Selected ATcT [1, 2] enthalpy of formation based on version 1.130 of the Thermochemical Network [3]

This version of ATcT results[4] was generated by additional expansion of version 1.128 [5,6] to include with the calculations provided in reference [4].

Dihydrogen cation

Formula: [H2]+ (g, para)

CAS RN: 12184-90-6

ATcT ID: 12184-90-6*2

SMILES: [H][H+]

InChI: InChI=1S/H2/h1H/q+1

InChIKey: ZZIJOQHRUPVPQC-UHFFFAOYSA-N

Hills Formula: H2+

2D Image:

Aliases: [H2]+; Dihydrogen cation; Dihydrogen ion (1+); Hydrogen molecule cation; Hydrogen molecular ion (1+); Hydrogen cation; Hydrogen ion (1+); Molecular hydrogen cation; Molecular hydrogen ion (1+); Diatomic hydrogen cation; Diatomic hydrogen ion (1+)

Relative Molecular Mass: 2.01533 ± 0.00014

Δ_fH°(0 K)	Δ_fH°(298.15 K)	Uncertainty	Units
1488.364	1488.480	± 0.000	kJ/mol

3D Image of [H2]+ (g, para)

spin ON spin OFF

Top contributors to the provenance of Δ_fH° of [H2]+ (g, para)

The 7 contributors listed below account for 91.8% of the provenance of Δ_fH° of [H2]+ (g, para).

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
26.2	65.1	H2 (g, para) → H2 (g)	Δ_rH°(0 K) = 0.0 ± 0.0 cm-1	triv
22.8	71.1	[H2]+ (g, para) → [H2]+ (g)	Δ_rH°(0 K) = 0. ± 0. cm-1	Moss 1993b
17.1	63.13	H2 (g) → [H2]+ (g)	Δ_rH°(0 K) = 124417.49113 ± 0.00074 cm-1	Liu 2012, note unc
14.4	69.1	H2 (g, para) → [H2]+ (g, para)	Δ_rH°(0 K) = 124417.491098 ± 0.000062 cm-1	Beyer 2019, note unc
6.8	72.1	[H2]+ (g, para) → [H2]+ (g, ortho)	Δ_rH°(0 K) = 58.2336750974 ± 0.0000000016 cm-1	Korobov 2018, note unc, Schuder 2017
2.1	76.2	H (g) → H+ (g)	Δ_rH°(0 K) = 109678.7717426 ± 0.0000020 cm-1	Liu 2009, note unc
2.1	76.1	H (g) → H+ (g)	Δ_rH°(0 K) = 109678.77174307 ± 0.00000020 cm-1	Mohr 2016, Sprecher 2010, note unc, Tiesinga 2021

Top 10 species with enthalpies of formation correlated to the Δ_fH° of [H2]+ (g, para)

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
68.5	Dihydrogen cation	[H2]+ (g, ortho)	1489.060	1488.480	± 0.000	kJ/mol	2.01533 ± 0.00014	12184-90-6*1
67.3	Dihydrogen	H2 (g, ortho)	1.417	0.019	± 0.000	kJ/mol	2.01588 ± 0.00014	1333-74-0*1
66.7	Dihydrogen	H2 (g, para)	-0.000	-0.058	± 0.000	kJ/mol	2.01588 ± 0.00014	1333-74-0*2
59.2	Dihydrogen cation	[H2]+ (g)	1488.364	1488.480	± 0.000	kJ/mol	2.01533 ± 0.00014	12184-90-6*0
45.9	Hydron	H+ (g)	1528.084	1530.047	± 0.000	kJ/mol	1.007391 ± 0.000070	12408-02-5*0
13.3	Deuterium hydride cation	[HD]+ (g)	1490.498	1490.587	± 0.000	kJ/mol	3.021493 ± 0.000070	12181-16-7*0
13.1	Hydrogen atom	H (g)	216.034	217.998	± 0.000	kJ/mol	1.007940 ± 0.000070	12385-13-6*0
9.8	Deuterium hydride	HD (g)	0.328	0.319	± 0.000	kJ/mol	3.022042 ± 0.000070	13983-20-5*0
3.8	Hydride	H- (g)	143.264	145.228	± 0.000	kJ/mol	1.008489 ± 0.000070	12184-88-2*0
-1.0	Deuterium atom cation	D+ (g)	1532.210	1534.123	± 0.000	kJ/mol	2.01355319809 ± 0.00000000040	14464-47-2*0

Most Influential reactions involving [H2]+ (g, para)

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
0.546	71.1	[H2]+ (g, para) → [H2]+ (g)	Δ_rH°(0 K) = 0. ± 0. cm-1	Moss 1993b
0.518	72.1	[H2]+ (g, para) → [H2]+ (g, ortho)	Δ_rH°(0 K) = 58.2336750974 ± 0.0000000016 cm-1	Korobov 2018, note unc, Schuder 2017
0.470	69.1	H2 (g, para) → [H2]+ (g, para)	Δ_rH°(0 K) = 124417.491098 ± 0.000062 cm-1	Beyer 2019, note unc
0.000	72.4	[H2]+ (g, para) → [H2]+ (g, ortho)	Δ_rH°(0 K) = 58.2032955 ± 0.0000002 (×30.64) cm-1	Karr 2008, Korobov 2006, Korobov 2006a, Korobov 2008, Liu 2009
0.000	72.2	[H2]+ (g, para) → [H2]+ (g, ortho)	Δ_rH°(0 K) = 58.2337 ± 0.05 cm-1	Moss 1993b, est unc
0.000	72.3	[H2]+ (g, para) → [H2]+ (g, ortho)	Δ_rH°(0 K) = 58.8 ± 0.2 (×2.89) cm-1	Herzberg 1972

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. 1.130 of the Thermochemical Network. Argonne National Laboratory, Lemont, Illinois 2023; available at ATcT.anl.gov [DOI: 10.17038/CSE/1997229]
4		N. Genossar, P. B. Changala, B. Gans, J.-C. Loison, S. Hartweg, M.-A. Martin-Drumel, G. A. Garcia, J. F. Stanton, B. Ruscic, and J. H. Baraban Ring-Opening Dynamics of the Cyclopropyl Radical and Cation: the Transition State Nature of the Cyclopropyl Cation J. Am. Chem. Soc. 144, 18518-18525 (2022) [DOI: 10.1021/jacs.2c07740]
5		B. Ruscic and D. H. Bross Active Thermochemical Tables: The Thermophysical and Thermochemical Properties of Methyl, CH3, and Methylene, CH2, Corrected for Nonrigid Rotor and Anharmonic Oscillator Effects. Mol. Phys. e1969046 (2021) [DOI: 10.1080/00268976.2021.1969046]
6		J. H. Thorpe, J. L. Kilburn, D. Feller, P. B. Changala, D. H. Bross, B. Ruscic, and J. F. Stanton, Elaborated Thermochemical Treatment of HF, CO, N2, and H2O: Insight into HEAT and Its Extensions J. Chem. Phys. 155, 184109 (2021) [DOI: 10.1063/5.0069322]
7		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]
8		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]).
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.