Selected ATcT [1, 2] enthalpy of formation based on version 1.202 of the Thermochemical Network [3]

This version of ATcT results[3] was generated by additional expansion of version 1.176 in order to include species related to the thermochemistry of glycine[4].

Methoxide

Formula: [CH3O]- (g)

CAS RN: 3315-60-4

ATcT ID: 3315-60-4*0

SMILES: C[O-]

InChI: InChI=1S/CH3O/c1-2/h1H3/q-1

InChIKey: NBTOZLQBSIZIKS-UHFFFAOYSA-N

Hills Formula: C1H3O1-

2D Image:

Aliases: [CH3O]-; Methoxide; Methoxide ion; Methoxyde; Methanolate; Methanolate anion; Methanolate ion (1-); Methoxide anion; Methoxide ion (1-); Methoxyde anion; Methoxyde ion (1-); Methoxy anion; Methoxy ion (1-); Methylate; CH3O-; [H3CO]-; H3CO-; [CH3(O)]-; CH3(O)-

Relative Molecular Mass: 31.03447 ± 0.00088

Δ_fH°(0 K)	Δ_fH°(298.15 K)	Uncertainty	Units
-122.41	-130.13	± 0.26	kJ/mol

3D Image of [CH3O]- (g)

spin ON spin OFF

Top contributors to the provenance of Δ_fH° of [CH3O]- (g)

The 20 contributors listed below account only for 43.1% of the provenance of Δ_fH° of [CH3O]- (g).
A total of 437 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
7.8	2986.9	CH3OH (g) → CH3O (g) + H (g)	Δ_rH°(0 K) = 104.06 ± 0.17 kcal/mol	Nguyen 2015a
5.7	3015.10	CH2OH (g) → CH3O (g)	Δ_rH°(0 K) = 9.47 ± 0.17 kcal/mol	Nguyen 2015a
3.8	2993.1	CH3O (g) → CH3 (g) + O (g)	Δ_rH°(0 K) = 87.8 ± 0.3 kcal/mol	Osborn 1995, Osborn 1997
3.0	2991.1	CH3OH (g) + F- (g) → [CH3O]- (g) + HF (g)	Δ_rH°(0 K) = 0.462 ± 0.003 (×4.177) eV	DeTuri 1999, Ervin 2002
2.9	2958.2	CH3OH (g) + 3/2 O2 (g) → CO2 (g) + 2 H2O (cr,l)	Δ_rH°(298.15 K) = -182.72 ± 0.05 (×1.269) kcal/mol	Rossini 1932a, Domalski 1972, Weltner 1951, Rossini 1934a, note old units, mw conversion
2.5	7022.1	[C6H5CH2]- (g) → C6H5CH2 (g)	Δ_rH°(0 K) = 0.912 ± 0.006 eV	Gunion 1992
2.0	2982.2	[CH3O]- (g) → CH3O (g)	Δ_rH°(0 K) = 12654 ± 6 cm-1	Weichman 2017
1.7	2994.1	CH3O (g) → CH2O (g) + H (g)	Δ_rH°(0 K) = 6950 ± 150 cm-1	Dertinger 1995
1.5	2993.10	CH3O (g) → CH3 (g) + O (g)	Δ_rH°(0 K) = 366.45 ± 2 kJ/mol	Marenich 2006, est unc
1.4	2984.9	[CH3O]- (g) → C (g) + 3 H (g) + O (g)	Δ_rH°(0 K) = 413.01 ± 0.50 kcal/mol	Matus 2007
1.4	2980.11	CH3O (g) → C (g) + 3 H (g) + O (g)	Δ_rH°(0 K) = 376.52 ± 0.3 (×1.61) kcal/mol	Feller 2008
1.3	2980.10	CH3O (g) → C (g) + 3 H (g) + O (g)	Δ_rH°(0 K) = 376.49 ± 0.50 (×1.022) kcal/mol	Matus 2007
1.3	2994.10	CH3O (g) → CH2O (g) + H (g)	Δ_rH°(0 K) = 79.62 ± 2 (×1.044) kJ/mol	Marenich 2006, est unc
1.0	2980.9	CH3O (g) → C (g) + 3 H (g) + O (g)	Δ_rH°(0 K) = 1574.97 ± 2 (×1.215) kJ/mol	Marenich 2006, est unc
1.0	2987.9	CH3OH (g) → [CH3O]- (g) + H+ (g)	Δ_rH°(0 K) = 381.8 ± 0.50 kcal/mol	Matus 2007
0.9	2986.10	CH3OH (g) → CH3O (g) + H (g)	Δ_rH°(0 K) = 436.14 ± 2 kJ/mol	Marenich 2006, est unc
0.9	2994.11	CH3O (g) → CH2O (g) + H (g)	Δ_rH°(0 K) = 6653 ± 200 cm-1	Kamarchik 2012, est unc
0.8	3008.1	[CH2OH]+ (g) → CH2O (g) + H+ (g)	Δ_rH°(0 K) = 704.98 ± 0.39 kJ/mol	Czako 2009
0.7	2983.9	[CH3O]+ (g) → C (g) + 3 H (g) + O (g)	Δ_rH°(0 K) = 129.93 ± 0.50 kcal/mol	Matus 2007
0.6	3015.11	CH2OH (g) → CH3O (g)	Δ_rH°(0 K) = 9.62 ± 0.50 kcal/mol	Matus 2007

Top 10 species with enthalpies of formation correlated to the Δ_fH° of [CH3O]- (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	Δ_fH°(0 K)	Δ_fH°(298.15 K)	Uncertainty	Units	Relative Molecular Mass	ATcT ID
96.9	Methoxy	CH3O (g)	28.98	21.61	± 0.26	kJ/mol	31.03392 ± 0.00088	2143-68-2*0
53.4	Benzylide	[C6H5CH2]- (g)	142.01	123.10	± 0.40	kJ/mol	91.1310 ± 0.0056	18860-15-6*0
36.4	Methanol	CH3OH (g)	-189.96	-200.84	± 0.14	kJ/mol	32.04186 ± 0.00090	67-56-1*0
35.5	Methanol	CH3OH (cr,l)	-235.20	-238.54	± 0.15	kJ/mol	32.04186 ± 0.00090	67-56-1*500
33.6	Methyloxoniumylidene	[CH3O]+ (g)	1062.72	1054.91	± 0.57	kJ/mol	31.03337 ± 0.00088	58157-09-8*0
28.9	Hydroxymethyl	CH2OH (g)	-10.10	-16.41	± 0.28	kJ/mol	31.03392 ± 0.00088	2597-43-5*0
26.8	Hydroxymethylium	[CH2OH]+ (g)	717.75	709.81	± 0.18	kJ/mol	31.03337 ± 0.00088	18682-95-6*0
23.0	Benzyl	C6H5CH2 (g)	230.16	211.35	± 0.51	kJ/mol	91.1305 ± 0.0056	2154-56-5*0
22.8	Benzylium	[C6H5CH2]+ (g)	929.58	910.09	± 0.51	kJ/mol	91.1299 ± 0.0056	6711-19-9*0
20.1	Ethoxy	CH3CH2O (g, X 2A")	1.39	-12.51	± 0.42	kJ/mol	45.0605 ± 0.0017	2154-50-9*51

Most Influential reactions involving [CH3O]- (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
0.988	7030.2	[C6H5CH2]- (g) + CH3OH (g) → C6H5CH3 (g) + [CH3O]- (g)	Δ_rG°(300 K) = 0.16 ± 0.02 kcal/mol	Ellison 1996
0.805	2982.2	[CH3O]- (g) → CH3O (g)	Δ_rH°(0 K) = 12654 ± 6 cm-1	Weichman 2017
0.289	3859.1	CH3CHCCH2 (g) + [CH3O]- (g) → [CH3CCCH2]- (g) + CH3OH (g)	Δ_rG°(298.15 K) = 5 ± 2 kJ/mol	de Visser 1999, est unc
0.219	8960.5	SiH(CH3)3 (g) + [CH3O]- (g) → [Si(CH3)3]- (g) + CH3OH (g)	Δ_rH°(0 K) = 4.26 ± 0.8 kcal/mol	Ruscic W1RO
0.148	2844.3	CH3NC (g) + [CH3O]- (g) → [CH2NC]- (g) + CH3OH (g)	Δ_rG°(300 K) = -0.93 ± 0.5 kcal/mol	Matimba 1992, est unc
0.140	8960.3	SiH(CH3)3 (g) + [CH3O]- (g) → [Si(CH3)3]- (g) + CH3OH (g)	Δ_rH°(0 K) = 3.31 ± 1.0 kcal/mol	Ruscic G4
0.128	2982.1	[CH3O]- (g) → CH3O (g)	Δ_rH°(0 K) = 12655 ± 15 cm-1	Nee 2006
0.107	8277.5	[CH2CCN]- (g) + CH3OH (g) → CH2CHCN (g, singlet) + [CH3O]- (g)	Δ_rH°(0 K) = 8.79 ± 0.8 kcal/mol	Ruscic W1RO
0.097	8960.2	SiH(CH3)3 (g) + [CH3O]- (g) → [Si(CH3)3]- (g) + CH3OH (g)	Δ_rH°(0 K) = 2.76 ± 1.2 kcal/mol	Ruscic G3X
0.082	8960.4	SiH(CH3)3 (g) + [CH3O]- (g) → [Si(CH3)3]- (g) + CH3OH (g)	Δ_rH°(0 K) = 3.92 ± 1.3 kcal/mol	Ruscic CBS-n
0.082	3017.8	[CH2OH]- (g) → [CH3O]- (g)	Δ_rH°(0 K) = -31.50 ± 1.2 kcal/mol	Ruscic W1RO
0.082	3017.7	[CH2OH]- (g) → [CH3O]- (g)	Δ_rH°(0 K) = -31.86 ± 1.2 kcal/mol	Ruscic CBS-n
0.069	3017.4	[CH2OH]- (g) → [CH3O]- (g)	Δ_rH°(0 K) = -31.57 ± 1.3 kcal/mol	Ruscic G4
0.068	8277.4	[CH2CCN]- (g) + CH3OH (g) → CH2CHCN (g, singlet) + [CH3O]- (g)	Δ_rH°(0 K) = 8.88 ± 1.0 kcal/mol	Ruscic CBS-n
0.068	8277.2	[CH2CCN]- (g) + CH3OH (g) → CH2CHCN (g, singlet) + [CH3O]- (g)	Δ_rH°(0 K) = 8.83 ± 1.0 kcal/mol	Ruscic G4
0.065	4184.1	[CH3CH2O]- (g) + CH3OH (g) → [CH3O]- (g) + CH3CH2OH (g)	Δ_rH°(0 K) = 0.129 ± 0.004 (×4.362) eV	DeTuri 1999, Ervin 2002
0.060	3017.3	[CH2OH]- (g) → [CH3O]- (g)	Δ_rH°(0 K) = -31.30 ± 1.4 kcal/mol	Ruscic G3X
0.058	2844.8	CH3NC (g) + [CH3O]- (g) → [CH2NC]- (g) + CH3OH (g)	Δ_rH°(0 K) = 0.55 ± 0.8 kcal/mol	Ruscic W1RO
0.054	4626.5	[CH2(OH)O]- (g, syn) + CH3OH (g) → CH2(OH)2 (g, C2 gauche) + [CH3O]- (g)	Δ_rH°(0 K) = 15.43 ± 0.8 kcal/mol	Ruscic W1RO
0.053	3544.1	CH2CCH2 (g) + [CH3O]- (g) → CH3OH (g) + [CH2CCH]- (g)	Δ_rG°(298.15 K) = -2.10 ± 0.35 (×1.957) kcal/mol	Robinson 1995

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. 1.202 of the Thermochemical Network (2024); available at ATcT.anl.gov
4		B. Ruscic and D. H. Bross Accurate and Reliable Thermochemistry by Data Analysis of Complex Thermochemical Networks using Active Thermochemical Tables: The Case of Glycine Thermochemistry Faraday Discuss. (in press) (2024) [DOI: 10.1039/D4FD00110A]
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.