Selected ATcT [1, 2] enthalpy of formation based on version 1.176 of the Thermochemical Network [3]

This version of ATcT results[3] was generated by additional expansion of version 1.172 to include species related to Criegee intermediates that are involved in several ongoing studies[4].

Hypobromous acid

Formula: HOBr (g)

CAS RN: 13517-11-8

ATcT ID: 13517-11-8*0

SMILES: OBr

InChI: InChI=1S/BrHO/c1-2/h2H

InChIKey: CUILPNURFADTPE-UHFFFAOYSA-N

Hills Formula: Br1H1O1

2D Image:

Aliases: Hypobromous acid; Hydrogen oxybromide; Bromine hydroxide; Hydroxyl bromide; Hydroxybromine; HOBr; BrOH

Relative Molecular Mass: 96.9113 ± 0.0010

Δ_fH°(0 K)	Δ_fH°(298.15 K)	Uncertainty	Units
-51.27	-61.75	± 0.48	kJ/mol

3D Image of HOBr (g)

spin ON spin OFF

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

The 20 contributors listed below account only for 86.2% of the provenance of Δ_fH° of HOBr (g).
A total of 27 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
20.1	1269.1	HOBr (g) + Cl (g) → BrCl (g) + OH (g)	Δ_rG°(298.15 K) = -10.14 ± 1.04 kJ/mol	Loewenstein 1984, Kukui 1996, Monks 1993a, Loewenstein 1984
19.5	1258.10	HOBr (g) + HCl (g) → HOCl (g) + HBr (g)	Δ_rH°(0 K) = 9.94 ± 0.25 kcal/mol	Trogolo 2015, est unc
10.1	1251.7	HOBr (g) → H (g) + O (g) + Br (g)	Δ_rH°(0 K) = 151.19 ± 0.35 kcal/mol	Trogolo 2015, est unc
10.1	1255.6	H2O (g) + Br (g) → HOBr (g) + H (g)	Δ_rH°(0 K) = 68.26 ± 0.35 kcal/mol	Trogolo 2015, est unc
3.5	1247.1	BrOBr (g) + H2O (g) → 2 HOBr (g)	Δ_rG°(298.15 K) = 9.70 ± 1.2 kJ/mol	Hassanzadeh 1997, Orlando 1995
3.4	1251.6	HOBr (g) → H (g) + O (g) + Br (g)	Δ_rH°(0 K) = 151.16 ± 0.60 kcal/mol	Denis 2006, est unc
2.8	1245.4	BrOBr (g) → 2 Br (g) + O (g)	Δ_rH°(0 K) = 85.54 ± 1.0 kcal/mol	Grant 2010
2.7	1227.3	BrO (g) → [BrO]+ (g)	Δ_rH°(0 K) = 241.1 ± 0.8 kcal/mol	Francisco 1998
1.8	1249.4	BrBrO (g) → 2 Br (g) + O (g)	Δ_rH°(0 K) = 71.36 ± 1.0 kcal/mol	Grant 2010
1.7	1259.1	HOBr (g) + HCl (g) → HOCl (g) + HBr (g)	Δ_rH°(298.15 K) = 10.81 ± 0.60 (×1.384) kcal/mol	Denis 2006, est unc
1.5	1267.1	HOBr (g) → Br+ (g) + OH (g)	Δ_rH°(0 K) = 13.915 ± 0.018 (×2.181) eV	Ruscic 1994a
1.2	1246.4	BrOBr (g) + OBrO (g) → 3 BrO (g)	Δ_rH°(0 K) = 25.16 ± 1.0 kcal/mol	Grant 2010
1.2	1268.1	HOBr (g) → Br (g) + OH (g)	Δ_rH°(0 K) = 17227 ± 350 cm-1	Lock 1996
1.0	1108.2	Br2 (cr,l) → Br2 (g)	Δ_rH°(298.15 K) = 7.386 ± 0.027 kcal/mol	Hildenbrand 1958
0.9	1263.4	HOBr (g) + [OH]- (g) → H2O (g) + [BrO]- (g)	Δ_rH°(0 K) = -33.62 ± 1.0 kcal/mol	Ruscic G4
0.9	1265.4	HOBr (g) + [ClO]- (g) → HOCl (g) + [BrO]- (g)	Δ_rH°(0 K) = -0.90 ± 1.0 kcal/mol	Ruscic G4
0.8	1248.1	BrOBr (g) → [BrO]+ (g) + Br (g)	Δ_rH°(0 K) = 11.778 ± 0.014 eV	Thorn 1996a, AE corr
0.8	1264.4	HOBr (g) + [FO]- (g) → HOF (g) + [BrO]- (g)	Δ_rH°(0 K) = -4.87 ± 1.0 kcal/mol	Ruscic G4
0.7	1257.4	HOBr (g) + HF (g) → HOF (g) + HBr (g)	Δ_rH°(0 K) = 51.68 ± 1.3 kcal/mol	Ruscic G4
0.6	1227.7	BrO (g) → [BrO]+ (g)	Δ_rH°(0 K) = 10.444 ± 0.073 eV	Ruscic G4

Top 10 species with enthalpies of formation correlated to the Δ_fH° of HOBr (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°(0 K)	Δ_fH°(298.15 K)	Uncertainty	Units	Relative Molecular Mass	ATcT ID
88.7	Hypobromous acid cation	[HOBr]+ (g)	975.25	964.63	± 0.54	kJ/mol	96.9108 ± 0.0010	154804-02-1*0
60.2	Bromo hypobromite	BrOBr (g)	121.1	104.6	± 1.2	kJ/mol	175.8074 ± 0.0020	21308-80-5*0
38.4	Oxobromonium	[BrO]+ (g)	1140.0	1132.2	± 1.6	kJ/mol	95.9029 ± 0.0010	142315-39-7*0
28.1	Bromosyl bromide	BrBrO (g)	180.4	164.6	± 2.1	kJ/mol	175.8074 ± 0.0020	68322-97-4*0
13.1	Hypobromite	[BrO]- (g)	-95.99	-103.47	± 0.53	kJ/mol	95.9039 ± 0.0010	14380-62-2*0
10.8	Dibromine	Br2 (g)	45.70	30.90	± 0.11	kJ/mol	159.8080 ± 0.0020	7726-95-6*0
10.8	Bromine atom	Br (g, 2P1/2)	162.010	155.947	± 0.055	kJ/mol	79.90400 ± 0.00100	10097-32-2*2
10.8	Bromine atom	Br (g, 2P3/2)	117.925	111.863	± 0.055	kJ/mol	79.90400 ± 0.00100	10097-32-2*1
10.8	Bromine atom	Br (g)	117.925	111.863	± 0.055	kJ/mol	79.90400 ± 0.00100	10097-32-2*0
10.8	Bromide	Br- (g)	-206.612	-212.674	± 0.055	kJ/mol	79.90455 ± 0.00100	24959-67-9*0

Most Influential reactions involving HOBr (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
0.720	1252.2	HOBr (g) → [HOBr]+ (g)	Δ_rH°(0 K) = 10.638 ± 0.003 eV	Ruscic 1994a
0.668	1247.1	BrOBr (g) + H2O (g) → 2 HOBr (g)	Δ_rG°(298.15 K) = 9.70 ± 1.2 kJ/mol	Hassanzadeh 1997, Orlando 1995
0.259	1252.1	HOBr (g) → [HOBr]+ (g)	Δ_rH°(0 K) = 10.642 ± 0.005 eV	Ruscic 1994
0.207	1258.10	HOBr (g) + HCl (g) → HOCl (g) + HBr (g)	Δ_rH°(0 K) = 9.94 ± 0.25 kcal/mol	Trogolo 2015, est unc
0.204	1269.1	HOBr (g) + Cl (g) → BrCl (g) + OH (g)	Δ_rG°(298.15 K) = -10.14 ± 1.04 kJ/mol	Loewenstein 1984, Kukui 1996, Monks 1993a, Loewenstein 1984
0.103	1251.7	HOBr (g) → H (g) + O (g) + Br (g)	Δ_rH°(0 K) = 151.19 ± 0.35 kcal/mol	Trogolo 2015, est unc
0.103	1255.6	H2O (g) + Br (g) → HOBr (g) + H (g)	Δ_rH°(0 K) = 68.26 ± 0.35 kcal/mol	Trogolo 2015, est unc
0.063	2924.9	BrCN (g) + HOCl (g) → ClCN (g) + HOBr (g)	Δ_rH°(0 K) = -8.3 ± 1.0 (×1.354) kcal/mol	Lee 1995c
0.055	1247.3	BrOBr (g) + H2O (g) → 2 HOBr (g)	Δ_rH°(0 K) = 3.85 ± 1.0 kcal/mol	Ruscic G4
0.045	1247.2	BrOBr (g) + H2O (g) → 2 HOBr (g)	Δ_rH°(0 K) = 3.48 ± 1.1 kcal/mol	Ruscic G3X
0.037	1264.4	HOBr (g) + [FO]- (g) → HOF (g) + [BrO]- (g)	Δ_rH°(0 K) = -4.87 ± 1.0 kcal/mol	Ruscic G4
0.035	1251.6	HOBr (g) → H (g) + O (g) + Br (g)	Δ_rH°(0 K) = 151.16 ± 0.60 kcal/mol	Denis 2006, est unc
0.034	1402.1	HOI (g) + Br- (g) → HOBr (g) + I- (g)	Δ_rH°(0 K) = 22.6 ± 15 kJ/mol	Hassanzadeh 1997, est unc
0.028	1247.5	BrOBr (g) + H2O (g) → 2 HOBr (g)	Δ_rH°(0 K) = 2.3 ± 1.0 (×1.384) kcal/mol	Lee 1995c
0.026	1264.3	HOBr (g) + [FO]- (g) → HOF (g) + [BrO]- (g)	Δ_rH°(0 K) = -5.61 ± 1.2 kcal/mol	Ruscic G3X
0.025	1265.4	HOBr (g) + [ClO]- (g) → HOCl (g) + [BrO]- (g)	Δ_rH°(0 K) = -0.90 ± 1.0 kcal/mol	Ruscic G4
0.025	1263.4	HOBr (g) + [OH]- (g) → H2O (g) + [BrO]- (g)	Δ_rH°(0 K) = -33.62 ± 1.0 kcal/mol	Ruscic G4
0.022	1264.5	HOBr (g) + [FO]- (g) → HOF (g) + [BrO]- (g)	Δ_rH°(0 K) = -5.46 ± 1.3 kcal/mol	Ruscic CBS-n
0.018	1259.1	HOBr (g) + HCl (g) → HOCl (g) + HBr (g)	Δ_rH°(298.15 K) = 10.81 ± 0.60 (×1.384) kcal/mol	Denis 2006, est unc
0.016	1252.3	HOBr (g) → [HOBr]+ (g)	Δ_rH°(0 K) = 10.63 ± 0.02 eV	Monks 1994a

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. 1.176 of the Thermochemical Network (2024); available at ATcT.anl.gov
4		T. L. Nguyen et al, ongoing studies (2024)
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.