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].

Hydrogen iodide

Formula: HI (g)

CAS RN: 10034-85-2

ATcT ID: 10034-85-2*0

SMILES: I

InChI: InChI=1S/HI/h1H

InChIKey: XMBWDFGMSWQBCA-UHFFFAOYSA-N

Hills Formula: H1I1

2D Image:

Aliases: HI; Hydrogen iodide; Hydrogen monoiodide; Hydroiodic acid; Hydriodic acid; Iodhydric acid; Iodohydric acid; Iodohydrogen; Iodic acid; Iodine hydride; Iodine monohydride; UN 1787; UN 2197

Relative Molecular Mass: 127.912410 ± 0.000076

Δ_fH°(0 K)	Δ_fH°(298.15 K)	Uncertainty	Units
28.643	26.467	± 0.036	kJ/mol

3D Image of HI (g)

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Top contributors to the provenance of Δ_fH° of HI (g)

The 3 contributors listed below account for 95.7% of the provenance of Δ_fH° of HI (g).

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
78.4	1281.1	2 HI (g) → H2 (g) + I2 (g)	Δ_rG°(721.5 K) = 23.625 ± 0.080 kJ/mol	Taylor 1941, 3rd Law
10.9	1282.1	HI (g) → 1/2 H2 (g) + 1/2 I2 (g)	Δ_rG°(704 K) = 11.571 ± 0.028 (×3.83) kJ/mol	Rittenberg 1934, note HI, 3rd Law
6.3	1281.2	2 HI (g) → H2 (g) + I2 (g)	Δ_rH°(721.5 K) = 12.583 ± 0.282 kJ/mol	Taylor 1941, 2nd Law

Top 10 species with enthalpies of formation correlated to the Δ_fH° of HI (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	Δ_fH°(298.15 K)	Uncertainty	Units	Relative Molecular Mass	ATcT ID
39.3	Hydrogen iodide	HI (aq, 5130 H2O)	-56.648	± 0.089	kJ/mol	127.912410 ± 0.000076	10034-85-2*958
39.3	Hydrogen iodide	HI (aq, 5000 H2O)	-56.646	± 0.090	kJ/mol	127.912410 ± 0.000076	10034-85-2*844
39.2	Hydrogen iodide	HI (aq, 555.1 H2O)	-56.382	± 0.090	kJ/mol	127.912410 ± 0.000076	10034-85-2*895
39.2	Hydrogen iodide	HI (aq, 20000 H2O)	-56.734	± 0.090	kJ/mol	127.912410 ± 0.000076	10034-85-2*852
39.2	Hydrogen iodide	HI (aq, 10000 H2O)	-56.696	± 0.090	kJ/mol	127.912410 ± 0.000076	10034-85-2*850
39.2	Hydrogen iodide	HI (aq, 1500 H2O)	-56.525	± 0.090	kJ/mol	127.912410 ± 0.000076	10034-85-2*840
39.2	Hydrogen iodide	HI (aq, 50000 H2O)	-56.767	± 0.090	kJ/mol	127.912410 ± 0.000076	10034-85-2*855
39.2	Hydrogen iodide	HI (aq, 1250 H2O)	-56.499	± 0.090	kJ/mol	127.912410 ± 0.000076	10034-85-2*954
39.2	Hydrogen iodide	HI (aq, 700 H2O)	-56.416	± 0.090	kJ/mol	127.912410 ± 0.000076	10034-85-2*835
39.1	Hydrogen iodide	HI (aq, 1000 H2O)	-56.470	± 0.090	kJ/mol	127.912410 ± 0.000076	10034-85-2*839

Most Influential reactions involving HI (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
0.961	1288.1	HI (g) → HI (aq, 5130 H2O)	Δ_rH°(298.15 K) = -19.862 ± 0.020 kcal/mol	Vanderzee 1974
0.787	1281.1	2 HI (g) → H2 (g) + I2 (g)	Δ_rG°(721.5 K) = 23.625 ± 0.080 kJ/mol	Taylor 1941, 3rd Law
0.209	5907.4	CI4 (g) + 4 H2 (g) → CH4 (g) + 4 HI (g)	Δ_rH°(0 K) = -65.35 ± 1.0 kcal/mol	xyx 2016
0.132	6007.1	CHF3 (g) + I2 (g) → CF3I (g) + HI (g)	Δ_rH°(298.15 K) = 17.10 ± 0.34 kcal/mol	Goy 1967, as quoted by Cox 1970
0.109	1282.1	HI (g) → 1/2 H2 (g) + 1/2 I2 (g)	Δ_rG°(704 K) = 11.571 ± 0.028 (×3.83) kJ/mol	Rittenberg 1934, note HI, 3rd Law
0.063	1281.2	2 HI (g) → H2 (g) + I2 (g)	Δ_rH°(721.5 K) = 12.583 ± 0.282 kJ/mol	Taylor 1941, 2nd Law
0.061	5971.4	CH3I (g) + HI (g) → I2 (g) + CH4 (g)	Δ_rG°(669 K) = -10.34 ± 0.09 (×1.834) kcal/mol	Goy 1965, 3rd Law
0.057	5971.2	CH3I (g) + HI (g) → I2 (g) + CH4 (g)	Δ_rG°(630.5 K) = -10.48 ± 0.08 (×2.134) kcal/mol	Golden 1965, 3rd Law, Cox 1970
0.055	1374.2	HOI (g) + H2 (g) → H2O (g) + HI (g)	Δ_rH°(0 K) = -37.92 ± 3.1 kcal/mol	Ruscic unpub
0.052	1374.3	HOI (g) + H2 (g) → H2O (g) + HI (g)	Δ_rH°(0 K) = -37.80 ± 3.2 kcal/mol	Ruscic unpub
0.046	1374.1	HOI (g) + H2 (g) → H2O (g) + HI (g)	Δ_rH°(0 K) = -36.97 ± 3.4 kcal/mol	Ruscic unpub
0.037	3179.4	CH3CHCH2 (g) + 2 HI (g) → CH3CH2CH3 (g) + I2 (g)	Δ_rG°(597 K) = -5.79 ± 0.20 kcal/mol	Nangia 1964, Nangia 1964a, 3rd Law, est unc
0.027	1287.2	HI (g) → HI (aq)	Δ_rG°(298.15 K) = -53.93 ± 0.50 kJ/mol	Bates 1919, as quoted by CODATA Key Vals
0.022	1284.1	HI (g) + Br (g) → HBr (g) + I (g)	Δ_rH°(0 K) = -16.14 ± 0.2 kcal/mol	Feller 2008
0.018	2839.2	ICN (g) + HBr (g) → BrCN (g) + HI (g)	Δ_rH°(0 K) = 5.21 ± 3.1 kcal/mol	Ruscic unpub
0.016	2839.3	ICN (g) + HBr (g) → BrCN (g) + HI (g)	Δ_rH°(0 K) = 5.20 ± 3.2 kcal/mol	Ruscic unpub
0.015	2836.2	ICN (g) + H2 (g) → HCN (g) + HI (g)	Δ_rH°(0 K) = -15.93 ± 3.1 kcal/mol	Ruscic unpub
0.015	2839.1	ICN (g) + HBr (g) → BrCN (g) + HI (g)	Δ_rH°(0 K) = 5.31 ± 3.4 kcal/mol	Ruscic unpub
0.014	2836.3	ICN (g) + H2 (g) → HCN (g) + HI (g)	Δ_rH°(0 K) = -15.84 ± 3.2 kcal/mol	Ruscic unpub
0.012	2836.1	ICN (g) + H2 (g) → HCN (g) + HI (g)	Δ_rH°(0 K) = -14.57 ± 3.4 kcal/mol	Ruscic unpub

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.