Hydrogen iodide

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Gas phase thermochemistry data

Go To: Top, Phase change data, Reaction thermochemistry data, Henry's Law data, Constants of diatomic molecules, References, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Quantity Value Units Method Reference Comment
Δfgas26.50 ± 0.10kJ/molReviewCox, Wagman, et al., 1984CODATA Review value
Δfgas26.36kJ/molReviewChase, 1998Data last reviewed in September, 1961
Quantity Value Units Method Reference Comment
gas,1 bar206.59J/mol*KReviewChase, 1998Data last reviewed in September, 1961

Gas Phase Heat Capacity (Shomate Equation)

Cp° = 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
    Cp = heat capacity (J/mol*K)
    H° = standard enthalpy (kJ/mol)
    S° = standard entropy (J/mol*K)
    t = temperature (K) / 1000.

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Temperature (K) 298. to 1400.1400. to 6000.
A 26.0454035.44358
B 4.6896781.414708
C 4.911765-0.182088
D -2.6543970.011768
E 0.121419-4.054561
F 18.754997.919099
G 237.2018240.1097
H 26.3590326.35903
ReferenceChase, 1998Chase, 1998
Comment Data last reviewed in September, 1961 Data last reviewed in September, 1961

Phase change data

Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Henry's Law data, Constants of diatomic molecules, References, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled as indicated in comments:
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
AC - William E. Acree, Jr., James S. Chickos

Quantity Value Units Method Reference Comment
Tfus222.15KN/ABeckmann and Waentig, 1910Uncertainty assigned by TRC = 1.5 K; TRC

Enthalpy of vaporization

ΔvapH (kJ/mol) Temperature (K) Method Reference Comment
19.8238.CGiauque and Wiebe, 1929AC

Antoine Equation Parameters

log10(P) = A − (B / (T + C))
    P = vapor pressure (bar)
    T = temperature (K)

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Temperature (K) A B C Reference Comment
149.8 to 238.14.26854939.994-18.012Stull, 1947Coefficents calculated by NIST from author's data.

In addition to the Thermodynamics Research Center (TRC) data available from this site, much more physical and chemical property data is available from the following TRC products:


Reaction thermochemistry data

Go To: Top, Gas phase thermochemistry data, Phase change data, Henry's Law data, Constants of diatomic molecules, References, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

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

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.

Individual Reactions

Iodide + Hydrogen iodide = (Iodide • Hydrogen iodide)

By formula: I- + HI = (I- • HI)

Bond type: Hydrogen bond (negative ion to hydride)

Quantity Value Units Method Reference Comment
Δr71.1 ± 8.4kJ/molTDEqCaldwell and Kebarle, 1985gas phase; B,M
Quantity Value Units Method Reference Comment
Δr102.J/mol*KPHPMSCaldwell and Kebarle, 1985gas phase; switching reaction(I-)SO2; M
Quantity Value Units Method Reference Comment
Δr41. ± 11.kJ/molTDEqCaldwell and Kebarle, 1985gas phase; B

Free energy of reaction

ΔrG° (kJ/mol) T (K) Method Reference Comment
41.300.PHPMSCaldwell and Kebarle, 1985gas phase; switching reaction(I-)SO2; M

Iodide + Hydrogen cation = Hydrogen iodide

By formula: I- + H+ = HI

Quantity Value Units Method Reference Comment
Δr1315.24 ± 0.084kJ/molD-EAPelaez, Blondel, et al., 2009gas phase; Given: 3.0590463(38) eV; B
Δr1312.1kJ/molN/ACheck, Faust, et al., 2001gas phase; Fe(CO)2-(q); ; ΔS(EA)=5.0; B
Quantity Value Units Method Reference Comment
Δr1294.03 ± 0.25kJ/molH-TSPelaez, Blondel, et al., 2009gas phase; Given: 3.0590463(38) eV; B
Δr1290.8kJ/molN/ACheck, Faust, et al., 2001gas phase; Fe(CO)2-(q); ; ΔS(EA)=5.0; B

Hydrogen iodide + 1-Propene, 3-iodo- = Propene + Iodine

By formula: HI + C3H5I = C3H6 + I2

Quantity Value Units Method Reference Comment
Δr-33.3 ± 1.4kJ/molEqkRodgers, Golden, et al., 1966gas phase; ALS
Δr-39.7 ± 4.2kJ/molEqkRodgers, Golden, et al., 1966gas phase; Reanalyzed by Cox and Pilcher, 1970, Original value = -34.9 ± 0.96 kJ/mol; At 527 K; ALS

Hydrogen iodide + Methane, iodo- = Methane + Iodine

By formula: HI + CH3I = CH4 + I2

Quantity Value Units Method Reference Comment
Δr-52.55 ± 0.54kJ/molEqkGolden, Walsh, et al., 1965gas phase; ALS
Δr-53.0 ± 0.2kJ/molEqkGoy and Pritchard, 1965gas phase; ALS
Δr-46.2 ± 5.6kJ/molCmNichol and Ubbelohde, 1952gas phase; ALS

Hydromanganese pentacarbonyl (l) + Iodine (cr) = Hydrogen iodide (g) + Manganese, pentacarbonyliodo- (cr)

By formula: C5HMnO5 (l) + I2 (cr) = HI (g) + C5IMnO5 (cr)

Quantity Value Units Method Reference Comment
Δr-108. ± 8.kJ/molRSCConnor, Zafarani-Moattar, et al., 1982The reaction enthalpy relies on -25. ± 5. kJ/mol for the enthalpy of solution of HI(g) in benzene Connor, Zafarani-Moattar, et al., 1982.; MS

Acetyl iodide + Water = Hydrogen iodide + Acetic acid

By formula: C2H3IO + H2O = HI + C2H4O2

Quantity Value Units Method Reference Comment
Δr-93.97kJ/molCmDevore and O'Neal, 1969liquid phase; Heat of hydrolysis; ALS
Δr-90.33kJ/molCmCarson and Skinner, 1949liquid phase; Heat of hydrolysis; ALS

tert-Butyl iodide = Hydrogen iodide + 1-Propene, 2-methyl-

By formula: C4H9I = HI + C4H8

Quantity Value Units Method Reference Comment
Δr-81. ± 2.kJ/molEqkBenson and Amano, 1962gas phase; ALS
Δr-80.1 ± 4.2kJ/molEqkJones and Ogg, 1937gas phase; At 408-464 K; ALS

Hydrogen iodide + Cyclohexane, iodo- = Cyclohexane + Iodine

By formula: HI + C6H11I = C6H12 + I2

Quantity Value Units Method Reference Comment
Δr-32.6 ± 8.4kJ/molCmBrennan and Ubbelohde, 1956gas phase; Reanalyzed by Cox and Pilcher, 1970, Original value = -28. ± 4.2 kJ/mol; ALS

Ethane, 1,1,1-trifluoro- + Iodine = Hydrogen iodide + 1,1,1-Trifluoro-2-iodoethane

By formula: C2H3F3 + I2 = HI + C2H2F3I

Quantity Value Units Method Reference Comment
Δr-64. ± 2.kJ/molEqkWu and Rodgers, 1974gas phase; Heat of formation Unpublished results by B.J. Zwolinski; ALS

Benzenamine, 4-methoxy- + Benzoyl iodide = Hydrogen iodide + p-Benzanisidide

By formula: C7H9NO + C7H5IO = HI + C14H13NO2

Quantity Value Units Method Reference Comment
Δr-185. ± 2.kJ/molCacKiselev, Khuzyasheva, et al., 1979liquid phase; solvent: Benzene; ALS

p-Aminotoluene + Benzoyl iodide = Hydrogen iodide + Benzamide, N-(4-methylphenyl)-

By formula: C7H9N + C7H5IO = HI + C14H13NO

Quantity Value Units Method Reference Comment
Δr-168. ± 2.kJ/molCacKiselev, Khuzyasheva, et al., 1979liquid phase; solvent: Benzene; ALS

Benzoyl iodide + Aniline = Hydrogen iodide + Benzamide, N-phenyl-

By formula: C7H5IO + C6H7N = HI + C13H11NO

Quantity Value Units Method Reference Comment
Δr-166. ± 2.kJ/molCacKiselev, Khuzyasheva, et al., 1979liquid phase; solvent: Benzene; ALS

Tungsten, tricarbonyl(η5-2,4-cyclopentadien-1-yl)hydro- (cr) + Iodine (solution) = Hydrogen iodide (solution) + C8H5IO3W (solution)

By formula: C8H6O3W (cr) + I2 (solution) = HI (solution) + C8H5IO3W (solution)

Quantity Value Units Method Reference Comment
Δr-67.4 ± 3.8kJ/molRSCLandrum and Hoff, 1985solvent: Dichloromethane; MS

C8H6MoO3 (cr) + Iodine (solution) = C8H5IMoO3 (solution) + Hydrogen iodide (solution)

By formula: C8H6MoO3 (cr) + I2 (solution) = C8H5IMoO3 (solution) + HI (solution)

Quantity Value Units Method Reference Comment
Δr-75.3 ± 2.5kJ/molRSCLandrum and Hoff, 1985solvent: Dichloromethane; MS

2Propyl mercaptan + Iodine = 2Hydrogen iodide + Disulfide, dipropyl

By formula: 2C3H8S + I2 = 2HI + C6H14S2

Quantity Value Units Method Reference Comment
Δr-124.9kJ/molCmSunner, 1955liquid phase; solvent: Ethanol/water(90/10); ALS

21-Pentanethiol + Iodine = 2Hydrogen iodide + Disulfide, dipentyl

By formula: 2C5H12S + I2 = 2HI + C10H22S2

Quantity Value Units Method Reference Comment
Δr-124.9kJ/molCmSunner, 1955liquid phase; solvent: Ethanol/water(90/10); ALS

1,4-Butanedithiol + Iodine = 2Hydrogen iodide + 1,2-Dithiane

By formula: C4H10S2 + I2 = 2HI + C4H8S2

Quantity Value Units Method Reference Comment
Δr-123.2kJ/molCmSunner, 1955liquid phase; solvent: Ethanol/water(90/10); ALS

Octanoic acid, 6,8-dimercapto- + Iodine = 2Hydrogen iodide + Thioctic acid

By formula: C8H16O2S2 + I2 = 2HI + C8H14O2S2

Quantity Value Units Method Reference Comment
Δr-109.6kJ/molCmSunner, 1955liquid phase; solvent: Ethanol/water(90/10); ALS

1,3-Propanedithiol + Iodine = 2Hydrogen iodide + 1,2-Dithiolane

By formula: C3H8S2 + I2 = 2HI + C3H6S2

Quantity Value Units Method Reference Comment
Δr-107.7kJ/molCmSunner, 1955liquid phase; solvent: Ethanol/water(90/10); ALS

Hydrogen iodide + Benzene, (iodomethyl)- = Toluene + Iodine

By formula: HI + C7H7I = C7H8 + I2

Quantity Value Units Method Reference Comment
Δr-33. ± 4.6kJ/molCmGraham, Nichol, et al., 1955liquid phase; solvent: p-Xylene; ALS

1-Propene, 3-iodo- + Water = Hydrogen iodide + 2-Propen-1-ol

By formula: C3H5I + H2O = HI + C3H6O

Quantity Value Units Method Reference Comment
Δr-8.79kJ/molCmGellner and Skinner, 1949liquid phase; Heat of hydrolysis; ALS

Benzene, (iodomethyl)- + Water = Hydrogen iodide + Benzyl alcohol

By formula: C7H7I + H2O = HI + C7H8O

Quantity Value Units Method Reference Comment
Δr-12.6kJ/molCmGellner and Skinner, 1949liquid phase; Heat of hydrolysis; ALS

Benzoyl iodide + Water = Hydrogen iodide + Benzoic acid

By formula: C7H5IO + H2O = HI + C7H6O2

Quantity Value Units Method Reference Comment
Δr-102.4kJ/molCmCarson, Pritchard, et al., 1950liquid phase; Heat of hydrolysis; ALS

C3H9ISn (l) + Water (l) = (Hydrogen iodide • 55Water) (solution) + C3H10OSn (cr)

By formula: C3H9ISn (l) + H2O (l) = (HI • 55H2O) (solution) + C3H10OSn (cr)

Quantity Value Units Method Reference Comment
Δr-17.6 ± 0.4kJ/molRSCBaldwin, Lappert, et al., 1972MS

Hydrogen iodide + Methylsulfenyliodide = Methanethiol + Iodine

By formula: HI + CH3IS = CH4S + I2

Quantity Value Units Method Reference Comment
Δr-12.0 ± 2.3kJ/molEqkShum and Benson, 1983gas phase; ALS

Acetone + Iodine = Hydrogen iodide + 1-iodoacetone

By formula: C3H6O + I2 = HI + C3H5IO

Quantity Value Units Method Reference Comment
Δr50.6 ± 5.0kJ/molEqkSolly, Golden, et al., 1970gas phase; ALS

Acetaldehyde + Iodine = Hydrogen iodide + Acetyl iodide

By formula: C2H4O + I2 = HI + C2H3IO

Quantity Value Units Method Reference Comment
Δr3. ± 2.kJ/molEqkWalsh and Benson, 1966gas phase; ALS

Hydrogen iodide + p-Iodoanisole = Anisole + Iodine

By formula: HI + C7H7IO = C7H8O + I2

Quantity Value Units Method Reference Comment
Δr-29. ± 5.0kJ/molCmBrennan and Ubbelohde, 1956gas phase; ALS

Hydrogen iodide + Iodomethyl methyl sulfide = Dimethyl sulfide + Iodine

By formula: HI + C2H5IS = C2H6S + I2

Quantity Value Units Method Reference Comment
Δr-28. ± 4.6kJ/molKinShum and Benson, 1985gas phase; ALS

C10H12W (cr) + 2Iodine (cr) = C10H10I2W (cr) + 2Hydrogen iodide (g)

By formula: C10H12W (cr) + 2I2 (cr) = C10H10I2W (cr) + 2HI (g)

Quantity Value Units Method Reference Comment
Δr-104.3 ± 5.5kJ/molRSCCalado, Dias, et al., 1979MS

Hydrogen iodide + Benzoyl iodide = Benzaldehyde + Iodine

By formula: HI + C7H5IO = C7H6O + I2

Quantity Value Units Method Reference Comment
Δr-13. ± 4.2kJ/molEqkSolly and Benson, 1971gas phase; ALS

C10H11ClZr (cr) + Iodine (cr) = C10H10ClIZr (cr) + Hydrogen iodide (g)

By formula: C10H11ClZr (cr) + I2 (cr) = C10H10ClIZr (cr) + HI (g)

Quantity Value Units Method Reference Comment
Δr-78.1 ± 2.4kJ/molRSCDiogo, Simoni, et al., 1993MS

C10H12Mo (cr) + 2Iodine (cr) = C10H10I2Mo (cr) + 2Hydrogen iodide (g)

By formula: C10H12Mo (cr) + 2I2 (cr) = C10H10I2Mo (cr) + 2HI (g)

Quantity Value Units Method Reference Comment
Δr-87.8 ± 5.1kJ/molRSCCalado, Dias, et al., 1979MS

Ethane, 1,1-difluoro- + Iodine = Hydrogen iodide + 1-Bromo-1,1-difluoroethane

By formula: C2H4F2 + I2 = HI + C2H3BrF2

Quantity Value Units Method Reference Comment
Δr51.0 ± 0.8kJ/molEqkPickard and Rodgers, 1977gas phase; ALS

Benzaldehyde + Iodine = Hydrogen iodide + Benzoyl iodide

By formula: C7H6O + I2 = HI + C7H5IO

Quantity Value Units Method Reference Comment
Δr13. ± 4.2kJ/molEqkSolly and Benson, 1971gas phase; ALS

Hydrogen iodide + Benzene, iodo- = Benzene + Iodine

By formula: HI + C6H5I = C6H6 + I2

Quantity Value Units Method Reference Comment
Δr-22. ± 5.9kJ/molCmGraham, Nichol, et al., 1955gas phase; ALS

C10H11IW (cr) + Iodine (cr) = C10H10I2W (cr) + Hydrogen iodide (g)

By formula: C10H11IW (cr) + I2 (cr) = C10H10I2W (cr) + HI (g)

Quantity Value Units Method Reference Comment
Δr-84.6 ± 4.1kJ/molRSCCalhorda, Dias, et al., 1987MS

Iodine atom (g) + Germane (g) = Hydrogen iodide (g) + Germyl radical (g)

By formula: I (g) + H4Ge (g) = HI (g) + H3Ge (g)

Quantity Value Units Method Reference Comment
Δr47.0 ± 4.1kJ/molKinGNoble and Walsh, 1983MS

Cyclopentane + Iodine = 2Hydrogen iodide + Cyclopentene

By formula: C5H10 + I2 = 2HI + C5H8

Quantity Value Units Method Reference Comment
Δr102.1kJ/molEqkFuruyama, Golden, et al., 1970gas phase; ALS

Hydrogen iodide + 3-Iodo-2-butanone = Iodine + 2-Butanone

By formula: HI + C4H7IO = I2 + C4H8O

Quantity Value Units Method Reference Comment
Δr-42.7kJ/molKinSolly, Golden, et al., 1970, 2gas phase; ALS

2Hydrogen iodide + 1,3-Cyclopentadiene = Cyclopentene + Iodine

By formula: 2HI + C5H6 = C5H8 + I2

Quantity Value Units Method Reference Comment
Δr-89.5kJ/molEqkFuruyama, Golden, et al., 1970gas phase; ALS

Hydrogen iodide + Propene = Propane, 2-iodo-

By formula: HI + C3H6 = C3H7I

Quantity Value Units Method Reference Comment
Δr-86.27kJ/molEqkFuruyama, Golden, et al., 1969gas phase; ALS

Iodine atom (g) + C3H10Ge (g) = C3H9Ge (g) + Hydrogen iodide (g)

By formula: I (g) + C3H10Ge (g) = C3H9Ge (g) + HI (g)

Quantity Value Units Method Reference Comment
Δr42.0 ± 1.8kJ/molKinGDoncaster and Walsh, 1979MS

Henry's Law data

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

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled by: Rolf Sander

Henry's Law constant (water solution)

kH(T) = H exp(d(ln(kH))/d(1/T) ((1/T) - 1/(298.15 K)))
H = Henry's law constant for solubility in water at 298.15 K (mol/(kg*bar))
d(ln(kH))/d(1/T) = Temperature dependence constant (K)

H (mol/(kg*bar)) d(ln(kH))/d(1/T) (K) Method Reference Comment
2.5×10+9/KA9800.TN/AFor strong acids, the solubility is often expressed as kH = ([H+] * [A-]) / p(HA). To obtain the physical solubility of HA, the value has to be divided by the acidity constant KA. missing citation corrects erroneous data from missing citation.
2.2×10+9/KA9800.TN/A 

Constants of diatomic molecules

Go To: Top, Gas phase thermochemistry data, Phase change data, Reaction thermochemistry data, Henry's Law data, References, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

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

Data collected through September, 1976

Symbols used in the table of constants
SymbolMeaning
State electronic state and / or symmetry symbol
Te minimum electronic energy (cm-1)
ωe vibrational constant – first term (cm-1)
ωexe vibrational constant – second term (cm-1)
ωeye vibrational constant – third term (cm-1)
Be rotational constant in equilibrium position (cm-1)
αe rotational constant – first term (cm-1)
γe rotation-vibration interaction constant (cm-1)
De centrifugal distortion constant (cm-1)
βe rotational constant – first term, centrifugal force (cm-1)
re internuclear distance (Å)
Trans. observed transition(s) corresponding to electronic state
ν00 position of 0-0 band (units noted in table)
Diatomic constants for H127I
StateTeωeωexeωeyeBeαeγeDeβereTrans.ν00
L [100640] 1          L ← X 99500
Terwilliger and Smith, 1975
H (1) [75435] 2          H ← X 74290
missing citation; missing citation
F 1Δ [71372.8]    [6.335] 3   [2.3E-4] 3  [1.631] F ← X R 70228.2 Z
missing citation
f1 3Δ1 [70831.5]    [6.015] 4     [1.674] f1 ← X R 69686.9 Z
missing citation
StateTeωeωexeωeyeBeαeγeDeβereTrans.ν00
D 1Π [70389.0]    [6.198] 5   [2.1E-4] 5  [1.649] D ← X R 69244.4 Z
missing citation
d0 3Π0 [70302.4]    [6.117] 6   [2.1E-4] 6  [1.660] d0 ← X R 69157.8 6 Z
missing citation
7           
Ginter, Tilford, et al., 1975
G 1 [70136.4]    [6.406] 8   [3.2E-4] 8  [1.622] G ← X R 68991.8 Z
missing citation; missing citation
StateTeωeωexeωeyeBeαeγeDeβereTrans.ν00
V 1Σ+     [2.84] 9   [2.0E-4] 9  [2.44] 9 V ← X R 68004.4 9 Z
missing citation
E 1Σ+ (66326) [1681.8] Z   [6.110] 10  [2.5E-4] 10  [1.6611] E ← X R 66022.6 Z
missing citation; missing citation
f2 3Δ2 [65838.6]    [6.757] 11   [12.3E-4] 11  [1.580] f2 ← X V 64694.0 Z
missing citation
f3 3Δ3 [65717.5]    [5.706] 12   [-8.3E-4] 12  [1.719] f3 ← X R 64572.9 Z
missing citation
StateTeωeωexeωeyeBeαeγeDeβereTrans.ν00
e 3Σ+ [65345] 13          e ← X 64200
missing citation
d1 3Π1 [65028] 14          d1 ← X 63883 HQ
missing citation
d2 3Π2 (63922) [2154.4] Z   [6.065] 15  1.7E-4  [1.6673] d2 ← X R 63854.9 Z
missing citation
C 1Π (62378) [2183] HQ 16         C ← X 62325 HQ
Price, 1938; Tilford, Ginter, et al., 1970
StateTeωeωexeωeyeBeαeγeDeβereTrans.ν00
b0 3Π0+ 60858.7 2314.7 17 Z 54.3 17  6.493 17 0.118 17    1.6114 b0 ← X 60857.9 Z
missing citation; missing citation
b0 3Π0- (60840) 18 2314.7 17 Z 54.3 17  6.493 17 0.118 17    1.6114 b0 ← X 60839 HQ
missing citation
b1 3Π1 (56783) [2200]   [6.427] 19     [1.6196] b1 ← X 56738.3 Z
Price, 1938; Tilford, Ginter, et al., 1970
b2 3Π2 (55874) [2207.4] Z   6.436 0.175    1.6185 b2 ← X 55833.1 Z
missing citation
StateTeωeωexeωeyeBeαeγeDeβereTrans.ν00
A (1Π) 20          A ← X 21 
Goodeve and Taylor, 1936; Datta and Kundu, 1941; Romand, 1949; Huebert and Martin, 1968; Ogilvie, 1971
20          a ← X 21 
Goodeve and Taylor, 1936; Datta and Kundu, 1941; Romand, 1949; Huebert and Martin, 1968; Ogilvie, 1971
(3Π0+) 20          A ← X 21 
Goodeve and Taylor, 1936; Datta and Kundu, 1941; Romand, 1949; Huebert and Martin, 1968; Ogilvie, 1971
(3Π1) 20          a ← X 21 
Goodeve and Taylor, 1936; Datta and Kundu, 1941; Romand, 1949; Huebert and Martin, 1968; Ogilvie, 1971
StateTeωeωexeωeyeBeαeγeDeβereTrans.ν00
X 1Σ+ 0 2309.014 Z 39.6435 22 -0.0200 [6.4263650] 23 24 0.16886 25 -0.00095 [2.069E-4] 23  1.60916 26  
Boyd and Thompson, 1952; Haeusler, Meyer, et al., 1964; Hurlock, Alexander, et al., 1971; Bernage, Niay, et al., 1974
          27  
Czerny, 1927; Palik, 1955; Cowan and Gordy, 1956; De Lucia, Helminger, et al., 1971
          28  
Cherlow, Hyatt, et al., 1975

Notes

1Broad absorption peak (width ~4500 cm-1). 31
2First member of a Rydberg series converging to X 2 Π1/2 (v=0) of HI+ (I.P. = 11.05 eV); fragments of additional series. 32
3Average B and D, B(2+) - B(2-)= -0.05.
4Average of B value, B(1+) - B(1-) = +0.240.
5Refers to the 1+ component; B(1-) ~ 6.25.
6Constants refer to the 0+ component; for 0- B0 = 6.091, v00 = 69149.5.
7Additional unclassified absorption bands between 68100 and 69000 cm-1.
8missing note
9Vibrational numbering uncertain; the numbers given refer to the lowest level observed in absorption for which v is probably fairly high. Several higher vibrational levels have been found; strong perturbations.
10B1 = 5.62, D1= 28E-4, perturbed at high J.
11Average B and D, B(2+) - B(2-) = -0.040.
12Average B and D, B(3+) - B(3-) = +0.018.
13Very diffuse feature.
14Diffuse feature.
15B1(3Π2)= -5.923.
16Diffuse, no rotational structure.
17From v=0, 1, 3 only; γre = -0.0317.
18Diffuse Q head only.
19(v=1 diffuse Q head)
20Continuous absorption starting at ~28000 with maximum at ~46000 cm-1.
21Photofragment spectroscopy at 37550 cm-1 Clear, Riley, et al., 1975 shows that the continuum is of composite nature; 36% of the absorption is due to 3Π0+ yielding H + I(2P1/2). Clear, Riley, et al., 1975 have analyzed the continuum in terms of three overlapping transitions 1Π, 3Π0+, 3Π1 ← X. A very weak continuum with maximum at 23500 cm-1 was reported by Datta and Kundu, 1941.
22weze = +0.01621, from the 1-0,...,4-0 vibrational-rotational bands Hurlock, Alexander, et al., 1971; very slightly different constants are given by Bernage, Niay, et al., 1974 who have measured the 5-0 and 6-0 bands.
23Microwave value De Lucia, Helminger, et al., 1971.
24Dunham potential coefficients Ogilvie and Koo, 1976.
25γe from Hurlock, Alexander, et al., 1971, see 22.
26Rot.-vib. sp. 34
27Rotation sp. 35 36
28Raman sp. 37
29From D00(H2), D00(I2), and ΔHf0(HI, from gaseous H2,I2).
30From photoionization studies by Watanabe, Nakayama, et al., 1962; refers to X 2Π3/2 of HI+. Lempka, Passmore, et al., 1968 give the same value, Frost, McDowell, et al., 1967 give 10.42 eV from the photoelectron spectrum.
31Diffuse on account of predissociation and preionization; presumably first member of a Rydberg series converging to A 2Σ+ of HI+ Terwilliger and Smith, 1975.
32Above the first ionization limit (X 2Π3/2) the members of the series are subject to preionization and are seen as photoionization peaks Tsai and Baer, 1974.
33Average B and D, B(1+) - B(1-) = +0.107.
34The 1-0,...,6-0 bands have been observed in absorption. Absolute intensities, dipole moment function Ameer and Beneschi, 1962, Benesch, 1963, Meyer, Haeusler, et al., 1965, Jacobi, 1967, Tipping and Forbes, 1971. The R branch of the fundamental is much stronger than the P branch on account of rotation-vibration interaction; for the overtones this effect is very small Benesch, 1963, Meyer, Haeusler, et al., 1965. The overall intensities decrease rather slowly in the series 1-0, 2-0, 3-0 Benesch, 1963, Meyer, Haeusler, et al., 1965. Line width, pressure broadening studied by Ameer and Beneschi, 1962, Meyer, Haeusler, et al., 1965.
35From the hfs of the microwave spectrum Van Dijk and Dymanus, 1968 derive nuclear quadrupole (I) and other hyperfine coupling constants; see also De Lucia, Helminger, et al., 1971. From the Stark effect in the hfs of the 1-0 transition van Dijk and Dymanus, 1970 obtain μel(v=0) = 0.4477.
36Absolute intensities Chamberlain and Gebbie, 1965.
37Vibrational Raman cross sections.

References

Go To: Top, Gas phase thermochemistry data, Phase change data, Reaction thermochemistry data, Henry's Law data, Constants of diatomic molecules, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

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]

Beckmann and Waentig, 1910
Beckmann, E.; Waentig, P., Cryoscopic Measurements at Low Temperatures, Z. Anorg. Chem., 1910, 67, 17. [all data]

Giauque and Wiebe, 1929
Giauque, W.F.; Wiebe, R., THE HEAT CAPACITY OF HYDROGEN IODIDE FROM 15°K. TO ITS BOILING POINT AND ITS HEAT OF VAPORIZATION. THE ENTROPY FROM SPECTROSCOPIC DATA, J. Am. Chem. Soc., 1929, 51, 5, 1441-1449, https://doi.org/10.1021/ja01380a019 . [all data]

Stull, 1947
Stull, Daniel R., Vapor Pressure of Pure Substances. Organic and Inorganic Compounds, Ind. Eng. Chem., 1947, 39, 4, 517-540, https://doi.org/10.1021/ie50448a022 . [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]

Pelaez, Blondel, et al., 2009
Pelaez, R.J.; Blondel, C.; Delsart, C.; Drag, C., Pulsed photodetachment microscopy and the electron affinity of iodine, J. Phys. B: Atom. Mol. Opt. Phys., 2009, 42, 12, 125001, https://doi.org/10.1088/0953-4075/42/12/125001 . [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]

Rodgers, Golden, et al., 1966
Rodgers, A.S.; Golden, D.M.; Benson, S.W., The thermochemistry of the gas phase equilibrium I2 + C3H6 = C3H5I + HI, J. Am. Chem. Soc., 1966, 88, 3194-3196. [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]

Golden, Walsh, et al., 1965
Golden, D.M.; Walsh, R.; Benson, S.W., The thermochemistry of the gas phase equilibrium I2 + CH4 «=» CH3I + HI and the heat of formation of the methyl radical, J. Am. Chem. Soc., 1965, 87, 4053-4057. [all data]

Goy and Pritchard, 1965
Goy, C.A.; Pritchard, H.O., Kinetics and thermodynamics of the reaction between iodine and methane and the heat of formation of methyl iodide, J. Phys. Chem., 1965, 69, 3040-3041. [all data]

Nichol and Ubbelohde, 1952
Nichol, R.J.; Ubbelohde, A.R., A thermochemical evaluation of bond strengths in some carbon compounds. part II. Bond strengths based on the reaction CH3I + HI = CH4 + I2, J. Am. Chem. Soc., 1952, 415-421. [all data]

Connor, Zafarani-Moattar, et al., 1982
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Devore and O'Neal, 1969
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Carson and Skinner, 1949
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Benson and Amano, 1962
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Jones and Ogg, 1937
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Brennan and Ubbelohde, 1956
Brennan, D.; Ubbelohde, A.R., A thermochemical evaluation of bond strengths in some carbon compounds. Part IV. Bond-strength differences based on the reaction: RI + HI = RH + I2, where R = p-methoxyphenyl and cyclohexyl, J. Chem. Soc., 1956, 3011-3016. [all data]

Wu and Rodgers, 1974
Wu, E.; Rodgers, A.S., Thermochemistry of gas-phase equilibrium CF3CH3 + I2 = CF3CH2I + HI. The carbon-hydrogen bond dissociation energy in 1,1,1-trifluoroethane and the heat of formation of the 2,2,2-trifluoroethyl radical, J. Phys. Chem., 1974, 78, 2315-2317. [all data]

Kiselev, Khuzyasheva, et al., 1979
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Landrum and Hoff, 1985
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Sunner, 1955
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Graham, Nichol, et al., 1955
Graham, W.S.; Nichol, R.J.; Ubbelohde, A.R., A thermochemical evaluation of bond strengths in some carbon compounds. Part III. Bond strengths based on the reactions: (a) Ph·CH2I + HI=Ph·CH3 + I2 and (b) PhI + HI=PhH + I2, J. Chem. Soc., 1955, 115-121. [all data]

Gellner and Skinner, 1949
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Carson, Pritchard, et al., 1950
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Baldwin, Lappert, et al., 1972
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Shum and Benson, 1983
Shum, L.G.S.; Benson, S.W., Thermochemnistry and kinetics of the reaction of methyl mercaptan with iodine, Int. J. Chem. Kinet., 1983, 15, 433-453. [all data]

Solly, Golden, et al., 1970
Solly, R.K.; Golden, D.M.; Benson, S.W., Thermochemical properties of iodoacetone. Intramolecular electrostatic interactions in polar molecules, J. Am. Chem. Soc., 1970, 92, 4653-4656. [all data]

Walsh and Benson, 1966
Walsh, R.; Benson, S.W., The heats of formation of acetyl iodide and the acetyl radical, J. Phys. Chem., 1966, 70, 3751-3753. [all data]

Shum and Benson, 1985
Shum, L.G.S.; Benson, S.W., Iodine catalyzed pyrolysis of dimethyl sulfide. Heats of formaton of CH3SCH2I, the CH3SCH2 radical, and the pibond energy in CH2S, Int. J. Chem. Kinet., 1985, 17, 277-292. [all data]

Calado, Dias, et al., 1979
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Solly and Benson, 1971
Solly, R.K.; Benson, S.W., Thermochemistry of the reaction of benzaldehyde with iodine. The enthalpy of formation of benzaldehyde and benzoyl iodide, J. Chem. Thermodyn., 1971, 3, 203-209. [all data]

Diogo, Simoni, et al., 1993
Diogo, H.P.; Simoni, J.A.; Minas da Piedade, M.E.; Dias, A.R.; Martinho Simões, J.A., J. Am. Chem. Soc., 1993, 115, 2764. [all data]

Pickard and Rodgers, 1977
Pickard, J.M.; Rodgers, A.S., The kinetics and thermochemistry of the reaction of 1,1-difluoroethane with iodine. The difluoromethylene-hydrogen bond dissociation energy in 1,1-difluoroethane and the heat of formation of 1,1-difluoroethyl, J. Am. Chem. Soc., 1977, 99, 691-694. [all data]

Calhorda, Dias, et al., 1987
Calhorda, M.J.; Dias, A.R.; Minas da Piedade M.E.; Salema, M.S.; Martinho Simões J.A., Organometallics, 1987, 6, 734. [all data]

Noble and Walsh, 1983
Noble, P.N.; Walsh, R., Kinetics of the gas phase reaction between iodine and monogermane and the bond dissociation energy D(H3Ge-H), Int. J. Chem. Kinet., 1983, 15, 547. [all data]

Furuyama, Golden, et al., 1970
Furuyama, S.; Golden, D.M.; Benson, S.W., Thermochemistry of cyclopentene and cyclopentadiene from studies of gas-phase equilibria, J. Chem. Thermodyn., 1970, 2, 161-169. [all data]

Solly, Golden, et al., 1970, 2
Solly, R.K.; Golden, D.M.; Benson, S.W., Kinetics and thermochemistry of the gas phase reaction of methyl ethyl ketone with iodine. II. The heat of formation and unimolecular decomposition of 2-iodo-3-butanone, Int. J. Chem. Kinet., 1970, 2, 393-407. [all data]

Furuyama, Golden, et al., 1969
Furuyama, S.; Golden, D.M.; Benson, S.W., Thermochemistry of the gas phase equilibria i-C3H7I = C3H6 + HI, n-C3H7I = i-C3H7I, and C3H6 + 2HI = C3H8 + I2, J. Chem. Thermodyn., 1969, 1, 363-375. [all data]

Doncaster and Walsh, 1979
Doncaster, A.M.; Walsh, R., J. Phys. Chem., 1979, 83, 578. [all data]

Terwilliger and Smith, 1975
Terwilliger, D.T.; Smith, A.L., Autoionization in diatomics: measured line shape parameters and predicted photoelectron spectra for some autoionizing states of the hydrogen halides, J. Chem. Phys., 1975, 63, 1008. [all data]

Ginter, Tilford, et al., 1975
Ginter, M.L.; Tilford, S.G.; Bass, A.M., Electronic spectra and structure of the hydrogen halides. States associated with the (σ2π3)cσ and (σ2π3)cπ configurations of HI and DI, J. Mol. Spectrosc., 1975, 57, 271. [all data]

Price, 1938
Price, W.C., The absorption spectra of the halogen acids in the vacuum ultra-violet, Proc. Roy. Soc. (London), 1938, A167, 216. [all data]

Tilford, Ginter, et al., 1970
Tilford, S.G.; Ginter, M.L.; Bass, A.M., Electronic spectra and structure of the hydrogen halides. The b3Πi and C1Π states of HI and DI, J. Mol. Spectrosc., 1970, 34, 327. [all data]

Goodeve and Taylor, 1936
Goodeve, C.F.; Taylor, A.W.C., The continuous absorption spectrum of hydrogen iodide, Proc. R. Soc. London A, 1936, 154, 181. [all data]

Datta and Kundu, 1941
Datta, S.; Kundu, D.N., The continuous absorption spectra of the hydrogen-halides. Part III - HI, Proc. Natl. Inst. Sci. India, 1941, 7, 311. [all data]

Romand, 1949
Romand, J., Absorption ultraviolette dans la region de Schumann etude de: ClH, BrH et lH gazeux, Ann. Phys. (Paris), 1949, 4, 527. [all data]

Huebert and Martin, 1968
Huebert, B.J.; Martin, R.M., Gas-phase far-ultraviolet absorption spectrum of hydrogen bromide and hydrogen iodide, J. Phys. Chem., 1968, 72, 3046. [all data]

Ogilvie, 1971
Ogilvie, J.F., Semi-experimental determination of a repulsive potential curve for hydrogen iodide, Trans. Faraday Soc., 1971, 67, 2205. [all data]

Boyd and Thompson, 1952
Boyd, D.R.J.; Thompson, H.W., The fundamental vibration band of hydrogen iodide, Spectrochim. Acta, 1952, 5, 308. [all data]

Haeusler, Meyer, et al., 1964
Haeusler, C.; Meyer, C.; Barchewitz, P., Constantes de vibration et de rotation de l'acide iodhydrique gazeux etude des bandes d'absorption v0-2 et v0-4, J. Phys. (Paris), 1964, 25, 961. [all data]

Hurlock, Alexander, et al., 1971
Hurlock, S.C.; Alexander, R.M.; Rao, K.N.; Dreska, N., Infrared bands of HI and DI, J. Mol. Spectrosc., 1971, 37, 373. [all data]

Bernage, Niay, et al., 1974
Bernage, P.; Niay, P.; Houdart, R., Notes des membres et correspondants et notes presentees ou transmises par leurs soins, C.R. Acad. Sci. Paris, Ser. B, 1974, 278, 235. [all data]

Czerny, 1927
Czerny, M., Die rotationsspektren der halogenwasserstoffe, Z. Phys., 1927, 44, 235. [all data]

Palik, 1955
Palik, E.D., The pure rotational spectra of DBr, HI, and DI in the spectral region between 45 and 170 microns, J. Chem. Phys., 1955, 23, 217. [all data]

Cowan and Gordy, 1956
Cowan, M.; Gordy, W., Further extension of microwave spectroscopy in the submillimeter wave region, Phys. Rev., 1956, 104, 551. [all data]

De Lucia, Helminger, et al., 1971
De Lucia, F.C.; Helminger, P.; Gordy, W., Submillimeter-wave spectra and equilibrium structures of the hydrogen halides, Phys. Rev. A: Gen. Phys., 1971, 3, 1849. [all data]

Cherlow, Hyatt, et al., 1975
Cherlow, J.M.; Hyatt, H.A.; Porto, S.P.S., Raman scattering in hydrogen halide gases, J. Chem. Phys., 1975, 63, 3996. [all data]

Clear, Riley, et al., 1975
Clear, R.D.; Riley, S.J.; Wilson, K.R., Energy partitioning and assignment of excited states in the ultraviolet photolysis of HI and DI, J. Chem. Phys., 1975, 63, 1340. [all data]

Ogilvie and Koo, 1976
Ogilvie, J.F.; Koo, D., Dunham potential energy coefficients of the hydrogen halides and carbon monoxide, J. Mol. Spectrosc., 1976, 61, 332-336. [all data]

Watanabe, Nakayama, et al., 1962
Watanabe, K.; Nakayama, T.; Mottl, J., Ionization potentials of some molecules, J. Quant. Spectry. Radiative Transfer, 1962, 2, 369. [all data]

Lempka, Passmore, et al., 1968
Lempka, H.J.; Passmore, T.R.; Price, W.C., The photoelectron spectra and ionized states of the halogen acids, Proc. Roy. Soc. (London), 1968, A304, 53. [all data]

Frost, McDowell, et al., 1967
Frost, D.C.; McDowell, C.A.; Vroom, D.A., Photoelectron spectra of the halogens and the hydrogen halides, J. Chem. Phys., 1967, 46, 4255. [all data]

Tsai and Baer, 1974
Tsai, B.P.; Baer, T., Analysis of autoionizing Rydberg states in HI and CH3I. Comments on Rydberg electron wavefunctions, J. Chem. Phys., 1974, 61, 2047. [all data]

Ameer and Beneschi, 1962
Ameer, G.; Beneschi, W., Line strengths and widths in hydrogen iodide, J. Chem. Phys., 1962, 37, 2699. [all data]

Benesch, 1963
Benesch, W., Simultaneous measurement of HI fundamental and overtone lines, J. Chem. Phys., 1963, 39, 1048. [all data]

Meyer, Haeusler, et al., 1965
Meyer, C.; Haeusler, C.; Barchewitz, P., Intensites et largeurs des raies de vibration-rotation de molecules diatomiques, J. Phys. (Paris), 1965, 26, 305. [all data]

Jacobi, 1967
Jacobi, N., Electrical anharmonicities of diatomic molecules, J. Mol. Spectrosc., 1967, 22, 76. [all data]

Tipping and Forbes, 1971
Tipping, R.H.; Forbes, A., Dipole moment function of HI, J. Mol. Spectrosc., 1971, 39, 65. [all data]

Van Dijk and Dymanus, 1968
Van Dijk, F.A.; Dymanus, A., Hyperfine structure of the rotational spectrum of HI in the submillimeter region, Chem. Phys. Lett., 1968, 2, 235. [all data]

van Dijk and Dymanus, 1970
van Dijk, F.A.; Dymanus, A., The electric dipole moment of HI and HBr, Chem. Phys. Lett., 1970, 5, 387. [all data]

Chamberlain and Gebbie, 1965
Chamberlain, J.E.; Gebbie, H.A., Sub-millimetre dispersion and rotational line strengths of the hydrogen halides, Nature (London), 1965, 208, 480. [all data]


Notes

Go To: Top, Gas phase thermochemistry data, Phase change data, Reaction thermochemistry data, Henry's Law data, Constants of diatomic molecules, References