH (g, doublet)	Δ_rH°(0 K) = 0 ± 0 cm-1	Botterud 1973, Huber 1979
0.434	2352.1	CH (g, doublet) → CH (g, quartet)	Δ_rH°(0 K) = 0.742 ± 0.008 eV	Kasdan 1975
0.113	5404.9	HCNN (g, doublet) → CH (g, doublet) + N2 (g)	Δ_rH°(0 K) = 126.88 ± 2.0 kJ/mol	Klippenstein 2017
0.045	2484.5	CH3C (g, doublet) + CH3 (g) → CH (g, doublet) + CH3CH2 (g)	Δ_rH°(0 K) = 15.92 ± 0.9 kcal/mol	Ruscic W1RO
0.044	2483.8	CH3C (g, doublet) + CH4 (g) → CH (g, doublet) + CH3CH3 (g)	Δ_rH°(0 K) = 19.72 ± 0.9 kcal/mol	Ruscic W1RO
0.037	2484.2	CH3C (g, doublet) + CH3 (g) → CH (g, doublet) + CH3CH2 (g)	Δ_rH°(0 K) = 15.91 ± 1.0 kcal/mol	Ruscic G4
0.037	2484.4	CH3C (g, doublet) + CH3 (g) → CH (g, doublet) + CH3CH2 (g)	Δ_rH°(0 K) = 15.18 ± 1.0 kcal/mol	Ruscic CBS-n
0.036	2483.7	CH3C (g, doublet) + CH4 (g) → CH (g, doublet) + CH3CH3 (g)	Δ_rH°(0 K) = 18.88 ± 1.0 kcal/mol	Ruscic CBS-n
0.036	2483.4	CH3C (g, doublet) + CH4 (g) → CH (g, doublet) + CH3CH3 (g)	Δ_rH°(0 K) = 19.88 ± 1.0 kcal/mol	Ruscic G4
0.030	2352.2	CH (g, doublet) → CH (g, quartet)	Δ_rH°(0 K) = 0.74 ± 0.03 eV	Goebbert 2012
0.030	2352.3	CH (g, doublet) → CH (g, quartet)	Δ_rH°(0 K) = 0.760 ± 0.030 eV	Kalemos 1999, est unc
0.030	2484.1	CH3C (g, doublet) + CH3 (g) → CH (g, doublet) + CH3CH2 (g)	Δ_rH°(0 K) = 15.68 ± 1.1 kcal/mol	Ruscic G3X
0.029	2483.3	CH3C (g, doublet) + CH4 (g) → CH (g, doublet) + CH3CH3 (g)	Δ_rH°(0 K) = 19.19 ± 1.1 kcal/mol	Ruscic G3X
0.021	2484.3	CH3C (g, doublet) + CH3 (g) → CH (g, doublet) + CH3CH2 (g)	Δ_rH°(0 K) = 15.31 ± 1.3 kcal/mol	Ruscic CBS-n
0.021	2483.6	CH3C (g, doublet) + CH4 (g) → CH (g, doublet) + CH3CH3 (g)	Δ_rH°(0 K) = 19.19 ± 1.3 kcal/mol	Ruscic CBS-n
0.014	2352.5	CH (g, doublet) → CH (g, quartet)	Δ_rH°(0 K) = 5897 ± 350 cm-1	Hettema 1994, est unc
0.011	5404.6	HCNN (g, doublet) → CH (g, doublet) + N2 (g)	Δ_rH°(0 K) = 29.47 ± 1.50 kcal/mol	Ruscic W1RO
0.011	5404.8	HCNN (g, doublet) → CH (g, doublet) + N2 (g)	Δ_rH°(0 K) = 29.6 ± 1.5 kcal/mol	Berman 2007, est unc
0.010	5404.7	HCNN (g, doublet) → CH (g, doublet) + N2 (g)	Δ_rH°(0 K) = 28.34 ± 1.2 (×1.297) kcal/mol	Harding 2008a, est unc
0.010	2351.8	CH (g, doublet) → CH (g, quartet)	Δ_rH°(0 K) = 6029 ± 420 cm-1	Ruscic W1RO

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 21^st 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. 1.130 of the Thermochemical Network. Argonne National Laboratory, Lemont, Illinois 2023; available at ATcT.anl.gov [DOI: 10.17038/CSE/1997229]
4		N. Genossar, P. B. Changala, B. Gans, J.-C. Loison, S. Hartweg, M.-A. Martin-Drumel, G. A. Garcia, J. F. Stanton, B. Ruscic, and J. H. Baraban Ring-Opening Dynamics of the Cyclopropyl Radical and Cation: the Transition State Nature of the Cyclopropyl Cation J. Am. Chem. Soc. 144, 18518-18525 (2022) [DOI: 10.1021/jacs.2c07740]
5		B. Ruscic and D. H. Bross Active Thermochemical Tables: The Thermophysical and Thermochemical Properties of Methyl, CH3, and Methylene, CH2, Corrected for Nonrigid Rotor and Anharmonic Oscillator Effects. Mol. Phys. e1969046 (2021) [DOI: 10.1080/00268976.2021.1969046]
6		J. H. Thorpe, J. L. Kilburn, D. Feller, P. B. Changala, D. H. Bross, B. Ruscic, and J. F. Stanton, Elaborated Thermochemical Treatment of HF, CO, N2, and H2O: Insight into HEAT and Its Extensions J. Chem. Phys. 155, 184109 (2021) [DOI: 10.1063/5.0069322]
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]
8		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]).
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.