Hydrogen bromide

Formula: BrH
Molecular weight: 80.912
IUPAC Standard InChI: InChI=1S/BrH/h1H
IUPAC Standard InChIKey: CPELXLSAUQHCOX-UHFFFAOYSA-N
CAS Registry Number: 10035-10-6
Chemical structure:
This structure is also available as a 2d Mol file or as a computed 3d SD file
The 3d structure may be viewed using Java or Javascript.
Other names: Hydrobromic acid; Anhydrous hydrobromic acid; HBr; Hydrogen bromide, anhydrous-; Acide bromhydrique; Acido bromidrico; Bromowodor; Bromwasserstoff; Broomwaterstof; UN 1048; UN 1788; Hydrogen monobromide
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Information on this page:
Other data available:
- Phase change data
- Reaction thermochemistry data: reactions 51 to 76
- Henry's Law data
- IR Spectrum
- Mass spectrum (electron ionization)
Data at other public NIST sites:
- Microwave spectra (on physics lab web site)
- Gas Phase Kinetics Database
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Gas phase thermochemistry data

Go To: Top, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering data, Constants of diatomic molecules, References, Notes

Quantity	Value	Units	Method	Reference	Comment
Δ_fH°_gas	-8.674 ± 0.038	kcal/mol	Review	Cox, Wagman, et al., 1984	CODATA Review value
Δ_fH°_gas	-8.709	kcal/mol	Review	Chase, 1998	Data last reviewed in September, 1965
Quantity	Value	Units	Method	Reference	Comment
S°_{gas,1 bar}	47.4904 ± 0.001	cal/mol*K	Review	Cox, Wagman, et al., 1984	CODATA Review value
S°_{gas,1 bar}	47.490	cal/mol*K	Review	Chase, 1998	Data last reviewed in September, 1965

Gas Phase Heat Capacity (Shomate Equation)

C_p° = A + B*t + C*t² + D*t³ + E/t²
H° − H°_298.15= A*t + B*t²/2 + C*t³/3 + D*t⁴/4 − E/t + F − H
S° = A*ln(t) + B*t + C*t²/2 + D*t³/3 − E/(2*t²) + G
C_p = heat capacity (cal/mol*K)
H° = standard enthalpy (kcal/mol)
S° = standard entropy (cal/mol*K)
t = temperature (K) / 1000.

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Temperature (K)	298. to 1100.	1100. to 6000.
A	7.579850	7.860691
B	-3.274360	0.674502
C	5.582140	-0.114253
D	-2.153091	0.007759
E	-0.006873	-0.758833
F	-10.89260	-12.53900
G	57.37161	55.17679
H	-8.710101	-8.710101
Reference	Chase, 1998	Chase, 1998
Comment	Data last reviewed in September, 1965	Data last reviewed in September, 1965

Reaction thermochemistry data

Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, Ion clustering data, Constants of diatomic molecules, References, Notes

Data compiled as indicated in comments:
B - John E. Bartmess
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
MS - José A. Martinho Simões
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. A general reaction search form is also available. Future versions of this site may rely on reaction search pages in place of the enumerated reaction displays seen below.

Reactions 1 to 50

+ Hydrogen bromide = ( • )

By formula: Br^- + HBr = (Br^- • HBr)

Bond type: Hydrogen bond (negative ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	20.6 ± 2.0	kcal/mol	TDAs	Caldwell and Kebarle, 1985	gas phase; B,M
Δ_rH°	17.5	kcal/mol	FA	Davidson, Fehsenfeld, et al., 1977	gas phase; From thermochemical cycle,switching reaction(Br-/NO3-HNO3/HBr); DG>, Δ_rH>; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	22.3	cal/mol*K	PHPMS	Caldwell and Kebarle, 1985	gas phase; M
Δ_rS°	22.	cal/mol*K	FA	Davidson, Fehsenfeld, et al., 1977	gas phase; From thermochemical cycle,switching reaction(Br-/NO3-HNO3/HBr); DG>, Δ_rH>; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	13.9 ± 2.6	kcal/mol	TDAs	Caldwell and Kebarle, 1985	gas phase; B

Free energy of reaction

Δ_rG° (kcal/mol)	T (K)	Method	Reference	Comment
9.4	367.	FA	Davidson, Fehsenfeld, et al., 1977	gas phase; From thermochemical cycle,switching reaction(Br-/NO3-HNO3/HBr); DG>, Δ_rH>; M

+ = Hydrogen bromide

By formula: Br^- + H⁺ = HBr

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	323.540 ± 0.050	kcal/mol	D-EA	Blondel, Cacciani, et al., 1989	gas phase; reported: 27129.170±0.015 cm-1; B
Δ_rH°	323.4 ± 2.1	kcal/mol	G+TS	Taft and Bordwell, 1988	gas phase; B
Δ_rH°	320.60	kcal/mol	N/A	Check, Faust, et al., 2001	gas phase; F-; ; ΔS(acid)=19.2; ΔS(EA)=6.4; B
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	318.30 ± 0.15	kcal/mol	H-TS	Blondel, Cacciani, et al., 1989	gas phase; reported: 27129.170±0.015 cm-1; B
Δ_rG°	318.2 ± 2.0	kcal/mol	IMRE	Taft and Bordwell, 1988	gas phase; B
Δ_rG°	315.40	kcal/mol	N/A	Check, Faust, et al., 2001	gas phase; F-; ; ΔS(acid)=19.2; ΔS(EA)=6.4; B

C₈H₆MoO₃ (cr) + (solution) = Hydrogen bromide (solution) + (cr)

By formula: C₈H₆MoO₃ (cr) + Br₂ (solution) = HBr (solution) + C₈H₅BrMoO₃ (cr)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-35.8 ± 2.8	kcal/mol	N/A	Nolan, López de la Vega, et al., 1986	solvent: Carbon tetrachloride; The reaction enthalpy was calculated Nolan, López de la Vega, et al., 1986 from the experimental values for the enthalpies of the following reactions: Mo(Cp)(CO)3(H)(cr) + 2Br2(solution) = Mo(Cp)(CO)2(Br)3(solution) + HBr(solution) + CO(solution), -60.7 ± 2.0 kcal/mol, and Mo(Cp)(CO)3(Br)(cr) + Br2(solution) = Mo(Cp)(CO)2(Br)3(solution) + CO(solution), -24.9 ± 2.0 kcal/mol; MS

+ Hydrogen bromide = ( • )

By formula: NO₃^- + HBr = (NO₃^- • HBr)

Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	23.	cal/mol*K	N/A	Davidson, Fehsenfeld, et al., 1977	gas phase; switching reaction(NO3-)HNO3, Entropy change calculated or estimated, DG<, Δ_rH<; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	17.4 ± 3.9	kcal/mol	TDEq	Davidson, Fehsenfeld, et al., 1977	gas phase; Anchored to HBr..Br- in Caldwell and Kebarle, 1985.; B

Free energy of reaction

Δ_rG° (kcal/mol)	T (K)	Method	Reference	Comment
12.7	367.	FA	Davidson, Fehsenfeld, et al., 1977	gas phase; switching reaction(NO3-)HNO3, Entropy change calculated or estimated, DG<, Δ_rH<; M

+ Hydrogen bromide = ( • )

By formula: I^- + HBr = (I^- • HBr)

Bond type: Hydrogen bond (negative ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	16.1 ± 2.0	kcal/mol	TDEq	Caldwell and Kebarle, 1985	gas phase; B,M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	19.6	cal/mol*K	PHPMS	Caldwell and Kebarle, 1985	gas phase; switching reaction(I-)SO2; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	10.2 ± 2.6	kcal/mol	TDEq	Caldwell and Kebarle, 1985	gas phase; B

Free energy of reaction

Δ_rG° (kcal/mol)	T (K)	Method	Reference	Comment
10.2	300.	PHPMS	Caldwell and Kebarle, 1985	gas phase; switching reaction(I-)SO2; M

Hydrogen bromide + =

By formula: HBr + C₃H₆ = C₃H₇Br

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-20.43	kcal/mol	Cm	Lacher, Kianpour, et al., 1957	gas phase; ALS
Δ_rH°	-20.050	kcal/mol	Cm	Lacher, Lea, et al., 1950	gas phase; Heat of hydrobromination at 367°K; ALS
Δ_rH°	-20.10 ± 0.14	kcal/mol	Cm	Lacher, Walden, et al., 1950	gas phase; Reanalyzed by Cox and Pilcher, 1970, Original value = -20.17 ± 0.24 kcal/mol; Heat of hydrobromination; ALS

( • ) + Hydrogen bromide = ( • • )

By formula: (Br^- • O₂S) + HBr = (Br^- • HBr • O₂S)

Bond type: Hydrogen bond (negative ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	12.2	kcal/mol	PHPMS	Caldwell and Kebarle, 1985	gas phase; From thermochemical cycle,switching reaction(Br- HBr)SO2; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	19.2	cal/mol*K	PHPMS	Caldwell and Kebarle, 1985	gas phase; From thermochemical cycle,switching reaction(Br- HBr)SO2; M

( • ) + Hydrogen bromide = ( • • )

By formula: (NO₃^- • HNO₃) + HBr = (NO₃^- • HBr • HNO₃)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	16.0	kcal/mol	FA	Davidson, Fehsenfeld, et al., 1977	gas phase; switching reaction(NO3-)2HNO3; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	22.9	cal/mol*K	FA	Davidson, Fehsenfeld, et al., 1977	gas phase; switching reaction(NO3-)2HNO3; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	9.2	kcal/mol	FA	Davidson, Fehsenfeld, et al., 1977	gas phase; switching reaction(NO3-)2HNO3; M

Hydrogen bromide (g) + CH₃BrMg (solution) = (solution) + Br₂Mg (solution)

By formula: HBr (g) + CH₃BrMg (solution) = CH₄ (solution) + Br₂Mg (solution)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-65.61 ± 0.53	kcal/mol	RSC	Holm, 1981	solvent: Diethyl ether; The enthalpy of formation was calculated using the assumptions and the auxiliary data in Holm, 1981, except for the organic compound, whose enthalpy of formation was quoted from Pedley, 1994; MS

( • Hydrogen bromide ) + = ( • 2)

By formula: (Br^- • HBr) + HBr = (Br^- • 2HBr)

Bond type: Hydrogen bond (negative ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	11.0	kcal/mol	PHPMS	Caldwell and Kebarle, 1985	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	17.0	cal/mol*K	PHPMS	Caldwell and Kebarle, 1985	gas phase; M

+ 0.5 = Hydrogen bromide + + 0.5

By formula: C₄H₄BrNO₂ + 0.5H₄N₂ = HBr + C₄H₅NO₂ + 0.5N₂

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-62.22 ± 0.11	kcal/mol	Cm	Howard and Skinner, 1966	solid phase; solvent: Aqueous solution; Reanalyzed by Pedley, Naylor, et al., 1986, Original value = -62.55 ± 0.11 kcal/mol; ALS

+ Hydrogen bromide = ( • )

By formula: CH₃⁺ + HBr = (CH₃⁺ • HBr)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	55.4	kcal/mol	PHPMS	McMahon, Heinis, et al., 1988	gas phase; switching reaction(CH3+)N2, Entropy change calculated or estimated, uses MCA(N2) = 48.3 kcal/mol; Foster, Williamson, et al., 1974; M

C₄H₉Li (l) + Hydrogen bromide (g) = (l) + (cr)

By formula: C₄H₉Li (l) + HBr (g) = C₄H₁₀ (l) + BrLi (cr)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-89.39 ± 0.48	kcal/mol	RSC	Holm, 1974	Please also see Pedley and Rylance, 1977. The reaction enthalpy was quoted from Pedley and Rylance, 1977. See Liebman, Martinho Simões, et al., 1995 for comments; MS

Hydrogen bromide (g) + (cr) = (g) + (cr)

By formula: HBr (g) + CH₃Li (cr) = CH₄ (g) + BrLi (cr)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-75.84 ± 0.48	kcal/mol	RSC	Holm, 1974	Please also see Pedley and Rylance, 1977. The reaction enthalpy was quoted from Pedley and Rylance, 1977. See Liebman, Martinho Simões, et al., 1995 for comments; MS

Hydrogen bromide (g) + (cr) = (g) + (cr)

By formula: HBr (g) + C₂H₅Li (cr) = C₂H₆ (g) + BrLi (cr)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-82.62 ± 0.48	kcal/mol	RSC	Holm, 1974	Please also see Pedley and Rylance, 1977. The reaction enthalpy was quoted from Pedley and Rylance, 1977. See Liebman, Martinho Simões, et al., 1995 for comments; MS

Hydrogen bromide (g) + C₄H₉Li (l) = (l) + (cr)

By formula: HBr (g) + C₄H₉Li (l) = C₄H₁₀ (l) + BrLi (cr)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-84.30 ± 0.48	kcal/mol	RSC	Holm, 1974	Please also see Pedley and Rylance, 1977. The reaction enthalpy was quoted from Pedley and Rylance, 1977. See Liebman, Martinho Simões, et al., 1995 for comments; MS

( • Hydrogen bromide ) + = ( • • )

By formula: (NO₃^- • HBr) + HNO₃ = (NO₃^- • HNO₃ • HBr)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	16.0 ± 2.0	kcal/mol	TDEq	Davidson, Fehsenfeld, et al., 1977	gas phase; B
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	9.6 ± 2.8	kcal/mol	TDEq	Davidson, Fehsenfeld, et al., 1977	gas phase; B

Hydrogen bromide + =

By formula: HBr + C₄H₈ = C₄H₉Br

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-18.42 ± 0.12	kcal/mol	Cm	Lacher, Billings, et al., 1952	gas phase; Reanalyzed by Cox and Pilcher, 1970, Original value = -18.3 ± 1.6 kcal/mol; Heat of Hydrobromination at 373 K; ALS

Hydrogen bromide + =

By formula: HBr + C₄H₈ = C₄H₉Br

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-17.26 ± 0.12	kcal/mol	Cm	Lacher, Billings, et al., 1952	gas phase; Reanalyzed by Cox and Pilcher, 1970, Original value = -17.3 ± 1.4 kcal/mol; Heat of hydrobromination at 373 K; ALS

Hydrogen bromide + =

By formula: HBr + C₄H₈ = C₄H₉Br

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-20.04 ± 0.12	kcal/mol	Cm	Lacher, Billings, et al., 1952	gas phase; Reanalyzed by Cox and Pilcher, 1970, Original value = -20.1 ± 1.8 kcal/mol; Heat of hydrobromination at 367 K; ALS

Hydrogen bromide + =

By formula: HBr + C₃H₆ = C₃H₇Br

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-25.77 ± 0.32	kcal/mol	Cm	Lacher, Kianpour, et al., 1957	gas phase; ALS
Δ_rH°	-22.69 ± 0.16	kcal/mol	Cm	Lacher, Walden, et al., 1950	gas phase; Heat of hydrobromination; ALS

( • Hydrogen bromide ) + = ( • • )

By formula: (Br^- • HBr) + O₂S = (Br^- • O₂S • HBr)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	10.9	kcal/mol	PHPMS	Caldwell and Kebarle, 1985	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	18.9	cal/mol*K	PHPMS	Caldwell and Kebarle, 1985	gas phase; M

+ = Hydrogen bromide +

By formula: C₂H₃BrO + H₂O = HBr + C₂H₄O₂

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-23.31	kcal/mol	Cm	Devore and O'Neal, 1969	liquid phase; Heat of hydrolysis; ALS
Δ_rH°	-23.06	kcal/mol	Cm	Carson and Skinner, 1949	liquid phase; ALS

+ = Hydrogen bromide +

By formula: H₂ + C₃H₇Br = HBr + C₃H₈

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-10.85 ± 0.22	kcal/mol	Chyd	Davies, Lacher, et al., 1965	gas phase; Reanalyzed by Cox and Pilcher, 1970, Original value = -10.77 kcal/mol; ALS

Hydrogen bromide + = +

By formula: HBr + C₇H₇Br = C₇H₈ + Br₂

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	8.1 ± 1.0	kcal/mol	Eqk	Benson and Buss, 1957	gas phase; Reanalyzed by Cox and Pilcher, 1970, Original value = 8.0 ± 0.9 kcal/mol; ALS

= Hydrogen bromide +

By formula: C₃H₆Br₂ = HBr + C₃H₅Br

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	15.5	kcal/mol	Eqk	Levanova, Rodova, et al., 1983	liquid phase; Flow reactor; ALS
Δ_rH°	16.7 ± 0.2	kcal/mol	Eqk	Sharonov and Rozhnov, 1971	gas phase; ALS

+ 218.5 + 11.25 + = Hydrogen bromide + 13 + 1.5

By formula: CBrN₃O₆ + 218.5H₂O + 11.25O₂ + C₁₂H₁₄O₄ = HBr + 13CO₂ + 1.5N₂

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-1517.74 ± 0.24	kcal/mol	Ccr	Carpenter, Zimmer, et al., 1970	liquid phase; The HBr is in 225H2O; ALS

= Hydrogen bromide +

By formula: C₂H₅Br = HBr + C₂H₄

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	19.20 ± 0.50	kcal/mol	Eqk	Lane, Linnett, et al., 1953	gas phase; Reanalyzed by Cox and Pilcher, 1970, Original value = 19.1 kcal/mol; ALS

C₈H₆MoO₃ (cr) + 2 (solution) = C₇H₅Br₃MoO₂ (solution) + Hydrogen bromide (solution) + (solution)

By formula: C₈H₆MoO₃ (cr) + 2Br₂ (solution) = C₇H₅Br₃MoO₂ (solution) + HBr (solution) + CO (solution)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-60.7 ± 2.0	kcal/mol	RSC	Nolan, López de la Vega, et al., 1986	solvent: Carbon tetrachloride; MS

+ = Hydrogen bromide +

By formula: C₃H₄O₄ + Br₂ = HBr + C₃H₃BrO₄

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-15.8 ± 0.69	kcal/mol	Cm	Koros, Orban, et al., 1979	liquid phase; solvent: Sulfuric acid (1M); Bromination; ALS

+ = Hydrogen bromide +

By formula: C₇H₉NO + C₇H₅BrO = HBr + C₁₄H₁₃NO₂

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-41.0 ± 0.2	kcal/mol	Cac	Kiselev, Khuzyasheva, et al., 1979	liquid phase; solvent: Benzene; ALS

+ = Hydrogen bromide +

By formula: C₇H₉N + C₇H₅BrO = HBr + C₁₄H₁₃NO

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-40.7 ± 0.2	kcal/mol	Cac	Kiselev, Khuzyasheva, et al., 1979	liquid phase; solvent: Benzene; ALS

Hydrogen bromide + = +

By formula: HBr + C₃H₅BrO = C₃H₆O + Br₂

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	7.4 ± 2.0	kcal/mol	Eqk	King, Golden, et al., 1971	gas phase; Heat of bromination at 516-618 K; ALS

Hydrogen bromide + =

By formula: HBr + C₂F₄ = C₂HBrF₄

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-32.92 ± 0.18	kcal/mol	Cm	Lacher, Lea, et al., 1950	gas phase; Heat of hydrobromination at 367°K; ALS

+ = Hydrogen bromide +

By formula: C₇H₅BrO + C₆H₇N = HBr + C₁₃H₁₁NO

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-38.6 ± 0.2	kcal/mol	Cac	Kiselev, Khuzyasheva, et al., 1979	liquid phase; solvent: Benzene; ALS

Hydrogen bromide + =

By formula: HBr + C₂ClF₃ = C₂HBrClF₃

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-26.07 ± 0.23	kcal/mol	Cm	Lacher, Lea, et al., 1950	gas phase; Heat of hydrobromination at 367°K; ALS

+ = 2 Hydrogen bromide +

By formula: CBr₂O + H₂O = 2HBr + CO₂

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-49.06 ± 0.16	kcal/mol	Cm	Anthoney, Finch, et al., 1970	liquid phase; Heat of hydrolysis; ALS

= Hydrogen bromide +

By formula: C₂H₄BrCl = HBr + C₂H₃Cl

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	19.9 ± 0.2	kcal/mol	Eqk	Busheva, Levanova, et al., 1980	gas phase; Dehydrohalogenation; ALS

Hydrogen bromide (g) + C₂H₃BrMg (solution) = (solution) + Br₂Mg (solution)

By formula: HBr (g) + C₂H₃BrMg (solution) = C₂H₄ (solution) + Br₂Mg (solution)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-70.29 ± 0.53	kcal/mol	RSC	Holm, 1981	solvent: Tetrahydrofuran; MS

C₄H₉BrMg (solution) + Hydrogen bromide (g) = (solution) + Br₂Mg (solution)

By formula: C₄H₉BrMg (solution) + HBr (g) = C₄H₁₀ (solution) + Br₂Mg (solution)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-69.91 ± 0.53	kcal/mol	RSC	Holm, 1981	solvent: Diethyl ether; MS

C₄H₉BrMg (solution) + Hydrogen bromide (g) = (solution) + Br₂Mg (solution)

By formula: C₄H₉BrMg (solution) + HBr (g) = C₄H₁₀ (solution) + Br₂Mg (solution)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-73.11 ± 0.53	kcal/mol	RSC	Holm, 1981	solvent: Diethyl ether; MS

C₅H₁₁BrMg (solution) + Hydrogen bromide (g) = (solution) + Br₂Mg (solution)

By formula: C₅H₁₁BrMg (solution) + HBr (g) = C₅H₁₂ (solution) + Br₂Mg (solution)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-73.21 ± 0.53	kcal/mol	RSC	Holm, 1981	solvent: Diethyl ether; MS

C₁₉H₁₅BrMg (solution) + Hydrogen bromide (g) = (solution) + Br₂Mg (solution)

By formula: C₁₉H₁₅BrMg (solution) + HBr (g) = C₁₉H₁₆ (solution) + Br₂Mg (solution)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-55.21 ± 0.53	kcal/mol	RSC	Holm, 1981	solvent: Diethyl ether; MS

+ = Hydrogen bromide +

By formula: C₃H₅Br + H₂O = HBr + C₃H₆O

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-3.7	kcal/mol	Cm	Gellner and Skinner, 1949	liquid phase; Heat of hydrolysis; ALS

+ = Hydrogen bromide +

By formula: C₇H₇Br + H₂O = HBr + C₇H₈O

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-1.9	kcal/mol	Cm	Gellner and Skinner, 1949	liquid phase; Heat of hydrloysis; ALS

C₃H₇BrMg (solution) + Hydrogen bromide (g) = (solution) + Br₂Mg (solution)

By formula: C₃H₇BrMg (solution) + HBr (g) = C₃H₈ (solution) + Br₂Mg (solution)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-73.11 ± 0.53	kcal/mol	RSC	Holm, 1981	solvent: Diethyl ether; MS

+ = Hydrogen bromide +

By formula: C₇H₅BrO + H₂O = HBr + C₇H₆O₂

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-27.04	kcal/mol	Cm	Carson, Pritchard, et al., 1950	liquid phase; Heat of hydrolysis; ALS

Hydrogen bromide (g) + C₂H₅BrMg (solution) = (solution) + Br₂Mg (solution)

By formula: HBr (g) + C₂H₅BrMg (solution) = C₂H₆ (solution) + Br₂Mg (solution)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-71.51 ± 0.53	kcal/mol	RSC	Holm, 1981	solvent: Diethyl ether; MS

= Hydrogen bromide + C₁₀H₁₅N

By formula: C₁₀H₁₆N.Br = HBr + C₁₀H₁₅N

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-21.0 ± 0.9	kcal/mol	Cm	Arnett and Wernett, 1993	liquid phase; solvent: DMSO; ALS

Hydrogen bromide + =

By formula: HBr + C₉H₁₀ = C₉H₁₁Br

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-15.2 ± 1.3	kcal/mol	Cm	Nesterova, Kovzel, et al., 1977	liquid phase; Hydrobromination; ALS

Gas phase ion energetics data

Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Ion clustering data, Constants of diatomic molecules, References, Notes

Data evaluated as indicated in comments:
HL - Edward P. Hunter and Sharon G. Lias
L - Sharon G. Lias

Data compiled as indicated in comments:
B - John E. Bartmess
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron

View reactions leading to HBr⁺ (ion structure unspecified)

Quantity	Value	Units	Method	Reference	Comment
IE (evaluated)	11.68 ± 0.03	eV	N/A	N/A	L
Quantity	Value	Units	Method	Reference	Comment
Proton affinity (review)	139.6	kcal/mol	N/A	Hunter and Lias, 1998	HL
Quantity	Value	Units	Method	Reference	Comment
Gas basicity	133.3	kcal/mol	N/A	Hunter and Lias, 1998	HL

Ionization energy determinations

IE (eV)	Method	Reference	Comment
11.71	PE	Kimura, Katsumata, et al., 1981	LLK
11.66 ± 0.02	PI	Tiedemann, Anderson, et al., 1979	LLK
11.67	EVAL	Huber and Herzberg, 1979	LLK
11.645 ± 0.005	PE	Delwiche, Natalis, et al., 1973	LLK
11.677 ± 0.004	DER	Haugh and Bayes, 1971	LLK
11.67 ± 0.01	PE	Lempka, Passmore, et al., 1968	RDSH
11.71 ± 0.01	PE	Frost, McDowell, et al., 1967	RDSH
11.68 ± 0.03	PI	Watanabe, 1957	RDSH

De-protonation reactions

+ = Hydrogen bromide

By formula: Br^- + H⁺ = HBr

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	323.540 ± 0.050	kcal/mol	D-EA	Blondel, Cacciani, et al., 1989	gas phase; reported: 27129.170±0.015 cm-1; B
Δ_rH°	323.4 ± 2.1	kcal/mol	G+TS	Taft and Bordwell, 1988	gas phase; B
Δ_rH°	320.60	kcal/mol	N/A	Check, Faust, et al., 2001	gas phase; F-; ; ΔS(acid)=19.2; ΔS(EA)=6.4; B
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	318.30 ± 0.15	kcal/mol	H-TS	Blondel, Cacciani, et al., 1989	gas phase; reported: 27129.170±0.015 cm-1; B
Δ_rG°	318.2 ± 2.0	kcal/mol	IMRE	Taft and Bordwell, 1988	gas phase; B
Δ_rG°	315.40	kcal/mol	N/A	Check, Faust, et al., 2001	gas phase; F-; ; ΔS(acid)=19.2; ΔS(EA)=6.4; B

Ion clustering data

Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, Constants of diatomic molecules, References, Notes

Data compiled as indicated in comments:
B - John E. Bartmess
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias

Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. Searches may be limited to ion clustering reactions. A general reaction search form is also available.

Clustering reactions

+ Hydrogen bromide = ( • )

By formula: Br^- + HBr = (Br^- • HBr)

Bond type: Hydrogen bond (negative ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	20.6 ± 2.0	kcal/mol	TDAs	Caldwell and Kebarle, 1985	gas phase; B,M
Δ_rH°	17.5	kcal/mol	FA	Davidson, Fehsenfeld, et al., 1977	gas phase; From thermochemical cycle,switching reaction(Br-/NO3-HNO3/HBr); DG>, Δ_rH>; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	22.3	cal/mol*K	PHPMS	Caldwell and Kebarle, 1985	gas phase; M
Δ_rS°	22.	cal/mol*K	FA	Davidson, Fehsenfeld, et al., 1977	gas phase; From thermochemical cycle,switching reaction(Br-/NO3-HNO3/HBr); DG>, Δ_rH>; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	13.9 ± 2.6	kcal/mol	TDAs	Caldwell and Kebarle, 1985	gas phase; B

Free energy of reaction

Δ_rG° (kcal/mol)	T (K)	Method	Reference	Comment
9.4	367.	FA	Davidson, Fehsenfeld, et al., 1977	gas phase; From thermochemical cycle,switching reaction(Br-/NO3-HNO3/HBr); DG>, Δ_rH>; M

( • Hydrogen bromide ) + = ( • 2)

By formula: (Br^- • HBr) + HBr = (Br^- • 2HBr)

Bond type: Hydrogen bond (negative ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	11.0	kcal/mol	PHPMS	Caldwell and Kebarle, 1985	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	17.0	cal/mol*K	PHPMS	Caldwell and Kebarle, 1985	gas phase; M

( • ) + Hydrogen bromide = ( • • )

By formula: (Br^- • O₂S) + HBr = (Br^- • HBr • O₂S)

Bond type: Hydrogen bond (negative ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	12.2	kcal/mol	PHPMS	Caldwell and Kebarle, 1985	gas phase; From thermochemical cycle,switching reaction(Br- HBr)SO2; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	19.2	cal/mol*K	PHPMS	Caldwell and Kebarle, 1985	gas phase; From thermochemical cycle,switching reaction(Br- HBr)SO2; M

+ Hydrogen bromide = ( • )

By formula: CH₃⁺ + HBr = (CH₃⁺ • HBr)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	55.4	kcal/mol	PHPMS	McMahon, Heinis, et al., 1988	gas phase; switching reaction(CH3+)N2, Entropy change calculated or estimated, uses MCA(N2) = 48.3 kcal/mol; Foster, Williamson, et al., 1974; M

HBr⁺ + Hydrogen bromide = (HBr⁺ • )

By formula: HBr⁺ + HBr = (HBr⁺ • HBr)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	23.	kcal/mol	PI	Tiedemann, Anderson, et al., 1979	gas phase; M

+ Hydrogen bromide = ( • )

By formula: I^- + HBr = (I^- • HBr)

Bond type: Hydrogen bond (negative ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	16.1 ± 2.0	kcal/mol	TDEq	Caldwell and Kebarle, 1985	gas phase; B,M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	19.6	cal/mol*K	PHPMS	Caldwell and Kebarle, 1985	gas phase; switching reaction(I-)SO2; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	10.2 ± 2.6	kcal/mol	TDEq	Caldwell and Kebarle, 1985	gas phase; B

Free energy of reaction

Δ_rG° (kcal/mol)	T (K)	Method	Reference	Comment
10.2	300.	PHPMS	Caldwell and Kebarle, 1985	gas phase; switching reaction(I-)SO2; M

+ Hydrogen bromide = ( • )

By formula: NO₃^- + HBr = (NO₃^- • HBr)

Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	23.	cal/mol*K	N/A	Davidson, Fehsenfeld, et al., 1977	gas phase; switching reaction(NO3-)HNO3, Entropy change calculated or estimated, DG<, Δ_rH<; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	17.4 ± 3.9	kcal/mol	TDEq	Davidson, Fehsenfeld, et al., 1977	gas phase; Anchored to HBr..Br- in Caldwell and Kebarle, 1985.; B

Free energy of reaction

Δ_rG° (kcal/mol)	T (K)	Method	Reference	Comment
12.7	367.	FA	Davidson, Fehsenfeld, et al., 1977	gas phase; switching reaction(NO3-)HNO3, Entropy change calculated or estimated, DG<, Δ_rH<; M

( • ) + Hydrogen bromide = ( • • )

By formula: (NO₃^- • HNO₃) + HBr = (NO₃^- • HBr • HNO₃)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	16.0	kcal/mol	FA	Davidson, Fehsenfeld, et al., 1977	gas phase; switching reaction(NO3-)2HNO3; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	22.9	cal/mol*K	FA	Davidson, Fehsenfeld, et al., 1977	gas phase; switching reaction(NO3-)2HNO3; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	9.2	kcal/mol	FA	Davidson, Fehsenfeld, et al., 1977	gas phase; switching reaction(NO3-)2HNO3; M

Constants of diatomic molecules

Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering data, References, Notes

Data compiled by: Klaus P. Huber and Gerhard H. Herzberg

Data collected through December, 1976

Symbols used in the table of constants
Symbol	Meaning
State	electronic state and / or symmetry symbol
T_e	minimum electronic energy (cm^-1)
ω_e	vibrational constant – first term (cm^-1)
ω_ex_e	vibrational constant – second term (cm^-1)
ω_ey_e	vibrational constant – third term (cm^-1)
B_e	rotational constant in equilibrium position (cm^-1)
α_e	rotational constant – first term (cm^-1)
γ_e	rotation-vibration interaction constant (cm^-1)
D_e	centrifugal distortion constant (cm^-1)
β_e	rotational constant – first term, centrifugal force (cm^-1)
r_e	internuclear distance (Å)
Trans.	observed transition(s) corresponding to electronic state
ν₀₀	position of 0-0 band (units noted in table)

Diatomic constants for H⁸¹Br
State	T_e	ω_e	ω_ex_e	ω_ey_e	B_e	α_e	γ_e	D_e	β_e	r_e	Trans.	ν₀₀
Numerous absorption bands above 11400 cm^-1, tentatively assigned to higher members of two Rydberg series starting with L and M and converging to A ²Σ⁺ of Hbr⁺; I.P.[A ²Σ⁺, v=0]=123373 cm^-1 (15.296₄ eV).
M (¹Σ⁺)	(109473)	[1308] 1									M ← X	108814
M (¹Σ⁺)	↳missing citation
L (¹Σ⁺, 1Π)	(104201)	[1262] 2									L ← X	103519
	↳missing citation
	3
	↳Barrow and Stamper, 1961; Stamper, 1962
State	T_e	ω_e	ω_ex_e	ω_ey_e	B_e	α_e	γ_e	D_e	β_e	r_e	Trans.	ν₀₀
K 6 1	(83902)	(2518) 4			[8.195]			[22.0E-4]		[1.437₅]	K ← X R	83847.9 5 Z
K 6 1	↳Stamper, 1962
J 6 1	(81243)	(2502) 4			[8.02₇] 7			[3.6₁E-4]		[1.453]	J ← X R	81180.7 8 Z
J 6 1	↳missing citation
I 6 1	80436	(2525) 4			[8.16₉] 9			[10.₄E-4]		[1.440]	I ← X R	80385.6 10 Z
I 6 1	↳missing citation
g (³Σ^-)0⁺	(79253.2) 11				[7.6₃] 12			-17E-4		[1.49]	g ← X R	77940.₀ Z
g (³Σ^-)0⁺	↳missing citation; missing citation
State	T_e	ω_e	ω_ex_e	ω_ey_e	B_e	α_e	γ_e	D_e	β_e	r_e	Trans.	ν₀₀
F ¹Δ	(78322.3) 11				[8.20]					[1.43₇]	F ← X R	77009.1 Z
F ¹Δ	↳missing citation
f₁ ³Δ₁	(76814) 11	[2299.7] Z			8.02₇	0.21₃				1.453	f₁ ← X R	76650.9 Z
f₁ ³Δ₁	↳Barrow and Stamper, 1961; missing citation
D ¹Π	(76310) 13	[2405.5] Z			8.12₅	0.21				1.444	D ← X R	76199.4 Z
D ¹Π	↳missing citation; missing citation
d₀ ³Π₀	(76193)	[2418.5] Z			[7.624] 14	(0.32)				[1.490₄]	d₀ ← X R	76088.8 Z
d₀ ³Π₀	↳Barrow and Stamper, 1961; missing citation
State	T_e	ω_e	ω_ex_e	ω_ey_e	B_e	α_e	γ_e	D_e	β_e	r_e	Trans.	ν₀₀
E (³Σ⁺)0⁺	(76691) 11				[7.34] 15					[1.51₉]	E ← X R	75378
E (³Σ⁺)0⁺	↳Ginter and Tilford, 1971
V ¹Σ⁺	(75800) 16	(790) 17									V ↔ X 18 R	(74900)
V ¹Σ⁺	↳Stamper and Barrow, 1961; missing citation
f₂ ³Δ₂	[75533.8] 11				[8.67₅] 19			[16.₅E-4] 19		[1.397] 5	f₂ ← X R	74220.6 Z
f₂ ³Δ₂	↳Barrow and Stamper, 1961; missing citation
f₃ ³Δ₃	[75403.1] 11 20				[7.41]			[-7.6E-4]		[1.51₂] 5	f₃ ← X R	74089.9 Z
f₃ ³Δ₃	↳missing citation
State	T_e	ω_e	ω_ex_e	ω_ey_e	B_e	α_e	γ_e	D_e	β_e	r_e	Trans.	ν₀₀
e ³Σ⁺	[75053] 11 21										e ← X R	73740
e ³Σ⁺	↳Ginter and Tilford, 1971
d₁ ³Π₁	[74855] 13 22										d₁ ← X R	73542
d₁ ³Π₁	↳Barrow and Stamper, 1961; Ginter and Tilford, 1971
d₂ ³Π₂	[74753] 13 22										d₂ ← X R	73440
d₂ ³Π₂	↳Barrow and Stamper, 1961; Ginter and Tilford, 1971
C ¹Π	70578 23	2552 Z	52		7.89	0.30				1.46₅	C ← X 24 R	70527.6 Z
C ¹Π	↳Barrow and Stamper, 1961; missing citation
State	T_e	ω_e	ω_ex_e	ω_ey_e	B_e	α_e	γ_e	D_e	β_e	r_e	Trans.	ν₀₀
b₀ ³Π₀ 0⁺	(68998) 23	[2452]			[7.996] 25					[1.455]	b₀ ← X R	68911.2 Z
b₀ ³Π₀ 0⁺	↳Barrow and Stamper, 1961; missing citation
b₀ ³Π₀ 0^-											b₀ ← X R	68904 26 H
b₀ ³Π₀ 0^-	↳Barrow and Stamper, 1961; missing citation
b₁ ³Π₁	(67180) 23	[2444.2] Z			8.14₈ 25	0.29₂				1.442	b₁ ← X R	67088.4 Z
b₁ ³Π₁	↳missing citation; missing citation
b₂ ³Π₂	[67663.0] 23				[7.80₅] 25					[1.473]	b₂ ← X R	66349.8 Z
b₂ ³Π₂	↳Barrow and Stamper, 1961; missing citation
State	T_e	ω_e	ω_ex_e	ω_ey_e	B_e	α_e	γ_e	D_e	β_e	r_e	Trans.	ν₀₀
A (¹Π) 28	27										A ← X
A (¹Π) 28	↳Bates, Halford, et al., 1935; Goodeve and Taylor, 1935; Datta and Chakravarty, 1941; Romand, 1949; Huebert and Martin, 1968
X ¹Σ⁺	0	2648.975 29 Z	45.217₅ 30	-0.0029	8.46488₄ X	0.23328 31		3.457₅E-4 32		1.41443₅ 33
	↳Rank, Fink, et al., 1965
	Rotation spectrum 34 35
	↳Hansler and Oetjen, 1953; Jones and Gordy, 1964; Van Dijk and Dymanus, 1969
	Raman sp. 36
	↳Cherlow, Hyatt, et al., 1975
	Mol. beam el. reson. 37
	↳Dabbousi, Meerts, et al., 1973

Notes

v=0...4 observed. Assigned as 4pσ4pπ⁴ 6sσ. 40

v=0...3 observed. Assigned as 4pσ4pπ⁴ 5pσ and/or 5pπ. 40

Further absorption bands of doubtful assignment between 75200 and 83600 cm^-1.

From the observed HBr-DBr isotope shift assuming that the observed bands are 0-0 bands.

Band [37] of Stamper, 1962.

I, J, K correspond to absorption bands with clear analogues in DBr.

Ω-type doubling, Δν_ef = +0.14₂J(J+1)- ...; B and D represent average values.

Band [28] of Barrow and Stamper, 1961. Sharp P, Q, R branches; the Q levels appear to be predissociated for J«gte»14.

missing note

Band [26] of Barrow and Stamper, 1961.

Configuration ... σ²π³ 5pπ.

Perturbed at high J.

Configuration ... σ²π³ 5pσ.

Slightly diffuse lines.

Perturbed.

Derived from H⁺ + Br^-; configuration ... σπ⁴σ*.

Bands in emission above 46500 cm^-1, in absorption above 75700. Incomplete analysis.

Heavily perturbed extensive band system. Absorption lines above 75923 cm^-1 are diffuse. B' varies irregularly between 3.4 and 4.5 cm^-1.

Average values for the two Ω-type doubling components.

Weak transition.

Very diffuse, unresolved band.

Diffuse band, rotational structure unresolved.

Configuration ... σ²π³ 5sσ.

Very strong absorption, lines are diffuse.

Diffuse rotational structure.

Diffuse Q head.

Continous absorption statring at ~35000 with maximum at 56400 cm^-1.

Configuration ... σ²π³ σ*.

These are Y₁₀ and Y₀₁ values; applying Dunham corrections Rank, Fink, et al., 1965 obtain w_e = 2649.21₅, B_e = 8.46506₅. Additional corrections (adiabatic, non-adiabatic) are discussed by Bunker, 1972. The microwave B₀ values of Jones and Gordy, 1964 was included in the evaluation of B_e. See also 42 37

missing note

+0.000873₅(v+1/2)² - 0.000120(v+1/2)³.

-0.039₇E-4(v+1/2) + 0.0038(v+1/2)²; H_v = 7.63E-9 - 0.55E-9(v+1/2).

Rot.-vibr. Sp. 42 35

Absolute intensities have been measured by Chamberlain and Gebbie, 1965.

For observations and measurements of pressure-induced bands and pure rotation lines (ΔJ=2) see Atwood, Vu, et al., 1967, Weiss and Cole, 1967. The pressure broadening of the lines has been studied by Babrov, 1964, Pourcin, Bachet, et al., 1967.

Raman cross sections in gaseous HBr.

The following constants (as well as corresponding values for H⁷⁹Br) are given in Dabbousi, Meerts, et al., 1973: -μ_el(v=0,J=1) = 0.8265 D [in a later paper van Dijk and Dymanus, 1974 derive 0.8282 D from Stark effect of rotation spectrum]; -quadrupole and other hyperfine coupling constants; -g_J = 0.3712. These constants supersede earlier values of Schurin and Rollefson, 1957, Jones and Gordy, 1964, Tokuhiro, 1967, Van Dijk and Dymanus, 1969, van Dijk and Dymanus, 1970.

From D₀⁰(H₂), D₀⁰(Br₂), and ΔH_f0 (HBr;from gaseous H₂,Br₂).

Average value from photoionization Watanabe, 1957 and photoelectron spectra Frost, McDowell, et al., 1967, Lempka, Passmore, et al., 1968; refers to X ²Π_3/2 of the ion. A more recent paper Delwiche, Natalis, et al., 1972 gives 11.64₅ eV.

Strongly broadened by preionization; estimated lifetime against preionization 9.5E-15 s Terwilliger and Smith, 1975.

From R, P branches. Δν_ef = -0.04lJ(J+1).

In absorption the 1-0, 2-0, 3-0, 3-1, 4-0, 5-0, 6-0 bands have been studied Naude and Verleger, 1950, Thompson, Williams, et al., 1952, Plyler, 1960, Rank, Fink, et al., 1965, Bernage, Niay, et al., 1973; in emission 1-0, 2-1, 3-2, 4-3 Mould, Price, et al., 1960, James and Thibault, 1965. The constants in the table are from Rank, Fink, et al., 1965, those of James and Thibault, 1965, Bernage, Niay, et al., 1973 are very similar and of comparable accuracy. See also Ogilvie and Koo, 1976. Absolute intensities have been measured Babrov, 1964, Babrov, Shabott, et al., 1965, Rao and Lindquist, 1968, Gustafson and Rao, 1970 and the dipole moment function has been calculated; Urquhart, Clark, et al., 1972 give for H⁷⁹Br[D, ]: μ_el(r) = +0.788 + 0.315(r-r_e) + 0.575(r-r_e)²; see also Jacobi, 1967, Tipping and Herman, 1970, Rao, 1971.

References

Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering data, Constants of diatomic molecules, Notes

Cox, Wagman, et al., 1984
Cox, J.D.; Wagman, D.D.; Medvedev, V.A., CODATA Key Values for Thermodynamics, Hemisphere Publishing Corp., New York, 1984, 1. [all data]

Chase, 1998
Chase, M.W., Jr., NIST-JANAF Themochemical Tables, Fourth Edition, J. Phys. Chem. Ref. Data, Monograph 9, 1998, 1-1951. [all data]

Caldwell and Kebarle, 1985
Caldwell, G.; Kebarle, P., The hydrogen bond energies of the bihalide ions XHX- and YHX-, Can. J. Chem., 1985, 63, 1399. [all data]

Davidson, Fehsenfeld, et al., 1977
Davidson, J.A.; Fehsenfeld, F.C.; Howard, C.J., The heats of formation of NO₃- and NO₃- association complexes with HNO₃ and HBr, Int. J. Chem. Kinet., 1977, 9, 17. [all data]

Blondel, Cacciani, et al., 1989
Blondel, C.; Cacciani, P.; Delsart, C.; Trainham, R., High Resolution Determination of the Electron Affinity of Fluorine and Bromine using Crossed Ion and Laser Beams, Phys. Rev. A, 1989, 40, 7, 3698, https://doi.org/10.1103/PhysRevA.40.3698 . [all data]

Taft and Bordwell, 1988
Taft, R.W.; Bordwell, F.G., Structural and Solvent Effects Evaluated from Acidities Measured in Dimethyl Sulfoxide and in the Gas Phase, Acc. Chem. Res., 1988, 21, 12, 463, https://doi.org/10.1021/ar00156a005 . [all data]

Check, Faust, et al., 2001
Check, C.E.; Faust, T.O.; Bailey, J.M.; Wright, B.J.; Gilbert, T.M.; Sunderlin, L.S., Addition of Polarization and Diffuse Functions to the LANL2DZ Basis Set for P-Block Elements, J. Phys. Chem. A,, 2001, 105, 34, 8111, https://doi.org/10.1021/jp011945l . [all data]

Nolan, López de la Vega, et al., 1986
Nolan, S.P.; López de la Vega, R.; Hoff, C.D., J. Organometal. Chem., 1986, 315, 187. [all data]

Lacher, Kianpour, et al., 1957
Lacher, J.R.; Kianpour, A.; Park, J.D., Reaction heats of organic halogen compounds. X. Vapor phase heats of hydrobromination of cyclopropane and propylene, J. Phys. Chem., 1957, 61, 1124-1125. [all data]

Lacher, Lea, et al., 1950
Lacher, J.R.; Lea, K.R.; Walden, C.H.; Olson, G.G.; Park, J.D., Reaction heats of organic fluorine compounds. III. The vapor phase heats of hydrobromination of some simple fluoroolefins, J. Am. Chem. Soc., 1950, 72, 3231-3234. [all data]

Lacher, Walden, et al., 1950
Lacher, J.R.; Walden, C.H.; Lea, K.R.; Park, J.D., Vapor phase heats of hydrobromination of cyclopropane and propylene, J. Am. Chem. Soc., 1950, 72, 331-333. [all data]

Cox and Pilcher, 1970
Cox, J.D.; Pilcher, G., Thermochemistry of Organic and Organometallic Compounds, Academic Press, New York, 1970, 1-636. [all data]

Holm, 1981
Holm, T., J. Chem. Soc., Perkin Trans. II, 1981, 464.. [all data]

Pedley, 1994
Pedley, J.B., Thermodynamic Data and Structures of Organic Compounds; Thermodynamics Research Center Data Series, Vol I, Thermodynamics Research Center, College Station, 1994. [all data]

Howard and Skinner, 1966
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Notes

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Symbols used in this document:

IE (evaluated)	Recommended ionization energy
S°_{gas,1 bar}	Entropy of gas at standard conditions (1 bar)
T	Temperature
Δ_fH°_gas	Enthalpy of formation of gas at standard conditions
Δ_rG°	Free energy of reaction at standard conditions
Δ_rH°	Enthalpy of reaction at standard conditions
Δ_rS°	Entropy of reaction at standard conditions

Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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