Selected ATcT [1, 2] enthalpy of formation based on version 1.176 of the Thermochemical Network [3]

This version of ATcT results[3] was generated by additional expansion of version 1.172 to include species related to Criegee intermediates that are involved in several ongoing studies[4].

Methylidyne

Formula: CH (g, quartet)
CAS RN: 3315-37-5
ATcT ID: 3315-37-5*2
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
664.70668.03± 0.52kJ/mol

3D Image of CH (g, quartet)

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

The 20 contributors listed below account only for 81.2% of the provenance of ΔfH° of CH (g, quartet).
A total of 43 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
42.32449.1 CH (g, doublet) → CH (g, quartet) ΔrH°(0 K) = 0.742 ± 0.008 eVKasdan 1975
18.05686.3 NCN (g) H (g) → CH (g, quartet) N2 (g) ΔrH°(0 K) = -2.20 ± 1.0 kJ/molHarding 2018
3.02449.3 CH (g, doublet) → CH (g, quartet) ΔrH°(0 K) = 0.760 ± 0.030 eVKalemos 1999, est unc
3.02449.2 CH (g, doublet) → CH (g, quartet) ΔrH°(0 K) = 0.74 ± 0.03 eVGoebbert 2012
2.25978.1 CH (g, quartet) N2 (g) → HCN (g) N (g, quartet) ΔrH°(0 K) = -15.28 ± 0.8 kcal/molHarding 2008a, est unc
1.42449.5 CH (g, doublet) → CH (g, quartet) ΔrH°(0 K) = 5897 ± 350 cm-1Hettema 1994, est unc
1.12450.1 [CH]- (g) → CH (g, quartet) ΔrH°(0 K) = 1.94 ± 0.05 eVFeldmann 1970
1.02441.9 CH (g, quartet) → C (g) H (g) ΔrH°(0 K) = 2.671 ± 0.045 (×1.164) eVKalemos 1999, est unc
0.92448.8 CH (g, doublet) → CH (g, quartet) ΔrH°(0 K) = 6029 ± 420 cm-1Ruscic W1RO
0.82448.4 CH (g, doublet) → CH (g, quartet) ΔrH°(0 K) = 6152 ± 450 cm-1Ruscic G4
0.82448.7 CH (g, doublet) → CH (g, quartet) ΔrH°(0 K) = 6159 ± 455 cm-1Ruscic CBS-n
0.85716.1 HNCN (g, doublet) → CH (g, quartet) N2 (g) ΔrH°(0 K) = 81.01 ± 1.2 kcal/molHarding 2008a, est unc
0.72448.3 CH (g, doublet) → CH (g, quartet) ΔrH°(0 K) = 5843 ± 490 cm-1Ruscic G3X
0.75748.1 HCNN (g, doublet) → CH (g, quartet) N2 (g) ΔrH°(0 K) = 45.79 ± 1.1 (×1.164) kcal/molHarding 2008a, est unc
0.75786.1 HNNC (g, doublet) → CH (g, quartet) N2 (g) ΔrH°(0 K) = 41.13 ± 1.2 kcal/molHarding 2008a, est unc
0.65674.10 NCN (g) → 2 N (g) C (g) ΔrH°(0 K) = 1200.9 ± 1.0 kJ/molHarding 2018
0.65687.4 NCN (g) H (g) → HCN (g) N (g) ΔrH°(0 K) = -67.10 ± 1.0 kJ/molHarding 2018
0.62441.8 CH (g, quartet) → C (g) H (g) ΔrH°(0 K) = 62.83 ± 1.50 kcal/molRuscic W1RO
0.62449.9 CH (g, doublet) → CH (g, quartet) ΔrH°(0 K) = 17.45 ± 1.5 kcal/molHarding 2008a, est unc
0.62449.6 CH (g, doublet) → CH (g, quartet) ΔrH°(0 K) = 5671 ± 525 cm-1Follmeg 1987, est unc

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

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
26.2 EthylidyneCH3C (g, quartet)[C]C640.8636.3± 1.1kJ/mol27.0452 ±
0.0016
67624-57-1*2
21.6 MethanetetraylbisamidogenNCN (g)[N]=C=[N]451.36451.77± 0.40kJ/mol40.02418 ±
0.00081
2669-76-3*0
15.3 PropylidyneCH3CH2C (g, quartet)CC[C]624.8613.3± 1.3kJ/mol41.0718 ±
0.0024
85056-54-8*2
14.4 Cyanoamidogen anion[NCN]- (g)[N]=[C-]=[N]211.85211.77± 0.60kJ/mol40.02473 ±
0.00081
189879-95-6*0
11.7 DiazomethylHCNN (g, quartet)[CH]=[N]=[N]652.7649.8± 1.3kJ/mol41.03212 ±
0.00082
20813-32-5*2
11.7 DiazomethylHCNN (g, c-quartet)[CH]=[N]=[N]652.7649.7± 1.3kJ/mol41.03212 ±
0.00082
20813-32-5*22
11.6 MethylidyneCH (g, doublet)[CH]592.967596.301± 0.081kJ/mol13.01864 ±
0.00080
3315-37-5*1
11.6 MethylidyneCH (g)[CH]592.967596.301± 0.081kJ/mol13.01864 ±
0.00080
3315-37-5*0
11.6 IsocyanoamidogenHNNC (g, c-quartet)[NH][N+]#[C-]828.2825.4± 1.3kJ/mol41.03212 ±
0.00082
947408-73-3*22
11.6 IsocyanoamidogenHNNC (g, quartet)[NH][N+]#[C-]828.2825.6± 1.3kJ/mol41.03212 ±
0.00082
947408-73-3*2

Most Influential reactions involving CH (g, quartet)

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
0.4332449.1 CH (g, doublet) → CH (g, quartet) ΔrH°(0 K) = 0.742 ± 0.008 eVKasdan 1975
0.3335686.3 NCN (g) H (g) → CH (g, quartet) N2 (g) ΔrH°(0 K) = -2.20 ± 1.0 kJ/molHarding 2018
0.0742583.5 CH3C (g, quartet) CH3 (g) → CH (g, quartet) CH3CH2 (g) ΔrH°(0 K) = 1.21 ± 0.9 kcal/molRuscic W1RO
0.0732582.5 CH3C (g, quartet) CH4 (g) → CH (g, quartet) CH3CH3 (g) ΔrH°(0 K) = 5.01 ± 0.9 kcal/molRuscic W1RO
0.0602583.4 CH3C (g, quartet) CH3 (g) → CH (g, quartet) CH3CH2 (g) ΔrH°(0 K) = 1.56 ± 1.0 kcal/molRuscic CBS-n
0.0602583.2 CH3C (g, quartet) CH3 (g) → CH (g, quartet) CH3CH2 (g) ΔrH°(0 K) = 1.33 ± 1.0 kcal/molRuscic G4
0.0592582.2 CH3C (g, quartet) CH4 (g) → CH (g, quartet) CH3CH3 (g) ΔrH°(0 K) = 5.30 ± 1.0 kcal/molRuscic G4
0.0592582.4 CH3C (g, quartet) CH4 (g) → CH (g, quartet) CH3CH3 (g) ΔrH°(0 K) = 5.26 ± 1.0 kcal/molRuscic CBS-n
0.0575786.1 HNNC (g, doublet) → CH (g, quartet) N2 (g) ΔrH°(0 K) = 41.13 ± 1.2 kcal/molHarding 2008a, est unc
0.0502583.1 CH3C (g, quartet) CH3 (g) → CH (g, quartet) CH3CH2 (g) ΔrH°(0 K) = 1.11 ± 1.1 kcal/molRuscic G3X
0.0492582.1 CH3C (g, quartet) CH4 (g) → CH (g, quartet) CH3CH3 (g) ΔrH°(0 K) = 4.62 ± 1.1 kcal/molRuscic G3X
0.0445749.5 HCNN (g, c-quartet) → CH (g, quartet) N2 (g) ΔrH°(0 K) = 3.08 ± 1.50 kcal/molRuscic W1RO
0.0405787.5 HNNC (g, c-quartet) → CH (g, quartet) N2 (g) ΔrH°(0 K) = -39.59 ± 1.50 kcal/molRuscic W1RO
0.0395719.5 HNCN (g, t-quartet) → CH (g, quartet) N2 (g) ΔrH°(0 K) = 2.92 ± 1.50 kcal/molRuscic W1RO
0.0385749.4 HCNN (g, c-quartet) → CH (g, quartet) N2 (g) ΔrH°(0 K) = 4.41 ± 1.60 kcal/molRuscic CBS-n
0.0385749.2 HCNN (g, c-quartet) → CH (g, quartet) N2 (g) ΔrH°(0 K) = 1.84 ± 1.60 kcal/molRuscic G4
0.0352583.3 CH3C (g, quartet) CH3 (g) → CH (g, quartet) CH3CH2 (g) ΔrH°(0 K) = 1.58 ± 1.3 kcal/molRuscic CBS-n
0.0355787.2 HNNC (g, c-quartet) → CH (g, quartet) N2 (g) ΔrH°(0 K) = -39.90 ± 1.60 kcal/molRuscic G4
0.0352582.3 CH3C (g, quartet) CH4 (g) → CH (g, quartet) CH3CH3 (g) ΔrH°(0 K) = 5.46 ± 1.3 kcal/molRuscic CBS-n
0.0345719.2 HNCN (g, t-quartet) → CH (g, quartet) N2 (g) ΔrH°(0 K) = 2.16 ± 1.60 kcal/molRuscic G4


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. 1.176 of the Thermochemical Network (2024); available at ATcT.anl.gov
4   T. L. Nguyen et al, ongoing studies (2024)
5   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]
6   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 [5] and Ruscic and Bross[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.