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].

O--HH Complex

Formula: (H2)(O) (g, vdW Cinfv ?)

CAS RN: *7732-18-5

ATcT ID: *7732-18-5*101

SMILES: [H][H].[O]

InChI: InChI=1S/O.H2/h;1H

InChIKey: XPISLILTAJWNBP-UHFFFAOYSA-N

Hills Formula: H2O1

2D Image:

Aliases: (H2)(O); O--HH Complex; (O)(H2); HHO; OHH

Relative Molecular Mass: 18.01528 ± 0.00033

Δ_fH°(0 K)	Δ_fH°(298.15 K)	Uncertainty	Units
247.7	249.0	± 2.7	kJ/mol

3D Image of (H2)(O) (g, vdW Cinfv ?)

spin ON spin OFF

Top contributors to the provenance of Δ_fH° of (H2)(O) (g, vdW Cinfv ?)

The 5 contributors listed below account for 91.3% of the provenance of Δ_fH° of (H2)(O) (g, vdW Cinfv ?).

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
28.0	150.6	(H2)(O) (g, vdW Cinfv ?) → H2 (g) + O (g, triplet)	Δ_rH°(0 K) = -0.43 ± 1.2 kcal/mol	Ruscic ab initio
17.9	150.5	(H2)(O) (g, vdW Cinfv ?) → H2 (g) + O (g, triplet)	Δ_rH°(0 K) = -0.50 ± 1.50 kcal/mol	Ruscic W1RO
15.7	150.2	(H2)(O) (g, vdW Cinfv ?) → H2 (g) + O (g, triplet)	Δ_rH°(0 K) = 0.24 ± 1.60 kcal/mol	Ruscic G4
15.7	150.4	(H2)(O) (g, vdW Cinfv ?) → H2 (g) + O (g, triplet)	Δ_rH°(0 K) = -0.61 ± 1.60 kcal/mol	Ruscic CBS-n
13.6	150.1	(H2)(O) (g, vdW Cinfv ?) → H2 (g) + O (g, triplet)	Δ_rH°(0 K) = 1.26 ± 1.72 kcal/mol	Ruscic G3X

Most Influential reactions involving (H2)(O) (g, vdW Cinfv ?)

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
0.280	150.6	(H2)(O) (g, vdW Cinfv ?) → H2 (g) + O (g, triplet)	Δ_rH°(0 K) = -0.43 ± 1.2 kcal/mol	Ruscic ab initio
0.179	150.5	(H2)(O) (g, vdW Cinfv ?) → H2 (g) + O (g, triplet)	Δ_rH°(0 K) = -0.50 ± 1.50 kcal/mol	Ruscic W1RO
0.158	150.2	(H2)(O) (g, vdW Cinfv ?) → H2 (g) + O (g, triplet)	Δ_rH°(0 K) = 0.24 ± 1.60 kcal/mol	Ruscic G4
0.158	150.4	(H2)(O) (g, vdW Cinfv ?) → H2 (g) + O (g, triplet)	Δ_rH°(0 K) = -0.61 ± 1.60 kcal/mol	Ruscic CBS-n
0.136	150.1	(H2)(O) (g, vdW Cinfv ?) → H2 (g) + O (g, triplet)	Δ_rH°(0 K) = 1.26 ± 1.72 kcal/mol	Ruscic G3X
0.086	150.3	(H2)(O) (g, vdW Cinfv ?) → H2 (g) + O (g, triplet)	Δ_rH°(0 K) = -1.13 ± 2.16 kcal/mol	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. 1.172 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.