Selected ATcT [1, 2] enthalpy of formation based on version 1.124 of the Thermochemical Network [3]

This version of ATcT results was generated by additional expansion of version 1.122x [4] to include additional information relevant to the study of thermophysical and thermochemical properties of CH2 and CH3 using nonrigid rotor anharmonic oscillator (NRRAO) partition functions [5], the development and benchmarking of a state-of-the-art computational approach that aims to reproduce total atomization energies of small molecules within 10–15 cm^-1 [6], as well as the study of the reversible reaction C₂H₃ + H₂ ⇌ C₂H₄ + H ⇌ C₂H₅ [7]

Carbon

Formula: C (g, triplet)

CAS RN: 7440-44-0

ATcT ID: 7440-44-0*1

SMILES: [C]

InChI: InChI=1S/C

InChIKey: OKTJSMMVPCPJKN-UHFFFAOYSA-N

Hills Formula: C1

2D Image:

Aliases: C; Carbon; Carbon atom; Atomic carbon; Carbon radical; Monocarbon; C-atom; C g; C gas; C g, triplet; C g, triplet only; C g, singlet; C g, singlet only; C g,triplet; C g,triplet only; C g,singlet; C g,singlet only

Relative Molecular Mass: 12.01070 ± 0.00080

Δ_fH°(0 K)	Δ_fH°(298.15 K)	Uncertainty	Units
711.404	716.889	± 0.044	kJ/mol

3D Image of C (g, triplet)

spin ON spin OFF

Top contributors to the provenance of Δ_fH° of C (g, triplet)

The 20 contributors listed below account only for 32.4% of the provenance of Δ_fH° of C (g, triplet).
A total of 999 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
6.9	2149.2	CO (g) → C+ (g) + O (g)	Δ_rH°(0 K) = 22.3713 ± 0.0015 eV	Ng 2007
5.6	2245.1	2 H2 (g) + C (graphite) → CH4 (g)	Δ_rG°(1165 K) = 37.521 ± 0.068 kJ/mol	Smith 1946, note COf, 3rd Law
3.4	120.2	1/2 O2 (g) + H2 (g) → H2O (cr,l)	Δ_rH°(298.15 K) = -285.8261 ± 0.040 kJ/mol	Rossini 1939, Rossini 1931, Rossini 1931b, note H2Oa, Rossini 1930
2.0	2101.7	C (graphite) + O2 (g) → CO2 (g)	Δ_rH°(298.15 K) = -393.464 ± 0.024 kJ/mol	Hawtin 1966, note CO2e
1.8	2157.5	C (graphite) + CO2 (g) → 2 CO (g)	Δ_rG°(1165 K) = -33.545 ± 0.058 kJ/mol	Smith 1946, note COf, 3rd Law
1.4	2136.5	CO (g) → C (g) + O (g)	Δ_rH°(0 K) = 89632 ± 27 cm-1	Ruscic 2003
1.2	6071.8	C6H6 (g) → 6 C (g) + 6 H (g)	Δ_rH°(0 K) = 5463.0 ± 1.8 kJ/mol	Harding 2011
1.2	2134.3	CO (g) → C (g) + O (g)	Δ_rH°(0 K) = 89620 ± 29 cm-1	Douglas 1955, Schmid 1935, note COj
1.0	7959.1	C60 (cr,l) + 60 O2 (g) → 60 CO2 (g)	Δ_rH°(298.15 K) = -25965 ± 20 kJ/mol	Kolesov 1996, est unc
1.0	2397.1	CH2CH2 (g) + 3 O2 (g) → 2 CO2 (g) + 2 H2O (cr,l)	Δ_rH°(298.15 K) = -1411.18 ± 0.30 kJ/mol	Rossini 1937
0.9	6071.5	C6H6 (g) → 6 C (g) + 6 H (g)	Δ_rH°(0 K) = 1305.43 ± 0.50 kcal/mol	Karton 2017
0.8	2101.4	C (graphite) + O2 (g) → CO2 (g)	Δ_rH°(298.15 K) = -393.462 ± 0.038 kJ/mol	Lewis 1965, note CO2d
0.8	2101.5	C (graphite) + O2 (g) → CO2 (g)	Δ_rH°(298.15 K) = -393.468 ± 0.038 kJ/mol	Fraser 1952, note CO2f
0.6	6071.4	C6H6 (g) → 6 C (g) + 6 H (g)	Δ_rH°(0 K) = 1306.17 ± 0.60 kcal/mol	Karton 2009a
0.5	2101.10	C (graphite) + O2 (g) → CO2 (g)	Δ_rH°(298.15 K) = -94.051 ± 0.011 kcal/mol	Prosen 1944a, Cox 1970, NBS TN270, NBS Tables 1989
0.5	3472.9	CH3CH2CH2CH3 (g) → 4 C (g) + 10 H (g)	Δ_rH°(0 K) = 1220.02 ± 0.35 kcal/mol	Karton 2017
0.5	2105.7	CO2 (g) → C (g) + 2 O (g)	Δ_rH°(0 K) = 1598.16 ± 0.56 kJ/mol	Harding 2008
0.5	3704.6	CH3CH2CH2CH2CH3 (g) → 5 C (g) + 12 H (g)	Δ_rH°(0 K) = 1496.83 ± 0.50 kcal/mol	Karton 2017
0.4	6483.6	N(CHCHCHCHCH) (g) → 5 C (g) + N (g) + 5 H (g)	Δ_rH°(0 K) = 1183.35 ± 0.60 kcal/mol	Karton 2009a
0.4	3246.1	CH3CCH (g) + 4 O2 (g) → 3 CO2 (g) + 2 H2O (cr,l)	Δ_rH°(298.15 K) = -463.131 ± 0.204 kcal/mol	Wagman 1945, Wagman 1945a

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

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	Carbon	C (g)	711.404	716.889	± 0.044	kJ/mol	12.01070 ± 0.00080	7440-44-0*0
99.9	Carbon	C (g, quintuplet)	1114.967	1120.114	± 0.044	kJ/mol	12.01070 ± 0.00080	7440-44-0*3
99.9	Carbon	C (g, singlet)	833.335	838.482	± 0.044	kJ/mol	12.01070 ± 0.00080	7440-44-0*2
99.9	Carbon cation	C+ (g)	1797.857	1803.455	± 0.044	kJ/mol	12.01015 ± 0.00080	14067-05-1*0
99.9	Carbon dication	[C]+2 (g)	4150.474	4155.620	± 0.044	kJ/mol	12.00960 ± 0.00080	16092-61-8*0
99.6	Carbon anion	C- (g)	589.628	594.774	± 0.044	kJ/mol	12.01125 ± 0.00080	14337-00-9*0
95.1	Ethynylene	C2 (g)	820.005	828.470	± 0.092	kJ/mol	24.0214 ± 0.0016	12070-15-4*0
95.1	Ethynylene	C2 (g, singlet)	820.005	826.577	± 0.092	kJ/mol	24.0214 ± 0.0016	12070-15-4*2
95.1	Ethynylene	C2 (g, triplet)	827.228	833.933	± 0.092	kJ/mol	24.0214 ± 0.0016	12070-15-4*1
87.7	Carbon trication	[C]+3 (g)	8770.942	8776.088	± 0.050	kJ/mol	12.00905 ± 0.00080	14067-06-2*0

Most Influential reactions involving C (g, triplet)

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	2098.1	C (g, triplet) → C (g)	Δ_rH°(0 K) = 0 ± 0 cm-1	triv
1.000	2100.1	C (g, triplet) → C (g, quintuplet)	Δ_rH°(0 K) = 33735.22 ± 0.05 cm-1	Sansonetti 2005, Johansson 1966, NSRDS-NBS 35, est unc
1.000	2099.1	C (g, triplet) → C (g, singlet)	Δ_rH°(0 K) = 10192.63 ± 0.05 cm-1	NIST Atomic Web, est unc
0.046	5168.10	NCN (g) → N2 (g) + C (g, triplet)	Δ_rH°(0 K) = 260.62 ± 2.0 kJ/mol	Klippenstein 2017
0.004	5168.8	NCN (g) → N2 (g) + C (g, triplet)	Δ_rH°(0 K) = 2.693 ± 0.065 eV	Ruscic W1RO
0.002	5168.6	NCN (g) → N2 (g) + C (g, triplet)	Δ_rH°(0 K) = 2.784 ± 0.094 eV	Ruscic CBS-n
0.000	5168.1	NCN (g) → N2 (g) + C (g, triplet)	Δ_rH°(0 K) = 2.541 ± 0.030 (×5.187) eV	Bise 1999

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. 1.124 of the Thermochemical Network, Argonne National Laboratory, Lemont, Illinois 2022; available at ATcT.anl.gov [DOI: 10.17038/CSE/1885923]
4		Y. Ren, L. Zhou, A. Mellouki, V. Daële, M. Idir, S. S. Brown, B. Ruscic, Robert S. Paton, M. R. McGillen, and A. R. Ravishankara, Reactions of NO3 with Aromatic Aldehydes: Gas-Phase Kinetics and Insights into the Mechanism of the Reaction. Atmos. Chem. Phys. 21, 13537-13551 (2021) [DOI: 10.5194/acp2021-228]
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		T. L. Nguyen, D. H. Bross, B. Ruscic, G. B. Ellison, and J. F. Stanton, Mechanism, Thermochemistry, and Kinetics of the Reversible Reactions: C2H3 + H2 ⇌ C2H4 + H ⇌ C2H5. Faraday Discuss. , (Advance Article) (2022) [DOI: 10.1039/D1FD00124H]
8		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]
9		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 [8,9]).
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.