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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:
HL - Edward P. Hunter and Sharon G. Lias
L - Sharon G. Lias

Data compiled as indicated in comments:
B - John E. Bartmess
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

View reactions leading to H2+ (ion structure unspecified)

Quantity Value Units Method Reference Comment
IE (evaluated)15.42593 ± 0.00005eVN/AN/AL
Quantity Value Units Method Reference Comment
Proton affinity (review)422.3kJ/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Gas basicity394.7kJ/molN/AHunter and Lias, 1998HL

Ionization energy determinations

IE (eV) Method Reference Comment
15.425927EVALShiner, Gilligan, et al., 1993T = 0K; LL
15.425930EVALShiner, Gilligan, et al., 1993T = 0K; LL
15.425932 ± 0.000002SMcCormack, Gilligan, et al., 1989T = 0K; LL
15.429558 ± 0.00001LSGlab and Hessler, 1987T = 0K; LBLHLM
15.433174 ± 0.00001LSGlab and Hessler, 1987T = 0K; LBLHLM
15.425942 ± 0.00001LSGlab and Hessler, 1987T = 0K; LBLHLM
15.425932SEyler, Short, et al., 1986T = 0K; LBLHLM
15.425929SEyler, Short, et al., 1986T = 0K; LBLHLM
15.425930 ± 0.000027N/AEyler, Short, et al., 1986LBLHLM
15.5 ± 1.0SFarber, Srivastava, et al., 1982LBLHLM
15.98PEKimura, Katsumata, et al., 1981LLK
15.43PEBieri, Schmelzer, et al., 1980LLK
15.42589EVALHuber and Herzberg, 1979LLK
16. ± 1.EIFarber and Srivastava, 1977LLK
15.4PIRabalais, Debies, et al., 1974LLK
15.43PELee and Rabalais, 1974LLK
15.42589 ± 0.00005SHerzberg and Jungen, 1972LLK
15.4256 ± 0.0001STakezawa, 1970RDSH
15.38186 ± 0.00031PEAsbrink, 1970RDSH
15.44 ± 0.01EILossing and Semeluk, 1969RDSH
15.4256SHerzberg, 1969RDSH
15.431 ± 0.022TEVillarejo, 1968RDSH
15.439 ± 0.015PECollin and Natalis, 1968RDSH
15.43CICermak, 1968RDSH
15.37 ± 0.05EIKerwin, Marmet, et al., 1963RDSH
15.4269 ± 0.0016SBeutler and Junger, 1936RDSH

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
H+18.078 ± 0.003HPIPECOWeitzel, Mahnert, et al., 1994T = 0K; LL
H+18.0 ± 0.2HEICrowe and McConkey, 1973LLK
H+17.28 ± 0.16H-EILocht and Momigny, 1971LLK
H+17.3H-EICurran, LaboratoriesRDSH

De-protonation reactions

Hydrogen anion + Hydrogen cation = Hydrogen

By formula: H- + H+ = H2

Quantity Value Units Method Reference Comment
Δr1675.3kJ/molN/AShiell, Hu, et al., 2000gas phase; Given: 139714.8±1 cm-1 at 0K, or 399.465±0.003 kcal/mol; B
Δr1675.3kJ/molN/APratt, McCormack, et al., 1992gas phase; 399.46±0.01 kcal/mol at 0K; 0.94 correction, Gurvich, Veyts, et al.; B
Δr1675.3kJ/molD-EALykke, Murray, et al., 1991gas phase; Reported: 6082.99±0.15 cm-1, or 0.754195(18) eV; B
Quantity Value Units Method Reference Comment
Δr1649.3 ± 0.42kJ/molH-TSShiell, Hu, et al., 2000gas phase; Given: 139714.8±1 cm-1 at 0K, or 399.465±0.003 kcal/mol; B
Δr1649.3kJ/molH-TSLykke, Murray, et al., 1991gas phase; Reported: 6082.99±0.15 cm-1, or 0.754195(18) eV; B


Go To: Top, 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.

Hunter and Lias, 1998
Hunter, E.P.; Lias, S.G., Evaluated Gas Phase Basicities and Proton Affinities of Molecules: An Update, J. Phys. Chem. Ref. Data, 1998, 27, 3, 413-656, https://doi.org/10.1063/1.556018 . [all data]

Shiner, Gilligan, et al., 1993
Shiner, D.; Gilligan, J.M.; Cook, B.M.; Lichten, W., H2, D2, and HD ionization potentials by accurate calibration of several iodine lines, Phys. Rev. A, 1993, 47, 4042. [all data]

McCormack, Gilligan, et al., 1989
McCormack, E.; Gilligan, J.M.; Cornaggia, C.; Eyler, E.E., Measurement of high Rydberg states and the ionization potential of H2, Phys. Rev. A, 1989, 39, 2260. [all data]

Glab and Hessler, 1987
Glab, W.L.; Hessler, J.P., Multiphoton excitation of high singlet np Rydberg states of molecular hydrogen: Spectroscopy and dynamics, Phys. Rev. A, 1987, 35, 2102. [all data]

Eyler, Short, et al., 1986
Eyler, E.E.; Short, R.C.; Pipkin, F.M., Precision spectroscopy of the nf triplet Rydberg states of H2 and determination of the triplet ionization potential, Phys. Rev. Lett., 1986, 56, 2602. [all data]

Farber, Srivastava, et al., 1982
Farber, M.; Srivastava, R.D.; Moyer, J.W., Mass spectrometric determination of the thermodynamics of potassium hydroxide and minor potassium-containing species required in magnetohydrodynamic power systems, J. Chem. Thermodyn., 1982, 14, 1103. [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]

Bieri, Schmelzer, et al., 1980
Bieri, G.; Schmelzer, A.; Asbrink, L.; Jonsson, M., Fluorine and the fluoroderivatives of acetylene and diacetylene studied by 30.4 nm He(II) photoelectron spectroscopy, Chem. Phys., 1980, 49, 213. [all data]

Huber and Herzberg, 1979
Huber, K.P.; Herzberg, G., Molecular Spectra and Molecular Structure. IV. Constants of Diatomic Molecules,, Van Nostrand Reinhold Co., 1979, ,1. [all data]

Farber and Srivastava, 1977
Farber, M.; Srivastava, R.D., Mass spectrometric determination of the heats of formation of the silane fluorides, Chem. Phys. Lett., 1977, 51, 307. [all data]

Rabalais, Debies, et al., 1974
Rabalais, J.W.; Debies, T.P.; Berkosky, J.L.; Huang, J.-T.J.; Ellison, F.O., Calculated photoionization cross sections relative experimental photoionization intensities for a selection of small molecules, J. Chem. Phys., 1974, 61, 516. [all data]

Lee and Rabalais, 1974
Lee, T.H.; Rabalais, J.W., Vibrational transition probabilities in photoelectron spectra, J. Chem. Phys., 1974, 61, 2747. [all data]

Herzberg and Jungen, 1972
Herzberg, G.; Jungen, Ch., Rydberg series and ionization potential of the H2 molecule, J. Mol. Spectrosc., 1972, 41, 425. [all data]

Takezawa, 1970
Takezawa, S., Absorption spectrum of H2 in the vacuum-uv region. II. Rydberg series converging to the first six vibrational levels of the H2+ ground state, J. Chem. Phys., 1970, 52, 5793. [all data]

Asbrink, 1970
Asbrink, L., The photoelectron spectrum of H2, Chem. Phys. Lett., 1970, 7, 549. [all data]

Lossing and Semeluk, 1969
Lossing, F.P.; Semeluk, G.P., Threshold ionization efficiency curves for monoenergetic electron impact on H2, D2, CH4 and CD4, Intern. J. Mass Spectrom. Ion Phys., 1969, 2, 408. [all data]

Herzberg, 1969
Herzberg, G., Dissociation energy and ionization potential of molecular hydrogen, Phys. Rev. Letters, 1969, 23, 1081. [all data]

Villarejo, 1968
Villarejo, D., Measurement of threshold electrons in the photoionization of H2 and D2, J. Chem. Phys., 1968, 48, 4014. [all data]

Collin and Natalis, 1968
Collin, J.E.; Natalis, P., Vibrational and electronic ionic states of nitric oxide. An accurate method for measuring ionization potentials by photoelectron spectroscopy, Intern. J. Mass Spectrom. Ion Phys., 1968, 1, 483. [all data]

Cermak, 1968
Cermak, V., Penning ionization electron spectroscopy. I. Determination of ionization potentials of polyatomic molecules, Collection Czech. Chem. Commun., 1968, 33, 2739. [all data]

Kerwin, Marmet, et al., 1963
Kerwin, L.; Marmet, P.; Clarke, E.M., Recent work with the electrostatic electron selector, Advan. Mass Spectrom., 1963, 2, 522. [all data]

Beutler and Junger, 1936
Beutler, H.; Junger, H.-O., Uber das Absorptionsspektrum des Wasserstoffs. III. Die Autoionisierung im Term 3pπ 1u des H2 und ihre Auswahlgesetze. Bestimmung der lonisierungsenergie des H2, Z. Physik, 1936, 100, 80. [all data]

Weitzel, Mahnert, et al., 1994
Weitzel, K.-M.; Mahnert, J.; Penno, M., ZEKE-PEPICO investigations of dissociation energies in ionic reactions, Chem. Phys. Lett., 1994, 224, 371. [all data]

Crowe and McConkey, 1973
Crowe, A.; McConkey, J.W., Dissociative ionization by electron impact. I. Protons from H2, J. Phys. B:, 1973, 6, 2088. [all data]

Locht and Momigny, 1971
Locht, R.; Momigny, J., Mass spectrometric study of ion-pair processes in diatomic molecules: H2, CO, NO and O2, Int. J. Mass Spectrom. Ion Phys., 1971, 7, 121. [all data]

Curran, Laboratories
Curran, R.K., Negative ion formation in various gases at pressures up to .5 mm of Hg, Scientific Paper 62-908-113-P7, Westinghouse Research, Laboratories, Pittsburgh, 1962. [all data]

Shiell, Hu, et al., 2000
Shiell, R.C.; Hu, X.K.; Hu, Q.C.J.; Hepburn, J.W., Threshold Ion-pair Production spectroscopy (TIPPS) of H2 and D2, Faraday Disc. Chem. Soc., 2000, 115, 331, https://doi.org/10.1039/a909428h . [all data]

Pratt, McCormack, et al., 1992
Pratt, S.T.; McCormack, E.F.; Dehmer, J.L.; Dehmer, P.M., Field-Induced Ion-Pair Formation in Molecular Hydrogen, Phys. Rev. Lett., 1992, 68, 5, 584, https://doi.org/10.1103/PhysRevLett.68.584 . [all data]

Gurvich, Veyts, et al.
Gurvich, L.V.; Veyts, I.V.; Alcock, C.B., Hemisphere Publishing, NY, 1989, V. 1 2, Thermodynamic Properties of Individual Substances, 4th Ed. [all data]

Lykke, Murray, et al., 1991
Lykke, K.R.; Murray, K.K.; Lineberger, W.C., Threshold Photodetachment of H-, Phys. Rev. A, 1991, 43, 11, 6104, https://doi.org/10.1103/PhysRevA.43.6104 . [all data]


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