Hydrogen atom
- Formula: H
- Molecular weight: 1.00794
- IUPAC Standard InChIKey: YZCKVEUIGOORGS-UHFFFAOYSA-N
- CAS Registry Number: 12385-13-6
- Chemical structure:
This structure is also available as a 2d Mol file - Isotopologues:
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Gas phase ion energetics data
Go To: Top, 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:
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
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron
View reactions leading to H+ (ion structure unspecified)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
IE (evaluated) | 13.59844 | eV | N/A | N/A | L |
Quantity | Value | Units | Method | Reference | Comment |
ΔfH°(+) ion | 1530. | kJ/mol | N/A | N/A | |
Quantity | Value | Units | Method | Reference | Comment |
ΔfH(+) ion,0K | 1528. | kJ/mol | N/A | N/A |
Electron affinity determinations
EA (eV) | Method | Reference | Comment |
---|---|---|---|
0.75497 | D-EA | Shiell, Hu, et al., 2000 | Given: 139714.8±1 cm-1 at 0K, or 399.465±0.003 kcal/mol; B |
0.754189 | LPES | Lykke, Murray, et al., 1991 | Reported: 6082.99±0.15 cm-1, or 0.754195(18) eV; B |
0.776 ± 0.020 | PD | Feldman, 1970 | B |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
13.59844 | EVAL | Lide, 1992 | LL |
13.599 | S | Kelly, 1987 | LBLHLM |
13.61 | PE | Jonathan, Morris, et al., 1970 | RDSH |
13.598 | S | Garcia and Mack, 1965 | RDSH |
De-protonation reactions
e- + =
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 1318.4 | kJ/mol | Acid | Wagman, Evans, et al., 1982 | gas phase; Using the "electron convention". Acid = H.; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 1313.8 | kJ/mol | H-TS | Wagman, Evans, et al., 1982 | gas phase; Using the "electron convention". Acid = H.; B |
Anion protonation reactions
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 1675.3 | kJ/mol | N/A | Shiell, Hu, et al., 2000 | gas phase; Given: 139714.8±1 cm-1 at 0K, or 399.465±0.003 kcal/mol; B |
ΔrH° | 1675.3 | kJ/mol | N/A | Pratt, McCormack, et al., 1992 | gas phase; 399.46±0.01 kcal/mol at 0K; 0.94 correction, Gurvich, Veyts, et al.; B |
ΔrH° | 1675.3 | kJ/mol | D-EA | Lykke, Murray, et al., 1991 | gas phase; Reported: 6082.99±0.15 cm-1, or 0.754195(18) eV; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 1649.3 ± 0.42 | kJ/mol | H-TS | Shiell, Hu, et al., 2000 | gas phase; Given: 139714.8±1 cm-1 at 0K, or 399.465±0.003 kcal/mol; B |
ΔrG° | 1649.3 | kJ/mol | H-TS | Lykke, Murray, et al., 1991 | gas phase; Reported: 6082.99±0.15 cm-1, or 0.754195(18) eV; B |
References
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.
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]
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]
Feldman, 1970
Feldman, D.,
Photoablosung von Elektronen bei einigen Stabilen Negativen Ionen,
Z. Naturfor., 1970, 25A, 621. [all data]
Lide, 1992
Lide, D.R. (Editor),
Ionization potentials of atoms and atomic ions
in Handbook of Chem. and Phys., 1992, 10-211. [all data]
Kelly, 1987
Kelly, R.L.,
Atomic and ionic spectrum lines of hydrogen through kryton,
J. Phys. Chem. Ref. Data, 1987, 16. [all data]
Jonathan, Morris, et al., 1970
Jonathan, N.; Morris, A.; Smith, D.J.; Ross, K.J.,
Photoelectron spectra of ground state atomic hydrogen, nitrogen and oxygen,
Chem. Phys. Lett., 1970, 7, 497. [all data]
Garcia and Mack, 1965
Garcia, J.D.; Mack, J.E.,
Energy level and line tables for one-electron atomic spectra,
J. Opt. Soc. Am., 1965, 55, 654. [all data]
Wagman, Evans, et al., 1982
Wagman, D.D.; Evans, W.H.; Parker, V.B.; Schumm, R.H.; Halow, I.; Bailey, S.M.; Churney, K.L.; Nuttall, R.L.,
The NBS Tables of Chemical Thermodynamic Properties (NBS Tech Note 270),
J. Phys. Chem. Ref. Data, Supl. 1, 1982, 11. [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]
Notes
Go To: Top, Gas phase ion energetics data, References
- Symbols used in this document:
EA Electron affinity IE (evaluated) Recommended ionization energy ΔfH(+) ion,0K Enthalpy of formation of positive ion at 0K ΔrG° Free energy of reaction at standard conditions ΔrH° Enthalpy of reaction at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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