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].

Tetraoxygen

Formula: O4 (g, D2h singlet)

CAS RN: 12596-83-7

ATcT ID: 12596-83-7*21

SMILES: O=O.O=O

InChI: InChI=1S/2O2/c2*1-2

InChIKey: HICSRTVVKUYTJL-UHFFFAOYSA-N

SMILES: O1OOO1

InChI: InChI=1S/O4/c1-2-4-3-1

InChIKey: DKKUETPCPYRXSW-UHFFFAOYSA-N

SMILES: [O]OO[O]

InChI: InChI=1S/O4/c1-3-4-2

InChIKey: LEFFQQRPFPRAAY-UHFFFAOYSA-N

SMILES: [O][O]([O])[O]

InChI: InChI=1S/O4/c1-4(2)3

InChIKey: WCRUJNKRRKYHPE-UHFFFAOYSA-N

Hills Formula: O4

2D Image:

Aliases: O4; Tetraoxygen; Oxygen tetramer; Tetraatomic oxygen; Molecular oxygen dimer; Oxygen tetraatomic molecule; OOOO; O(OOO); OO(O)O

Relative Molecular Mass: 63.9976 ± 0.0012

Δ_fH°(0 K)	Δ_fH°(298.15 K)	Uncertainty	Units
69.8	65.1	± 4.4	kJ/mol

3D Image of O4 (g, D2h singlet)

spin ON spin OFF

Top contributors to the provenance of Δ_fH° of O4 (g, D2h singlet)

The 20 contributors listed below account only for 86.5% of the provenance of Δ_fH° of O4 (g, D2h singlet).
A total of 24 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
10.4	8115.2	1/2 O2 (g) → 1/4 O4 (g, D2h singlet)	Δ_rH°(0 K) = 3.47 ± 0.80 kcal/mol	Ruscic G4
10.4	8115.4	1/2 O2 (g) → 1/4 O4 (g, D2h singlet)	Δ_rH°(0 K) = 4.87 ± 0.80 kcal/mol	Ruscic CBS-n
9.0	8115.1	1/2 O2 (g) → 1/4 O4 (g, D2h singlet)	Δ_rH°(0 K) = 3.83 ± 0.86 kcal/mol	Ruscic G3X
5.7	8115.3	1/2 O2 (g) → 1/4 O4 (g, D2h singlet)	Δ_rH°(0 K) = 3.95 ± 1.08 kcal/mol	Ruscic CBS-n
5.3	8121.5	1/4 O4 (g, D2h singlet) → 1/4 O4 (g, C2h triplet)	Δ_rH°(0 K) = 1.31 ± 0.75 (×1.022) kcal/mol	Ruscic W1RO
4.9	8121.4	1/4 O4 (g, D2h singlet) → 1/4 O4 (g, C2h triplet)	Δ_rH°(0 K) = 1.91 ± 0.80 kcal/mol	Ruscic CBS-n
4.9	8121.2	1/4 O4 (g, D2h singlet) → 1/4 O4 (g, C2h triplet)	Δ_rH°(0 K) = 2.66 ± 0.80 kcal/mol	Ruscic G4
4.8	8120.5	1/4 O4 (g, D2h singlet) → 1/4 O4 (g, C2h singlet)	Δ_rH°(0 K) = 4.32 ± 0.75 kcal/mol	Ruscic W1RO
4.3	8120.2	1/4 O4 (g, D2h singlet) → 1/4 O4 (g, C2h singlet)	Δ_rH°(0 K) = 4.44 ± 0.80 kcal/mol	Ruscic G4
4.3	8120.4	1/4 O4 (g, D2h singlet) → 1/4 O4 (g, C2h singlet)	Δ_rH°(0 K) = 4.74 ± 0.80 kcal/mol	Ruscic CBS-n
4.2	8121.1	1/4 O4 (g, D2h singlet) → 1/4 O4 (g, C2h triplet)	Δ_rH°(0 K) = 2.87 ± 0.86 kcal/mol	Ruscic G3X
3.7	8120.1	1/4 O4 (g, D2h singlet) → 1/4 O4 (g, C2h singlet)	Δ_rH°(0 K) = 4.06 ± 0.86 kcal/mol	Ruscic G3X
2.7	8121.3	1/4 O4 (g, D2h singlet) → 1/4 O4 (g, C2h triplet)	Δ_rH°(0 K) = 1.89 ± 1.08 kcal/mol	Ruscic CBS-n
2.3	8120.3	1/4 O4 (g, D2h singlet) → 1/4 O4 (g, C2h singlet)	Δ_rH°(0 K) = 5.07 ± 1.08 kcal/mol	Ruscic CBS-n
1.7	8126.5	O4 (g, C2h triplet) + O2 (g) → 2 OOO (g)	Δ_rH°(0 K) = 44.09 ± 2.4 kcal/mol	Ruscic W1RO
1.7	8115.5	1/2 O2 (g) → 1/4 O4 (g, D2h singlet)	Δ_rH°(0 K) = 6.11 ± 0.75 (×2.594) kcal/mol	Ruscic W1RO
1.5	8126.4	O4 (g, C2h triplet) + O2 (g) → 2 OOO (g)	Δ_rH°(0 K) = 45.51 ± 2.6 kcal/mol	Ruscic CBS-n
1.5	8126.2	O4 (g, C2h triplet) + O2 (g) → 2 OOO (g)	Δ_rH°(0 K) = 44.54 ± 2.6 kcal/mol	Ruscic G4
1.3	8126.1	O4 (g, C2h triplet) + O2 (g) → 2 OOO (g)	Δ_rH°(0 K) = 43.56 ± 2.8 kcal/mol	Ruscic G3X
1.2	8117.2	1/2 O2 (g) → 1/4 O4 (g, C2h singlet)	Δ_rH°(0 K) = 7.91 ± 0.80 (×1.022) kcal/mol	Ruscic G4

Top 10 species with enthalpies of formation correlated to the Δ_fH° of O4 (g, D2h singlet)

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
41.2	Tetraoxygen	O4 (g, C2h singlet)	145.8	142.2	± 3.8	kJ/mol	63.9976 ± 0.0012	12596-83-7*22
39.2	Tetraoxygen	O4 (g, C2h triplet)	104.4	102.4	± 3.5	kJ/mol	63.9976 ± 0.0012	12596-83-7*11
14.0	Tetraoxygen	O4 (g, D3h singlet)	465.6	459.6	± 4.2	kJ/mol	63.9976 ± 0.0012	12596-83-7*24
12.9	Tetraoxygen	O4 (g, D2d singlet)	399.0	393.4	± 3.9	kJ/mol	63.9976 ± 0.0012	12596-83-7*23

Most Influential reactions involving O4 (g, D2h singlet)

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
0.122	8120.5	1/4 O4 (g, D2h singlet) → 1/4 O4 (g, C2h singlet)	Δ_rH°(0 K) = 4.32 ± 0.75 kcal/mol	Ruscic W1RO
0.113	8121.5	1/4 O4 (g, D2h singlet) → 1/4 O4 (g, C2h triplet)	Δ_rH°(0 K) = 1.31 ± 0.75 (×1.022) kcal/mol	Ruscic W1RO
0.107	8120.4	1/4 O4 (g, D2h singlet) → 1/4 O4 (g, C2h singlet)	Δ_rH°(0 K) = 4.74 ± 0.80 kcal/mol	Ruscic CBS-n
0.107	8120.2	1/4 O4 (g, D2h singlet) → 1/4 O4 (g, C2h singlet)	Δ_rH°(0 K) = 4.44 ± 0.80 kcal/mol	Ruscic G4
0.104	8121.2	1/4 O4 (g, D2h singlet) → 1/4 O4 (g, C2h triplet)	Δ_rH°(0 K) = 2.66 ± 0.80 kcal/mol	Ruscic G4
0.104	8121.4	1/4 O4 (g, D2h singlet) → 1/4 O4 (g, C2h triplet)	Δ_rH°(0 K) = 1.91 ± 0.80 kcal/mol	Ruscic CBS-n
0.104	8115.4	1/2 O2 (g) → 1/4 O4 (g, D2h singlet)	Δ_rH°(0 K) = 4.87 ± 0.80 kcal/mol	Ruscic CBS-n
0.104	8115.2	1/2 O2 (g) → 1/4 O4 (g, D2h singlet)	Δ_rH°(0 K) = 3.47 ± 0.80 kcal/mol	Ruscic G4
0.093	8120.1	1/4 O4 (g, D2h singlet) → 1/4 O4 (g, C2h singlet)	Δ_rH°(0 K) = 4.06 ± 0.86 kcal/mol	Ruscic G3X
0.090	8121.1	1/4 O4 (g, D2h singlet) → 1/4 O4 (g, C2h triplet)	Δ_rH°(0 K) = 2.87 ± 0.86 kcal/mol	Ruscic G3X
0.090	8115.1	1/2 O2 (g) → 1/4 O4 (g, D2h singlet)	Δ_rH°(0 K) = 3.83 ± 0.86 kcal/mol	Ruscic G3X
0.059	8120.3	1/4 O4 (g, D2h singlet) → 1/4 O4 (g, C2h singlet)	Δ_rH°(0 K) = 5.07 ± 1.08 kcal/mol	Ruscic CBS-n
0.057	8121.3	1/4 O4 (g, D2h singlet) → 1/4 O4 (g, C2h triplet)	Δ_rH°(0 K) = 1.89 ± 1.08 kcal/mol	Ruscic CBS-n
0.057	8115.3	1/2 O2 (g) → 1/4 O4 (g, D2h singlet)	Δ_rH°(0 K) = 3.95 ± 1.08 kcal/mol	Ruscic CBS-n
0.017	8115.5	1/2 O2 (g) → 1/4 O4 (g, D2h singlet)	Δ_rH°(0 K) = 6.11 ± 0.75 (×2.594) kcal/mol	Ruscic W1RO

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.