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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:
L - Sharon G. Lias

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

Quantity Value Units Method Reference Comment
IE (evaluated)≤10.30 ± 0.08eVN/AN/AL

Ionization energy determinations

IE (eV) Method Reference Comment
10.21 ± 0.04PEJonas, Schweitzer, et al., 1973LLK
10.3 ± 0.1PEEvans, Green, et al., 1972LLK
10.40PEDewar and Worley, 1969RDSH
10.35PIWatanabe, Nakayama, et al., 1962RDSH
10.90PEKimura, Katsumata, et al., 1981Vertical value; LLK
10.9 ± 0.1PEBieri, Burger, et al., 1977Vertical value; LLK
11.3PESchmidt and Wilkins, 1972Vertical value; LLK
11.3PEMurrell and Schmidt, 1972Vertical value; LLK

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
CH3+29.5 ± 0.2?EIOlmsted, Street, et al., 1964RDSH
CH3+13.14?EILampe and Field, 1959RDSH
C2H3+17.95?EILampe and Field, 1959RDSH
C2H5+13.81?EILampe and Field, 1959RDSH
C3H3+17.08?EILampe and Field, 1959RDSH
C3H5+13.13?EILampe and Field, 1959RDSH
C4H8+10.39 ± 0.02CH4PISteiner, Giese, et al., 1961RDSH
C4H9+10.35CH3PIChesnavich, Su, et al., 1978LLK
C4H9+10.56CH3EILossing and Semeluk, 1970RDSH
C4H9+10.57 ± 0.02CH3PISteiner, Giese, et al., 1961RDSH

De-protonation reactions

C5H11- + Hydrogen cation = Neopentane

By formula: C5H11- + H+ = C5H12

Quantity Value Units Method Reference Comment
Δr1711. ± 8.4kJ/molBranDePuy, Gronert, et al., 1989gas phase; B
Δr1720. ± 42.kJ/molCIDTGraul and Squires, 1990gas phase; B
Quantity Value Units Method Reference Comment
Δr1674. ± 8.8kJ/molH-TSDePuy, Gronert, et al., 1989gas phase; 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.

Jonas, Schweitzer, et al., 1973
Jonas, A.E.; Schweitzer, G.K.; Grimm, F.A.; Carlson, T.A., The photoelectron spectra of the tetrafluoro and tetramethyl compounds of the group IV elements, J. Electron Spectrosc. Relat. Phenom., 1973, 1, 29. [all data]

Evans, Green, et al., 1972
Evans, S.; Green, J.C.; Joachim, P.J.; Orchard, A.F.; Turner, D.W.; Maier, J.P., Electronic structures of the Group IVB tetramethyls by helium-(I) photoelectron spectroscopy, J. Chem. Soc. Faraday Trans. 2, 1972, 68, 905. [all data]

Dewar and Worley, 1969
Dewar, M.J.S.; Worley, S.D., Photoelectron spectra of molecules. I. Ionization potentials of some organic molecules and their interpretation, J. Chem. Phys., 1969, 50, 654. [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]

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, Burger, et al., 1977
Bieri, G.; Burger, F.; Heilbronner, E.; Maier, J.P., Valence ionization enrgies of hydrocarbons, Helv. Chim. Acta, 1977, 60, 2213. [all data]

Schmidt and Wilkins, 1972
Schmidt, W.; Wilkins, B.T., Das "Equivalent Orbital" (EO)-verfahren zur interpretation von photoelektronen(PE)-spektren: Neopentan, Angew. Chem., 1972, 84, 168. [all data]

Murrell and Schmidt, 1972
Murrell, J.N.; Schmidt, W., Photoelectron spectroscopic correlation of the molecular orbitals of methane, ethane, propane, isobutane and neopentane, J. Chem. Soc. Faraday Trans. 2, 1972, 68, 1709. [all data]

Olmsted, Street, et al., 1964
Olmsted, J., III; Street, K., Jr.; Newton, A.S., Excess-kinetic-energy ions in organic mass spectra, J. Chem. Phys., 1964, 40, 2114. [all data]

Lampe and Field, 1959
Lampe, F.W.; Field, F.H., The decomposition of neopentane under electron impact, J. Am. Chem. Soc., 1959, 81, 3238. [all data]

Steiner, Giese, et al., 1961
Steiner, B.; Giese, C.F.; Inghram, M.G., Photoionization of alkanes. Dissociation of excited molecular ions, J. Chem. Phys., 1961, 34, 189. [all data]

Chesnavich, Su, et al., 1978
Chesnavich, W.J.; Su, T.; Bowers, M.T., Reactions of vibrationally excited ions. A theoretical and experimental analysis of the reaction (C4H9+) + NH3 Ü NH4+ + C4H8, J. Am. Chem. Soc., 1978, 100, 4362. [all data]

Lossing and Semeluk, 1970
Lossing, F.P.; Semeluk, G.P., Free radicals by mass spectrometry. XLII.Ionization potentials and ionic heats of formation for C1-C4 alkyl radicals, Can. J. Chem., 1970, 48, 955. [all data]

DePuy, Gronert, et al., 1989
DePuy, C.H.; Gronert, S.; Barlow, S.E.; Bierbaum, V.M.; Damrauer, R., The Gas Phase Acidities of the Alkanes, J. Am. Chem. Soc., 1989, 111, 6, 1968, . [all data]

Graul and Squires, 1990
Graul, S.T.; Squires, R.R., Gas-Phase Acidities Derived from Threshold Energies for Activated Reactions, J. Am. Chem. Soc., 1990, 112, 7, 2517, . [all data]


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