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].

Methylperoxy

Formula: CH3OO (g)
CAS RN: 2143-58-0
ATcT ID: 2143-58-0*0
SMILES: CO[O]
InChI: InChI=1S/CH3O2/c1-3-2/h1H3
InChIKey: WTFNSXYULBQCQV-UHFFFAOYSA-N
Hills Formula: C1H3O2

2D Image:

CO[O]
Aliases: CH3OO; Methylperoxy; Methyldioxidanyl; Methyldioxy; Methylperoxyl; Methylperoxo; Methyl peroxide radical; Methyl peroxy radical; Methyldioxy radical
Relative Molecular Mass: 47.0333 ± 0.0010

   ΔfH°(0 K)   ΔfH°(298.15 K)UncertaintyUnits
22.5213.07± 0.34kJ/mol

3D Image of CH3OO (g)

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Top contributors to the provenance of ΔfH° of CH3OO (g)

The 20 contributors listed below account only for 66.0% of the provenance of ΔfH° of CH3OO (g).
A total of 123 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
21.34578.6 CH3OO (g) → CH3 (g) O2 (g) ΔrH°(0 K) = 30.40 ± 0.17 kcal/molNguyen 2014a
10.94565.9 CH3OO (g) → C (g) + 3 H (g) + 2 O (g) ΔrH°(0 K) = 1830.74 ± 1. kJ/molWelch 2019, Welch 2018
6.74569.9 [CH3OO]- (g) → C (g) + 3 H (g) + 2 O (g) ΔrH°(0 K) = 1942.76 ± 1. kJ/molWelch 2019, Welch 2018
3.34568.9 [CH3OO]+ (g) → C (g) + 3 H (g) + 2 O (g) ΔrH°(0 K) = 840.85 ± 1. kJ/molWelch 2019, Welch 2018
2.94576.1 CH3OO (g) → [CH3]+ (g) O2 (g) ΔrH°(0 K) = 11.15 ± 0.02 eVTang 2020a
2.64570.1 CH4 (g) + 2 H2O (g) → CH3OO (g) + 5/2 H2 (g) ΔrH°(0 K) = 567.06 ± 2.0 kJ/molKlippenstein 2017
2.44578.7 CH3OO (g) → CH3 (g) O2 (g) ΔrH°(0 K) = 30.75 ± 0.50 kcal/molNguyen 2014a, est unc
2.34566.13 CH3OO (g) → [CH3OO]+ (g) ΔrH°(0 K) = 10.259 ± 0.010 eVWelch 2019, Welch 2018
2.14567.1 [CH3OO]- (g) → CH3OO (g) ΔrH°(0 K) = 1.161 ± 0.005 eVBlanksby 2001
2.14476.9 CH3OOH (g) → C (g) + 4 H (g) + 2 O (g) ΔrH°(0 K) = 2184.34 ± 1. kJ/molWelch 2019, Welch 2018
1.24576.2 CH3OO (g) → [CH3]+ (g) O2 (g) ΔrH°(0 K) = 11.164 ± 0.030 eVVoronova 2018, Tang 2020a, est unc
1.13166.6 HC(O)OO (g, syn) CH4 (g) → CH3OO (g) CH2O (g) ΔrH°(0 K) = 83.83 ± 2.0 kJ/molKlippenstein 2017
1.04623.6 CH3CH2OO (g, gauche) CH3 (g) → CH3OO (g) CH3CH2 (g) ΔrH°(0 K) = 10.09 ± 2.00 kJ/molKlippenstein 2017
0.84574.6 CH3OO (g) HOO (g) → CH3OOH (g) O2 (g, triplet) ΔrH°(0 K) = -152.74 ± 2.0 kJ/molKlippenstein 2017
0.84571.10 CH3OOH (g) → CH3OO (g) H (g) ΔrH°(0 K) = 353.47 ± 2.0 kJ/molKlippenstein 2017
0.84571.9 CH3OOH (g) → CH3OO (g) H (g) ΔrH°(0 K) = 353.60 ± 2. kJ/molWelch 2019, Welch 2018
0.84572.9 CH3OO (g) HOOH (g) → CH3OOH (g) HOO (g) ΔrH°(0 K) = 6.76 ± 2.0 kJ/molKlippenstein 2017
0.84574.1 CH3OO (g) HOO (g) → CH3OOH (g) O2 (g, triplet) ΔrH°(0 K) = -36.14 ± 0.5 kcal/molNguyen 2022
0.64579.8 CH3OO (g) NO (g) → CH3O (g) ONO (g) ΔrH°(0 K) = -11.77 ± 0.9 kcal/molRuscic W1RO
0.54577.6 CH3OO (g) → CH3 (g) O2 (g) ΔrG°(752.6 K) = 38.10 ± 1.90 (×2.278) kJ/molKnyazev 1998, Knyazev 1998, 3rd Law

Top 10 species with enthalpies of formation correlated to the ΔfH° 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 Image    ΔfH°(0 K)    ΔfH°(298.15 K) Uncertainty Units Relative
Molecular
Mass
ATcT ID
58.6 Methylperoxy anion[CH3OO]- (g)CO[O-]-89.68-99.83± 0.45kJ/mol47.0339 ±
0.0010
35683-44-4*0
35.1 Methyl hydroperoxideCH3OOH (g)COO-114.85-127.67± 0.43kJ/mol48.0413 ±
0.0010
3031-73-0*0
27.7 Methoxyoxoniumylidene[CH3OO]+ (g)CO[O+]1012.321003.49± 0.67kJ/mol47.0328 ±
0.0010
86475-50-5*0
23.9 Hydroxymethyleneoxonium[CH2OOH]+ (g)C=[O+]O792.94782.80± 0.63kJ/mol47.0328 ±
0.0010
77144-12-8*0
20.5 EthylperoxyCH3CH2OO (g)CCO[O]-6.23-22.20± 0.64kJ/mol61.0599 ±
0.0017
3170-61-4*0
20.5 EthylperoxyCH3CH2OO (g, gauche)CCO[O]-6.23-22.26± 0.64kJ/mol61.0599 ±
0.0017
3170-61-4*3
18.0 Ethaneperoxolate[CH3CH2OO]- (g, gauche)CCO[O-]-120.47-137.09± 0.72kJ/mol61.0604 ±
0.0017
268728-75-2*3
18.0 Ethaneperoxolate[CH3CH2OO]- (g)CCO[O-]-120.47-136.53± 0.72kJ/mol61.0604 ±
0.0017
268728-75-2*0
17.5 HydroperoxymethylCH2OOH (g)[CH2]OO73.2465.94± 0.97kJ/mol47.0333 ±
0.0010
74087-87-9*0
16.8 PeroxyformylHC(O)OO (g, syn)C(=O)O[O]-100.42-105.73± 0.67kJ/mol61.0168 ±
0.0012
56240-83-6*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
0.5894567.1 [CH3OO]- (g) → CH3OO (g) ΔrH°(0 K) = 1.161 ± 0.005 eVBlanksby 2001
0.4654566.13 CH3OO (g) → [CH3OO]+ (g) ΔrH°(0 K) = 10.259 ± 0.010 eVWelch 2019, Welch 2018
0.2184578.6 CH3OO (g) → CH3 (g) O2 (g) ΔrH°(0 K) = 30.40 ± 0.17 kcal/molNguyen 2014a
0.1768249.5 C6H5OOH (g) CH3OO (g) → C6H5OO (g) CH3OOH (g) ΔrH°(0 K) = 0.83 ± 0.85 kcal/molRuscic W1RO
0.1578249.1 C6H5OOH (g) CH3OO (g) → C6H5OO (g) CH3OOH (g) ΔrH°(0 K) = 1.15 ± 0.90 kcal/molRuscic G3X
0.1578249.2 C6H5OOH (g) CH3OO (g) → C6H5OO (g) CH3OOH (g) ΔrH°(0 K) = -0.09 ± 0.90 kcal/molRuscic G4
0.1578249.4 C6H5OOH (g) CH3OO (g) → C6H5OO (g) CH3OOH (g) ΔrH°(0 K) = 0.51 ± 0.90 kcal/molRuscic CBS-n
0.1504618.6 CH3CH2OO (g, gauche) CH3OOH (g) → CH3CH2OOH (g) CH3OO (g) ΔrH°(0 K) = 0.81 ± 1.50 kJ/molWelch 2019, Welch 2018
0.1474567.10 [CH3OO]- (g) → CH3OO (g) ΔrH°(0 K) = 1.161 ± 0.010 eVWelch 2019, Welch 2018
0.1278249.3 C6H5OOH (g) CH3OO (g) → C6H5OO (g) CH3OOH (g) ΔrH°(0 K) = 1.17 ± 1.0 kcal/molRuscic CBS-n
0.1203166.6 HC(O)OO (g, syn) CH4 (g) → CH3OO (g) CH2O (g) ΔrH°(0 K) = 83.83 ± 2.0 kJ/molKlippenstein 2017
0.1144645.5 CH3CHOOH (g) CH3OO (g) → CH3CH2OO (g, gauche) CH2OOH (g) ΔrH°(0 K) = 1.10 ± 0.85 kcal/molRuscic W1RO
0.1104565.9 CH3OO (g) → C (g) + 3 H (g) + 2 O (g) ΔrH°(0 K) = 1830.74 ± 1. kJ/molWelch 2019, Welch 2018
0.1078246.2 C6H5OO (g) CH3 (g) → C6H5 (g) CH3OO (g) ΔrH°(0 K) = 16.66 ± 1.0 kcal/molRuscic G4
0.1054623.6 CH3CH2OO (g, gauche) CH3 (g) → CH3OO (g) CH3CH2 (g) ΔrH°(0 K) = 10.09 ± 2.00 kJ/molKlippenstein 2017
0.1024645.1 CH3CHOOH (g) CH3OO (g) → CH3CH2OO (g, gauche) CH2OOH (g) ΔrH°(0 K) = 1.14 ± 0.90 kcal/molRuscic G3X
0.1024645.2 CH3CHOOH (g) CH3OO (g) → CH3CH2OO (g, gauche) CH2OOH (g) ΔrH°(0 K) = 1.28 ± 0.90 kcal/molRuscic G4
0.1024645.4 CH3CHOOH (g) CH3OO (g) → CH3CH2OO (g, gauche) CH2OOH (g) ΔrH°(0 K) = 1.34 ± 0.90 kcal/molRuscic CBS-n
0.0988244.5 C6H5OO (g) CH3O (g) → C6H5O (g) CH3OO (g) ΔrH°(0 K) = -21.48 ± 0.9 kcal/molRuscic W1RO
0.0898246.1 C6H5OO (g) CH3 (g) → C6H5 (g) CH3OO (g) ΔrH°(0 K) = 17.83 ± 1.1 kcal/molRuscic G3X


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. 1.156 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.