Selected ATcT [1, 2] enthalpy of formation based on version 1.122 of the Thermochemical Network [3]

This version of ATcT results was partially described in Ruscic et al. [4], and was also used for the initial development of high-accuracy ANLn composite electronic structure methods [5].

Species Name Formula Image    ΔfH°(0 K)    ΔfH°(298.15 K) Uncertainty Units Relative
Molecular
Mass		 ATcT ID
DioxidanylHO2 (g)O[O]15.1612.26± 0.16kJ/mol33.00674 ±
0.00060		3170-83-0*0

Representative Geometry of HO2 (g)

spin ON           spin OFF
          

Top contributors to the provenance of ΔfH° of HO2 (g)

The 20 contributors listed below account only for 74.7% of the provenance of ΔfH° of HO2 (g).
A total of 52 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
7.5263.4 HO2 (g) → H (g) + 2 O (g) ΔrH°(0 K) = 694.85 ± 0.56 kJ/molHarding 2008
6.0270.5 HO2 (g) → H (g) + O2 (g) ΔrH°(0 K) = 48.02 ± 0.15 kcal/molFlowers 2004, est unc
6.0261.8 HO2 (g) → H (g) + 2 O (g) ΔrH°(0 K) = 166.00 ± 0.15 kcal/molFlowers 2004, est unc
5.8272.1 OH (g) + O2 (g) → HO2 (g) + O (g) ΔrH°(0 K) = 53.81 ± 0.15 kcal/molFlowers 2004, est unc
5.8271.4 HO2 (g) → OH (g) + O (g) ΔrH°(0 K) = 64.16 ± 0.15 kcal/molFlowers 2004, est unc
4.8263.2 HO2 (g) → H (g) + 2 O (g) ΔrH°(0 K) = 695.10 ± 0.70 kJ/molHarding 2008
4.8264.1 HO2 (g) → [HO2]+ (g) ΔrH°(0 K) = 11.352 ± 0.007 eVLitorja 1998a
4.3263.3 HO2 (g) → H (g) + 2 O (g) ΔrH°(0 K) = 694.64 ± 0.74 kJ/molHarding 2008
4.2263.1 HO2 (g) → H (g) + 2 O (g) ΔrH°(0 K) = 694.56 ± 0.75 kJ/molTajti 2004, est unc
3.9273.4 H2O2 (g) → H (g) + HO2 (g) ΔrH°(0 K) = 360.25 ± 0.75 kJ/molTajti 2004, est unc
3.3263.5 HO2 (g) → H (g) + 2 O (g) ΔrH°(0 K) = 694.99 ± 0.84 kJ/molHarding 2008
3.3263.7 HO2 (g) → H (g) + 2 O (g) ΔrH°(0 K) = 694.73 ± 0.84 kJ/molHarding 2008
2.3264.2 HO2 (g) → [HO2]+ (g) ΔrH°(0 K) = 11.35 ± 0.01 eVDyke 1981
2.3284.2 Cl (g) + HO2 (g) → OH (g) + ClO (g) ΔrG°(293 K) = 1.3 ± 1.0 kJ/molHills 1984, note HO2
1.9283.2 HO2 (g) + NO (g) → OH (g) + ONO (g) ΔrH°(676 K) = -29.9 ± 1.1 kJ/molHoward 1980, 2nd Law
1.8263.6 HO2 (g) → H (g) + 2 O (g) ΔrH°(0 K) = 694.53 ± 1.14 kJ/molHarding 2008
1.5262.5 HO2 (g) → H (g) + 2 O (g) ΔrH°(0 K) = 165.97 ± 0.30 kcal/molMartin 2006, Karton 2009c, Karton 2011
1.5262.6 HO2 (g) → H (g) + 2 O (g) ΔrH°(0 K) = 165.97 ± 0.30 kcal/molKarton 2008, Karton 2009c
1.5261.10 HO2 (g) → H (g) + 2 O (g) ΔrH°(0 K) = 166.0 ± 0.3 kcal/molFeller 2007, Feller 2006
1.4273.3 H2O2 (g) → H (g) + HO2 (g) ΔrH°(0 K) = 86.11 ± 0.30 kcal/molKarton 2008

Top 10 species with enthalpies of formation correlated to the ΔfH° of HO2 (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
34.1 Dioxidanide[HO2]- (g)O[O-]-88.86-91.52± 0.38kJ/mol33.00729 ±
0.00060		14691-59-9*0
14.1 Dioxygenyl fluorideFOO (g)FO[O]26.7525.04± 0.27kJ/mol50.99720 ±
0.00060		15499-23-7*0
13.4 Chlorine superoxideClOO (g)ClO[O]103.82102.73± 0.37kJ/mol67.4515 ±
0.0011		17376-09-9*0
13.3 Peroxyhypochlorite[ClOO]- (g)ClO[O-]-249.32-249.88± 0.37kJ/mol67.4520 ±
0.0011		224299-14-3*0
7.6 WaterH2O (g, ortho)O-238.646-241.834± 0.027kJ/mol18.01528 ±
0.00033		7732-18-5*1
7.6 WaterH2O (g, para)O-238.931-241.834± 0.027kJ/mol18.01528 ±
0.00033		7732-18-5*2
7.6 WaterH2O (g)O-238.931-241.834± 0.027kJ/mol18.01528 ±
0.00033		7732-18-5*0
7.6 Hydroxyde[OH]- (g)[OH-]-139.091-139.058± 0.027kJ/mol17.00789 ±
0.00031		14280-30-9*0
7.6 HydroxylOH (g)[OH]37.25037.490± 0.027kJ/mol17.00734 ±
0.00031		3352-57-6*0
7.6 WaterH2O (l, eq.press.)O-285.830± 0.027kJ/mol18.01528 ±
0.00033		7732-18-5*589

Most Influential reactions involving HO2 (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
0.380265.2 [HO2]- (g) → HO2 (g) ΔrH°(0 K) = 1.078 ± 0.006 eVRamond 2001, Clifford 1998
0.380265.1 [HO2]- (g) → HO2 (g) ΔrH°(0 K) = 1.078 ± 0.006 eVRamond 2002
0.091696.5 ClOO (g) + H (g) → HO2 (g) + Cl (g) ΔrH°(0 K) = -44.09 ± 0.30 kcal/molKarton 2009c
0.079531.7 FOO (g) + OH (g) → HO2 (g) + FO (g) ΔrH°(0 K) = 14.93 ± 0.25 kcal/molKarton 2009c
0.075263.4 HO2 (g) → H (g) + 2 O (g) ΔrH°(0 K) = 694.85 ± 0.56 kJ/molHarding 2008
0.072532.6 FOO (g) + H (g) → HO2 (g) + F (g) ΔrH°(0 K) = -35.82 ± 0.25 kcal/molKarton 2009c
0.071264.1 HO2 (g) → [HO2]+ (g) ΔrH°(0 K) = 11.352 ± 0.007 eVLitorja 1998a
0.064697.4 ClOO (g) + OH (g) → HO2 (g) + ClO (g) ΔrH°(0 K) = -5.57 ± 0.30 (×1.189) kcal/molKarton 2009c
0.060272.1 OH (g) + O2 (g) → HO2 (g) + O (g) ΔrH°(0 K) = 53.81 ± 0.15 kcal/molFlowers 2004, est unc
0.060271.4 HO2 (g) → OH (g) + O (g) ΔrH°(0 K) = 64.16 ± 0.15 kcal/molFlowers 2004, est unc
0.060270.5 HO2 (g) → H (g) + O2 (g) ΔrH°(0 K) = 48.02 ± 0.15 kcal/molFlowers 2004, est unc
0.060261.8 HO2 (g) → H (g) + 2 O (g) ΔrH°(0 K) = 166.00 ± 0.15 kcal/molFlowers 2004, est unc
0.0592909.1 O(CH2CH2) (g) + OH (g) → C2H4 (g) + HO2 (g) ΔrH°(0 K) = 18.99 ± 0.4 kcal/molWilke 2008, est unc
0.051697.3 ClOO (g) + OH (g) → HO2 (g) + ClO (g) ΔrH°(0 K) = -5.87 ± 0.40 kcal/molKarton 2009c
0.051696.4 ClOO (g) + H (g) → HO2 (g) + Cl (g) ΔrH°(0 K) = -44.59 ± 0.40 kcal/molKarton 2009c
0.048263.2 HO2 (g) → H (g) + 2 O (g) ΔrH°(0 K) = 695.10 ± 0.70 kJ/molHarding 2008
0.047265.3 [HO2]- (g) → HO2 (g) ΔrH°(0 K) = 1.078 ± 0.017 eVOakes 1985
0.046273.4 H2O2 (g) → H (g) + HO2 (g) ΔrH°(0 K) = 360.25 ± 0.75 kJ/molTajti 2004, est unc
0.0462953.8 CH3OO (g) + H2O2 (g) → CH3OOH (g) + HO2 (g) ΔrH°(0 K) = 1.48 ± 0.9 kcal/molRuscic W1RO
0.043263.3 HO2 (g) → H (g) + 2 O (g) ΔrH°(0 K) = 694.64 ± 0.74 kJ/molHarding 2008
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. 1.122 of the Thermochemical Network (2016); available at ATcT.anl.gov
4   B. Ruscic,
Active Thermochemical Tables: Sequential Bond Dissociation Enthalpies of Methane, Ethane, and Methanol and the Related Thermochemistry.
J. Phys. Chem. A 119, 7810-7837 (2015) [DOI: 10.1021/acs.jpca.5b01346]
5   S. J. Klippenstein, L. B. Harding, and B. Ruscic,
Ab initio Computations and Active Thermochemical Tables Hand in Hand: Heats of Formation of Core Combustion Species.
J. Phys. Chem. A 121, 6580-6602 (2017) [DOI: 10.1021/acs.jpca.7b05945]
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]
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]).
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.