Selected ATcT [1, 2] enthalpy of formation based on version 1.172 of the Thermochemical Network [3]

This version of ATcT results[3] was generated by additional expansion of version 1.156 to include species relevant to a study of photodissociation of formamide[4].

Methanethiol

Formula: CH3SH (cr,l)

CAS RN: 74-93-1

ATcT ID: 74-93-1*500

SMILES: CS

InChI: InChI=1S/CH4S/c1-2/h2H,1H3

InChIKey: LSDPWZHWYPCBBB-UHFFFAOYSA-N

Hills Formula: C1H4S1

2D Image:

Aliases: CH3SH; Methanethiol; Mercaptomethane; Methyl mercaptane; Methyl sulfhydrate; Methyl thioalcohol; UN 1064

Relative Molecular Mass: 48.1085 ± 0.0061

Δ_fH°(0 K)	Δ_fH°(298.15 K)	Uncertainty	Units
-46.76	-44.57	± 0.44	kJ/mol

Top contributors to the provenance of Δ_fH° of CH3SH (cr,l)

The 15 contributors listed below account for 90.0% of the provenance of Δ_fH° of CH3SH (cr,l).

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
63.8	9738.1	CH3SH (cr,l) + 7/2 O2 (g) → CO2 (g) + H2O (cr,l) + OS(O)(OH)2 (aq, 30 H2O)	Δ_rH°(298.15 K) = -363.49 ± 0.12 kcal/mol	Good 1961, Good 1961
4.0	9763.4	CH3SCH3 (g) + H2S (g) → 2 CH3SH (g)	Δ_rH°(0 K) = 3.52 ± 0.85 kcal/mol	Ruscic W1RO
3.5	9763.2	CH3SCH3 (g) + H2S (g) → 2 CH3SH (g)	Δ_rH°(0 K) = 3.54 ± 0.90 kcal/mol	Ruscic G4
3.5	9763.1	CH3SCH3 (g) + H2S (g) → 2 CH3SH (g)	Δ_rH°(0 K) = 3.60 ± 0.90 kcal/mol	Ruscic G3X
2.9	9763.3	CH3SCH3 (g) + H2S (g) → 2 CH3SH (g)	Δ_rH°(0 K) = 3.62 ± 1.00 kcal/mol	Ruscic CBS-n
2.4	9369.1	S (cr,l) + O2 (g) → OSO (g)	Δ_rH°(298.15 K) = -296.847 ± 0.200 kJ/mol	Eckman 1929, note SO2
1.7	9516.1	S (cr,l) + 3/2 O2 (g) + H2O (cr,l) → OS(O)(OH)2 (aq, 115 H2O)	Δ_rH°(298.15 K) = -143.85 ± 0.06 kcal/mol	Good 1960, CODATA Key Vals
1.6	9739.1	CH3SH (cr,l) → CH3SH (g)	Δ_rH°(298.15 K) = 24.01 ± 0.25 kJ/mol	ThermoData 2004
1.2	9516.2	S (cr,l) + 3/2 O2 (g) + H2O (cr,l) → OS(O)(OH)2 (aq, 115 H2O)	Δ_rH°(298.15 K) = -143.92 ± 0.07 kcal/mol	Mansson 1963, CODATA Key Vals
0.9	9736.4	CH3SH (g) + H2O (g) → CH3OH (g) + H2S (g)	Δ_rH°(0 K) = 10.43 ± 0.9 kcal/mol	Ruscic W1RO
0.9	9757.4	CH3CH2SH (g) + CH3CH3 (g) → CH3SH (g) + CH3CH2CH3 (g)	Δ_rH°(0 K) = 0.89 ± 0.85 kcal/mol	Ruscic W1RO
0.8	9758.4	CH3CH2SH (g) + CH3OH (g) → CH3SH (g) + CH3CH2OH (g)	Δ_rH°(0 K) = -2.15 ± 0.85 kcal/mol	Ruscic W1RO
0.8	9757.2	CH3CH2SH (g) + CH3CH3 (g) → CH3SH (g) + CH3CH2CH3 (g)	Δ_rH°(0 K) = 0.97 ± 0.90 kcal/mol	Ruscic G4
0.8	9757.1	CH3CH2SH (g) + CH3CH3 (g) → CH3SH (g) + CH3CH2CH3 (g)	Δ_rH°(0 K) = 1.09 ± 0.90 kcal/mol	Ruscic G3X
0.7	9758.1	CH3CH2SH (g) + CH3OH (g) → CH3SH (g) + CH3CH2OH (g)	Δ_rH°(0 K) = -2.10 ± 0.90 kcal/mol	Ruscic G3X

Top 10 species with enthalpies of formation correlated to the Δ_fH° of CH3SH (cr,l)

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
89.1	Methanethiol	CH3SH (g)	-10.39	-20.66	± 0.46	kJ/mol	48.1085 ± 0.0061	74-93-1*0
88.4	Methanethiol cation	[CH3SH]+ (g)	901.89	891.85	± 0.46	kJ/mol	48.1079 ± 0.0061	53369-41-8*0
28.2	Sulfuric acid	OS(O)(OH)2 (aq, 30 H2O)		-885.87	± 0.13	kJ/mol	98.0795 ± 0.0061	7664-93-9*820
28.2	Sulfuric acid	OS(O)(OH)2 (aq, 100 H2O)		-887.53	± 0.13	kJ/mol	98.0795 ± 0.0061	7664-93-9*828
28.2	Sulfuric acid	OS(O)(OH)2 (aq, 40 H2O)		-886.35	± 0.13	kJ/mol	98.0795 ± 0.0061	7664-93-9*821
28.2	Sulfuric acid	OS(O)(OH)2 (aq, 75 H2O)		-887.18	± 0.13	kJ/mol	98.0795 ± 0.0061	7664-93-9*825
28.2	Sulfuric acid	OS(O)(OH)2 (aq, 50 H2O)		-886.66	± 0.13	kJ/mol	98.0795 ± 0.0061	7664-93-9*822
28.2	Sulfuric acid	OS(O)(OH)2 (aq, 1000 H2O)		-892.23	± 0.13	kJ/mol	98.0795 ± 0.0061	7664-93-9*839
28.2	Sulfuric acid	OS(O)(OH)2 (aq, 800 H2O)		-891.62	± 0.13	kJ/mol	98.0795 ± 0.0061	7664-93-9*837
28.2	Sulfuric acid	OS(O)(OH)2 (aq, 700 H2O)		-891.25	± 0.13	kJ/mol	98.0795 ± 0.0061	7664-93-9*835

Most Influential reactions involving CH3SH (cr,l)

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
0.699	9738.1	CH3SH (cr,l) + 7/2 O2 (g) → CO2 (g) + H2O (cr,l) + OS(O)(OH)2 (aq, 30 H2O)	Δ_rH°(298.15 K) = -363.49 ± 0.12 kcal/mol	Good 1961, Good 1961
0.696	9739.1	CH3SH (cr,l) → CH3SH (g)	Δ_rH°(298.15 K) = 24.01 ± 0.25 kJ/mol	ThermoData 2004
0.248	9739.2	CH3SH (cr,l) → CH3SH (g)	Δ_rH°(279.12 K) = 5.872 ± 0.10 kcal/mol	Russell 1942, Good 1961, Good 1961, est unc

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. 1.172 of the Thermochemical Network (2024); available at ATcT.anl.gov
4		K. L. Caster, N. A. Seifert, B. Ruscic, A. W. Jasper, and K. Prozument, Dynamics of HCN, NHC, and HNCO Formation in the 193 nm Photodissociation of Formamide J. Phys. Chem. A (in press) (2024) [DOI: 10.1021/acs.jpca.4c02232]
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.