Hydrogen iodide
- Formula: HI
- Molecular weight: 127.91241
- IUPAC Standard InChIKey: XMBWDFGMSWQBCA-UHFFFAOYSA-N
- CAS Registry Number: 10034-85-2
- Chemical structure:
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Gas phase thermochemistry data
Go To: Top, Phase change 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 |
---|---|---|---|---|---|
ΔfH°gas | 26.50 ± 0.10 | kJ/mol | Review | Cox, Wagman, et al., 1984 | CODATA Review value |
ΔfH°gas | 26.36 | kJ/mol | Review | Chase, 1998 | Data last reviewed in September, 1961 |
Quantity | Value | Units | Method | Reference | Comment |
S°gas,1 bar | 206.59 | J/mol*K | Review | Chase, 1998 | Data 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.
View plot Requires a JavaScript / HTML 5 canvas capable browser.
Temperature (K) | 298. to 1400. | 1400. to 6000. |
---|---|---|
A | 26.04540 | 35.44358 |
B | 4.689678 | 1.414708 |
C | 4.911765 | -0.182088 |
D | -2.654397 | 0.011768 |
E | 0.121419 | -4.054561 |
F | 18.75499 | 7.919099 |
G | 237.2018 | 240.1097 |
H | 26.35903 | 26.35903 |
Reference | Chase, 1998 | Chase, 1998 |
Comment | Data last reviewed in September, 1961 | Data last reviewed in September, 1961 |
Phase change data
Go To: Top, Gas phase 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 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 |
---|---|---|---|---|---|
Tfus | 222.15 | K | N/A | Beckmann and Waentig, 1910 | Uncertainty assigned by TRC = 1.5 K; TRC |
Enthalpy of vaporization
ΔvapH (kJ/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
19.8 | 238. | C | Giauque and Wiebe, 1929 | AC |
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 238.1 | 4.26854 | 939.994 | -18.012 | Stull, 1947 | Coefficents calculated by NIST from author's data. |
Constants of diatomic molecules
Go To: Top, Gas phase thermochemistry data, Phase change 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
Symbol | Meaning |
---|---|
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) |
State | Te | ωe | ωexe | ωeye | Be | αe | γe | De | βe | re | Trans. | 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 | ||||||||||||
State | Te | ωe | ωexe | ωeye | Be | αe | γe | De | βe | re | Trans. | 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 | ||||||||||||
State | Te | ωe | ωexe | ωeye | Be | αe | γe | De | βe | re | Trans. | 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 | ||||||||||||
State | Te | ωe | ωexe | ωeye | Be | αe | γe | De | βe | re | Trans. | 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 | ||||||||||||
State | Te | ωe | ωexe | ωeye | Be | αe | γe | De | βe | re | Trans. | 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 | ||||||||||||
State | Te | ωe | ωexe | ωeye | Be | αe | γe | De | βe | re | Trans. | 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 | ||||||||||||
State | Te | ωe | ωexe | ωeye | Be | αe | γe | De | βe | re | Trans. | 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
1 | Broad absorption peak (width ~4500 cm-1). 31 |
2 | First 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 |
3 | Average B and D, B(2+) - B(2-)= -0.05. |
4 | Average of B value, B(1+) - B(1-) = +0.240. |
5 | Refers to the 1+ component; B(1-) ~ 6.25. |
6 | Constants refer to the 0+ component; for 0- B0 = 6.091, v00 = 69149.5. |
7 | Additional unclassified absorption bands between 68100 and 69000 cm-1. |
8 | missing note |
9 | Vibrational 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. |
10 | B1 = 5.62, D1= 28E-4, perturbed at high J. |
11 | Average B and D, B(2+) - B(2-) = -0.040. |
12 | Average B and D, B(3+) - B(3-) = +0.018. |
13 | Very diffuse feature. |
14 | Diffuse feature. |
15 | B1(3Π2)= -5.923. |
16 | Diffuse, no rotational structure. |
17 | From v=0, 1, 3 only; γre = -0.0317. |
18 | Diffuse Q head only. |
19 | (v=1 diffuse Q head) |
20 | Continuous absorption starting at ~28000 with maximum at ~46000 cm-1. |
21 | Photofragment 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. |
22 | weze = +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. |
23 | Microwave value De Lucia, Helminger, et al., 1971. |
24 | Dunham potential coefficients Ogilvie and Koo, 1976. |
25 | γe from Hurlock, Alexander, et al., 1971, see 22. |
26 | Rot.-vib. sp. 34 |
27 | Rotation sp. 35 36 |
28 | Raman sp. 37 |
29 | From D00(H2), D00(I2), and ΔHf0(HI, from gaseous H2,I2). |
30 | From 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. |
31 | Diffuse on account of predissociation and preionization; presumably first member of a Rydberg series converging to A 2Σ+ of HI+ Terwilliger and Smith, 1975. |
32 | Above 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. |
33 | Average B and D, B(1+) - B(1-) = +0.107. |
34 | The 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. |
35 | From 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. |
36 | Absolute intensities Chamberlain and Gebbie, 1965. |
37 | Vibrational Raman cross sections. |
References
Go To: Top, Gas phase thermochemistry data, Phase change 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]
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, Constants of diatomic molecules, References
- Symbols used in this document:
S°gas Entropy of gas at standard conditions S°gas,1 bar Entropy of gas at standard conditions (1 bar) Tfus Fusion (melting) point ΔfH°gas Enthalpy of formation of gas at standard conditions ΔvapH Enthalpy of vaporization - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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