Selected ATcT [1, 2] enthalpy of formation based on version 1.156 of the Thermochemical Network [3]

This version of ATcT results[3] was generated by additional expansion of version 1.148 to include species relevant to a recent study of the oxidation of ethylene [4] as well as new measurements that led to refining the thermochemistry of CF and SiF and their cations [5].

Methoxyoxoniumylidene

Formula: [CH3OO]+ (g)

CAS RN: 86475-50-5

ATcT ID: 86475-50-5*0

SMILES: CO[O+]

InChI: InChI=1S/CH3O2/c1-3-2/h1H3/q+1

InChIKey: HRUCYOXWRHWOMG-UHFFFAOYSA-N

Hills Formula: C1H3O2+

2D Image:

Aliases: [CH3OO]+; Methoxyoxoniumylidene; 1-Methyldioxiden-1-ium; Methoxyoxoniumylidene ion; Methoxyoxoniumylidene cation; Methoxyoxoniumylidene ion (1+); Methylperoxy cation; Methylperoxy ion (1+); Methyldioxy cation; Methyldioxy ion (1+); Methylperoxyl cation; Methylperoxyl ion (1+); Methylperoxo cation; Methylperoxo ion (1+); CH3OO+

Relative Molecular Mass: 47.0328 ± 0.0010

Δ_fH°(0 K)	Δ_fH°(298.15 K)	Uncertainty	Units
1012.32	1003.49	± 0.67	kJ/mol

3D Image of [CH3OO]+ (g)

spin ON spin OFF

Top contributors to the provenance of Δ_fH° of [CH3OO]+ (g)

The 10 contributors listed below account for 90.7% of the provenance of Δ_fH° of [CH3OO]+ (g).

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
44.3	4568.9	[CH3OO]+ (g) → C (g) + 3 H (g) + 2 O (g)	Δ_rH°(0 K) = 840.85 ± 1. kJ/mol	Welch 2019, Welch 2018
35.5	4566.13	CH3OO (g) → [CH3OO]+ (g)	Δ_rH°(0 K) = 10.259 ± 0.010 eV	Welch 2019, Welch 2018
2.2	4566.11	CH3OO (g) → [CH3OO]+ (g)	Δ_rH°(0 K) = 10.274 ± 0.040 eV	Ruscic W1RO
1.8	4566.1	CH3OO (g) → [CH3OO]+ (g)	Δ_rH°(0 K) = 10.215 ± 0.015 (×2.954) eV	Tang 2020a
1.6	4578.6	CH3OO (g) → CH3 (g) + O2 (g)	Δ_rH°(0 K) = 30.40 ± 0.17 kcal/mol	Nguyen 2014a
1.4	4566.2	CH3OO (g) → [CH3OO]+ (g)	Δ_rH°(0 K) = 10.265 ± 0.050 eV	Voronova 2018, Tang 2020a, est unc
1.1	4568.8	[CH3OO]+ (g) → C (g) + 3 H (g) + 2 O (g)	Δ_rH°(0 K) = 200.52 ± 1.50 kcal/mol	Ruscic W1RO
0.9	4568.4	[CH3OO]+ (g) → C (g) + 3 H (g) + 2 O (g)	Δ_rH°(0 K) = 201.00 ± 1.60 kcal/mol	Ruscic G4
0.8	4568.3	[CH3OO]+ (g) → C (g) + 3 H (g) + 2 O (g)	Δ_rH°(0 K) = 200.96 ± 1.72 kcal/mol	Ruscic G3X
0.8	4565.9	CH3OO (g) → C (g) + 3 H (g) + 2 O (g)	Δ_rH°(0 K) = 1830.74 ± 1. kJ/mol	Welch 2019, Welch 2018

Top 10 species with enthalpies of formation correlated to the Δ_fH° of [CH3OO]+ (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
27.7	Methylperoxy	CH3OO (g)	22.52	13.07	± 0.34	kJ/mol	47.0333 ± 0.0010	2143-58-0*0
16.3	Methylperoxy anion	[CH3OO]- (g)	-89.68	-99.83	± 0.45	kJ/mol	47.0339 ± 0.0010	35683-44-4*0
9.9	Methyl hydroperoxide	CH3OOH (g)	-114.85	-127.67	± 0.43	kJ/mol	48.0413 ± 0.0010	3031-73-0*0
6.7	Hydroxymethyleneoxonium	[CH2OOH]+ (g)	792.94	782.80	± 0.63	kJ/mol	47.0328 ± 0.0010	77144-12-8*0
5.8	Ethylperoxy	CH3CH2OO (g)	-6.23	-22.20	± 0.64	kJ/mol	61.0599 ± 0.0017	3170-61-4*0
5.8	Ethylperoxy	CH3CH2OO (g, gauche)	-6.23	-22.26	± 0.64	kJ/mol	61.0599 ± 0.0017	3170-61-4*3
5.1	Ethaneperoxolate	[CH3CH2OO]- (g, gauche)	-120.47	-137.09	± 0.72	kJ/mol	61.0604 ± 0.0017	268728-75-2*3
5.1	Ethaneperoxolate	[CH3CH2OO]- (g)	-120.47	-136.53	± 0.72	kJ/mol	61.0604 ± 0.0017	268728-75-2*0
4.9	Carbon	C (g)	711.400	716.885	± 0.040	kJ/mol	12.01070 ± 0.00080	7440-44-0*0
4.9	Carbon	C (g, triplet)	711.400	716.885	± 0.040	kJ/mol	12.01070 ± 0.00080	7440-44-0*1

Most Influential reactions involving [CH3OO]+ (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
0.465	4566.13	CH3OO (g) → [CH3OO]+ (g)	Δ_rH°(0 K) = 10.259 ± 0.010 eV	Welch 2019, Welch 2018
0.444	4568.9	[CH3OO]+ (g) → C (g) + 3 H (g) + 2 O (g)	Δ_rH°(0 K) = 840.85 ± 1. kJ/mol	Welch 2019, Welch 2018
0.029	4566.11	CH3OO (g) → [CH3OO]+ (g)	Δ_rH°(0 K) = 10.274 ± 0.040 eV	Ruscic W1RO
0.023	4566.1	CH3OO (g) → [CH3OO]+ (g)	Δ_rH°(0 K) = 10.215 ± 0.015 (×2.954) eV	Tang 2020a
0.018	4566.2	CH3OO (g) → [CH3OO]+ (g)	Δ_rH°(0 K) = 10.265 ± 0.050 eV	Voronova 2018, Tang 2020a, est unc
0.011	4568.8	[CH3OO]+ (g) → C (g) + 3 H (g) + 2 O (g)	Δ_rH°(0 K) = 200.52 ± 1.50 kcal/mol	Ruscic W1RO
0.009	4568.4	[CH3OO]+ (g) → C (g) + 3 H (g) + 2 O (g)	Δ_rH°(0 K) = 201.00 ± 1.60 kcal/mol	Ruscic G4
0.008	4566.3	CH3OO (g) → [CH3OO]+ (g)	Δ_rH°(0 K) = 10.33 ± 0.05 (×1.445) eV	Meloni 2006
0.008	4566.7	CH3OO (g) → [CH3OO]+ (g)	Δ_rH°(0 K) = 10.280 ± 0.073 eV	Ruscic G4
0.008	4568.3	[CH3OO]+ (g) → C (g) + 3 H (g) + 2 O (g)	Δ_rH°(0 K) = 200.96 ± 1.72 kcal/mol	Ruscic G3X
0.008	4566.12	CH3OO (g) → [CH3OO]+ (g)	Δ_rH°(0 K) = 10.26 ± 0.075 eV	Meloni 2006, est unc
0.008	4566.10	CH3OO (g) → [CH3OO]+ (g)	Δ_rH°(0 K) = 10.213 ± 0.075 eV	Ruscic CBS-n, Meloni 2006
0.005	4568.6	[CH3OO]+ (g) → C (g) + 3 H (g) + 2 O (g)	Δ_rH°(0 K) = 201.74 ± 2.16 kcal/mol	Ruscic CBS-n
0.005	4566.6	CH3OO (g) → [CH3OO]+ (g)	Δ_rH°(0 K) = 10.263 ± 0.093 eV	Ruscic G3X
0.005	4568.7	[CH3OO]+ (g) → C (g) + 3 H (g) + 2 O (g)	Δ_rH°(0 K) = 203.20 ± 1.60 (×1.414) kcal/mol	Ruscic CBS-n
0.004	4566.9	CH3OO (g) → [CH3OO]+ (g)	Δ_rH°(0 K) = 10.285 ± 0.099 eV	Ruscic CBS-n

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. 1.156 of the Thermochemical Network (2024); available at ATcT.anl.gov
4		N. A. Seifert, B. Ruscic, R. Sivaramakrishnan, and K. Prozument, The C2H4O Isomers in the Oxidation of Ethylene J. Mol. Spectrosc. 398, 111847/1-8 (2023) [DOI: 10.1016/j.jms.2023.111847]
5		U. Jacovella, B. Ruscic, N. L. Chen, H.-L. Le, S. Boyé-Péronne, S. Hartweg, M. Roy-Chowdhury, G. A. Garcia, J.-C. Loison, and B. Gans, Refining Thermochemical Properties of CF, SiF, and Their Cations by Combining Photoelectron Spectroscopy, Quantum Chemical Calculations, and the Active Thermochemical Tables Approach Phys. Chem. Chem. Phys. 25, 30838-30847 (2023) [DOI: 10.1039/D3CP04244H]
6		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]
7		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] and Ruscic and Bross[7]).
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.