Hydrogen

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Phase change data

Go To: Top, Gas phase ion energetics data, Mass spectrum (electron ionization), 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

Quantity Value Units Method Reference Comment
Ttriple0.KN/ARoder, Childs, et al., 1973TRC
Ttriple13.95KN/AClusius and Weigand, 1940Uncertainty assigned by TRC = 0.06 K; see property X for dP/dT for c-l equil.; TRC
Ttriple13.96KN/AHenning and Otto, 1936Uncertainty assigned by TRC = 0.05 K; temperature measured with He gas thermometer; TRC
Quantity Value Units Method Reference Comment
Ptriple0.barN/ARoder, Childs, et al., 1973TRC
Ptriple0.0721barN/AHenning and Otto, 1936Uncertainty assigned by TRC = 0.0004 bar; TRC
Quantity Value Units Method Reference Comment
Tc33.18KN/AOnnes, Crommelin, et al., 1917Uncertainty assigned by TRC = 0.2 K; derived from P-V-T measurements; TRC
Quantity Value Units Method Reference Comment
Pc13.00barN/AOnnes, Crommelin, et al., 1917Uncertainty assigned by TRC = 0.0119 bar; derived from vapor pressure extrapolated to Tc; TRC
Quantity Value Units Method Reference Comment
ρc15.4mol/lN/AOnnes, Crommelin, et al., 1917Uncertainty assigned by TRC = 2. mol/l; by extrapolation of rectilinear diameter to Tc; TRC

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
21.01 to 32.273.5431499.3957.726van Itterbeek, Verbeke, et al., 1964Coefficents 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:


Gas phase ion energetics data

Go To: Top, Phase change data, Mass spectrum (electron ionization), References, Notes

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

Mass spectrum (electron ionization)

Go To: Top, Phase change data, Gas phase ion energetics 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: NIST Mass Spectrometry Data Center, William E. Wallace, director

Spectrum

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Mass spectrum
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Additional Data

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Owner NIST Mass Spectrometry Data Center
Collection (C) 2014 copyright by the U.S. Secretary of Commerce
on behalf of the United States of America. All rights reserved.
Origin American Petroleum Institute Research Project 44
NIST MS number 245692

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References

Go To: Top, Phase change data, Gas phase ion energetics data, Mass spectrum (electron ionization), Notes

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

Roder, Childs, et al., 1973
Roder, H.M.; Childs, G.E.; McCarty, R.D.; Angerhofer, P.E., Survey of the Prop. of the Hydrogen Isotopes Below Their Critical Temp, Natl. Bur. Stand. (U. S.), 1973. [all data]

Clusius and Weigand, 1940
Clusius, K.; Weigand, K., Melting Curves of the Gases A, Kr, Xe, CH4, CH3D, CD4, C2H4, C2H6, COS, and PH3 to 200 Atmospheres Pressure. The Chane of Volume on Melting, Z. Phys. Chem., Abt. B, 1940, 46, 1-37. [all data]

Henning and Otto, 1936
Henning, F.; Otto, J., Vapor pressure curves and triple points in the temperature region from 14 to 90 k, Phys. Z., 1936, 37, 633-8. [all data]

Onnes, Crommelin, et al., 1917
Onnes, H.K.; Crommelin, C.-A.; Cath, P.G., Isothermals of di-atomic substances and their binary mixtures. XIX. A preliminary determination of the critical point of hydrogen., Proc. K. Ned. Akad. Wet., 1917, 20, 178-184. [all data]

van Itterbeek, Verbeke, et al., 1964
van Itterbeek, A.; Verbeke, O.; Theewes, F.; Staes, K.; de Boelpaep, J., The Difference in Vapour Pressure Between Normal and Equilibrium Hydrogen. Vapour Pressure of Normal Hydrogen Between 20 ºK and 32 ºK, Physica (Amsterdam), 1964, 30, 6, 1238-1244, https://doi.org/10.1016/0031-8914(64)90114-4 . [all data]

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]


Notes

Go To: Top, Phase change data, Gas phase ion energetics data, Mass spectrum (electron ionization), References