Iodine

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Gas phase thermochemistry data

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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
Δfgas62.42 ± 0.08kJ/molReviewCox, Wagman, et al., 1984CODATA Review value
Δfgas62.42kJ/molReviewChase, 1998Data last reviewed in June, 1982
Quantity Value Units Method Reference Comment
gas,1 bar260.687 ± 0.005J/mol*KReviewCox, Wagman, et al., 1984CODATA Review value
gas,1 bar260.69J/mol*KReviewChase, 1998Data last reviewed in June, 1982

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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View table.

Temperature (K) 457.666 to 2000.2000. to 6000.
A 37.7976376.73414
B 0.225453-4.045782
C -0.912556-1.848145
D 1.0349130.219044
E -0.083826-82.39384
F 50.86865-53.87151
G 305.9199281.2267
H 62.4211062.42110
ReferenceChase, 1998Chase, 1998
Comment Data last reviewed in June, 1982 Data last reviewed in June, 1982

Phase change data

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

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
311.9 to 456.3.364291039.159-146.589Stull, 1947Coefficents calculated by NIST from author's data.

Gas phase ion energetics data

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

Data evaluated as indicated in comments:
L - Sharon G. Lias

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

View reactions leading to I2+ (ion structure unspecified)

Quantity Value Units Method Reference Comment
IE (evaluated)9.3074 ± 0.0002eVN/AN/AL

Electron affinity determinations

EA (eV) Method Reference Comment
2.5240 ± 0.0050LPESZanni, Taylor, et al., 1997B
2.52 ± 0.10NBIEAuerbach, Baeda, et al., 1973B
2.42 ± 0.20EndoHughes, Lifschitz, et al., 1973B
2.58 ± 0.10EndoChupka, Berkowitz, et al., 1971B
2.60 ± 0.10EIAEDeCorpo and Franklin, 1971From CHI3; B
2.40 ± 0.10NBIEMoutinho, Aten, et al., 1971B
2.33004ECDAyala, Wentworth, et al., 1981Vertical Detachment Energy: 1.7 eV; B
1.722 ± 0.050NBIEHubers, Kleyn, et al., 1976Stated electron affinity is the Vertical Detachment Energy; B

Ionization energy determinations

IE (eV) Method Reference Comment
9.3074 ± 0.0002TECockett, Donovan, et al., 1996LL
9.3074 ± 0.0002TECockett, Goode, et al., 1995LL
9.33PECarlson, Gerard, et al., 1988LL
9.29 ± 0.05PIGrade and Rosinger, 1985LBLHLM
9.3 ± 0.2EIGrade and Rosinger, 1985LBLHLM
9.3 ± 0.2EIGrade and Rosinger, 1984LBLHLM
9.3 ± 0.2EIGrade, Rosinger, et al., 1984LBLHLM
9.3 ± 0.05EIHoareau, Cabaud, et al., 1981LLK
9.5EIPittermann and Weil, 1980LLK
9.311 ± 0.002PEHigginson, Lloyd, et al., 1973LLK
9.22 ± 0.01PEPotts and Price, 1971LLK
~9.37PIDibeler, Walker, et al., 1971LLK
9.3995 ± 0.0012SVenkateswarlu, 1970RDSH
9.331PIMyer and Samson, 1970RDSH
9.356PEKimura, Katsumata, et al., 1981Vertical value; LLK
9.34PECornford, Frost, et al., 1971Vertical value; LLK

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
I+8.8 ± 0.2I-EIGrade and Rosinger, 1985LBLHLM
I+11.94 ± 0.15IPIGrade and Rosinger, 1985LBLHLM
I+8.83 ± 0.07I-PIGrade and Rosinger, 1985LBLHLM
I+8.9 ± 0.2I-EIGrade and Rosinger, 1984LBLHLM
I+8.8 ± 0.2I-EIGrade, Rosinger, et al., 1984LBLHLM
I+13.0IEIPittermann and Weil, 1980LLK
I+8.922 ± 0.013I-PIMyer and Samson, 1970RDSH
I+8.95 ± 0.02I-PIMorrison, Hurzeler, et al., 1960RDSH
I+8.83 ± 0.02I-PIWatanabe, 1957RDSH

References

Go To: Top, Gas phase thermochemistry data, Phase change data, Gas phase ion energetics data, 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]

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]

Zanni, Taylor, et al., 1997
Zanni, M.T.; Taylor, T.R.; Greenblatt, J.; Soep, B.; Neumark, D.M., Characterization of the I2- Anion Ground State Using Conventional and Femtosecond Photoelectron Spectroscopy, J. Chem. Phys., 1997, 107, 19, 7613, https://doi.org/10.1063/1.475110 . [all data]

Auerbach, Baeda, et al., 1973
Auerbach, J.; Baeda, A.P.M.; Los, D.J., Fragmentation of Negative Ions Formed in Collisions of Alkali Atoms and Halogen Molecules, Physica, 1973, 64, 1, 134, https://doi.org/10.1016/0031-8914(73)90119-5 . [all data]

Hughes, Lifschitz, et al., 1973
Hughes, B.M.; Lifschitz, C.; Tiernan, T.O., Electron affinities from endothermic negative-ion charge-transfer reactions. III. NO, NO2, S2, CS2, Cl2, Br2, I2, and C2H, J. Chem. Phys., 1973, 59, 3162. [all data]

Chupka, Berkowitz, et al., 1971
Chupka, W.A.; Berkowitz, J.; Gutman, D., Electron Affinities of Halogen Diatomic Molecules as Determined by Endoergic Charge Exchange, J. Chem. Phys., 1971, 55, 6, 2724, https://doi.org/10.1063/1.1676487 . [all data]

DeCorpo and Franklin, 1971
DeCorpo, J.J.; Franklin, J.L., Electron affinities of the halogen molecules by dissociative electron attachment, J. Chem. Phys., 1971, 54, 1885. [all data]

Moutinho, Aten, et al., 1971
Moutinho, A.M.C.; Aten, J.A.; Los, J., Temperature dependence of the total cross section for chemi-ionization in ackali halide-galogen collisions, Physica, 1971, 53, 471. [all data]

Ayala, Wentworth, et al., 1981
Ayala, J.A.; Wentworth, W.E.; Chen, E.C.M., Electron attachment to halogens, J. Phys. Chem., 1981, 85, 768. [all data]

Hubers, Kleyn, et al., 1976
Hubers, M.M.; Kleyn, A.W.; Los, J., Ion pair formation in alkali-halogen collisions at high velocities, Chem. Phys., 1976, 17, 303. [all data]

Cockett, Donovan, et al., 1996
Cockett, M.C.R.; Donovan, R.J.; Lawley, K.P., Zero kinetic energy pulsed field ionization (ZEKE-PFI) spectroscopy of electronically and vibrationally excited states of I2+: The A 2Π3/2,u state and a new electronic state, the a 4σ-u state, J. Chem. Phys., 1996, 105, 3347. [all data]

Cockett, Goode, et al., 1995
Cockett, M.C.R.; Goode, J.G.; Lawley, K.P.; Donovan, R.J., Zero kinetic energy photoelectron spectroscopy of Rydberg excited molecular iodine, J. Chem. Phys., 1995, 102, 5226. [all data]

Carlson, Gerard, et al., 1988
Carlson, T.A.; Gerard, P.; Pullen, B.P.; Grimm, F.A., Autoionization from the ione-pair orbitals of molecules containing iodine, J. Chem. Phys., 1988, 89, 1464. [all data]

Grade and Rosinger, 1985
Grade, M.; Rosinger, W., Correlation of electronic structures and stabilities of gaseous FeI2, Fe2I2 and Fe2I4 molecules, solid [FeI2], and iodine adsorbed on [Fe], Surf. Sci., 1985, 156, 920. [all data]

Grade and Rosinger, 1984
Grade, M.; Rosinger, W., A mass spectrometric investigation of iron(II)-iodide, Ber. Bunsen-Ges. Phys. Chem., 1984, 88, 767. [all data]

Grade, Rosinger, et al., 1984
Grade, M.; Rosinger, W.; Dowben, P.A., Core and valence electron binding energies of FeI2 and stabilities of gas phase species, Ber. Bunsen-Ges. Phys. Chem., 1984, 88, 65. [all data]

Hoareau, Cabaud, et al., 1981
Hoareau, A.; Cabaud, B.; Melinon, P., Time-of-flight mass spectroscopy of supersonic beam of metallic vapours: Intensities and appearance potentials of Mx aggregates, Surf. Sci., 1981, 106, 195. [all data]

Pittermann and Weil, 1980
Pittermann, U.; Weil, K.G., Massenspektrometrische Untersuchungen an Silberhalogeniden V: Verdampfung von Silberiodid, Ber. Bunsen-Ges. Phys. Chem., 1980, 84, 542. [all data]

Higginson, Lloyd, et al., 1973
Higginson, B.R.; Lloyd, D.R.; Roberts, P.J., Variable temperature photoelectron spectroscopy. The adiabatic ionization potential of the iodine molecule, Chem. Phys. Lett., 1973, 19, 480. [all data]

Potts and Price, 1971
Potts, A.W.; Price, W.C., Photoelectron spectra of the halogens and mixed halides ICI and lBr, J. Chem. Soc. Faraday Trans., 1971, 67, 1242. [all data]

Dibeler, Walker, et al., 1971
Dibeler, V.H.; Walker, J.A.; McCulloh, K.E.; Rosenstock, H.M., Effect of hot bands on the ionization threshold of some diatomic halogen molecules, Intern. J. Mass Spectrom. Ion Phys., 1971, 7, 209. [all data]

Venkateswarlu, 1970
Venkateswarlu, P., Vacuum ultraviolet spectrum of the iodine molecule, Can. J. Phys., 1970, 48, 1055. [all data]

Myer and Samson, 1970
Myer, J.A.; Samson, J.A.R., Absorption cross section and photoionization yield of I2 between 1050 and 2200 A, J. Chem. Phys., 1970, 52, 716. [all data]

Kimura, Katsumata, et al., 1981
Kimura, K.; Katsumata, S.; Achiba, Y.; Yamazaki, T.; Iwata, S., Ionization energies, Ab initio assignments, and valence electronic structure for 200 molecules in Handbook of HeI Photoelectron Spectra of Fundamental Organic Compounds, Japan Scientific Soc. Press, Tokyo, 1981. [all data]

Cornford, Frost, et al., 1971
Cornford, A.B.; Frost, D.C.; McDowell, C.A.; Ragle, J.L.; Stenhouse, I.A., Photoelectron spectra of the halogens, J. Chem. Phys., 1971, 54, 2651. [all data]

Morrison, Hurzeler, et al., 1960
Morrison, J.D.; Hurzeler, H.; Inghram, M.G.; Stanton, H.E., Threshold law for the probability of excitation of molecules by photon impact. A study of the photoionization efficiencies of Br2, I2, HI, and CH3I, J. Chem. Phys., 1960, 33, 821. [all data]

Watanabe, 1957
Watanabe, K., Ionization potentials of some molecules, J. Chem. Phys., 1957, 26, 542. [all data]


Notes

Go To: Top, Gas phase thermochemistry data, Phase change data, Gas phase ion energetics data, References