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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
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

Quantity Value Units Method Reference Comment
IE (evaluated)10.53 ± 0.02eVN/AN/AL

Ionization energy determinations

IE (eV) Method Reference Comment
10.57ESTLuo and Pacey, 1992LL
10.53 ± 0.10EVALLias, 1982LBLHLM
10.35 ± 0.15EQMautner(Meot-Ner), Sieck, et al., 1981LLK
10.6 ± 0.1PEBieri, Burger, et al., 1977LLK
10.61EQLias, Ausloos, et al., 1976LLK
10.87 ± 0.05EIFlesch and Svec, 1973LLK
10.89EIMatsumoto, Taniguchi, et al., 1970RDSH
10.67PIDewar and Worley, 1969RDSH
10.55 ± 0.05PIChupka and Berkowitz, 1967RDSH
10.50PIAl-Joboury and Turner, 1964RDSH
10.55 ± 0.05PISteiner, Giese, et al., 1961RDSH
10.63 ± 0.03PIWatanabe, 1957RDSH
11.09PEKimura, Katsumata, et al., 1981Vertical value; LLK
11.2PEBieri and Asbrink, 1980Vertical value; LLK
11.2 ± 0.1PEBieri, Burger, et al., 1977Vertical value; LLK

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
CH3+29.7 ± 0.2?EIOlmsted, Street, et al., 1964RDSH
C2H4+~11.65C2H6PIChupka and Berkowitz, 1967RDSH
C2H5+12.55C2H5EIOmura, 1961RDSH
C3H5+13.40?EIOmura, 1961RDSH
C3H6+11.15CH4EIWolkoff and Holmes, 1978LLK
C3H6+11.06CH4EIMatsumoto, Taniguchi, et al., 1970RDSH
C3H6+11.18CH4PIChupka and Berkowitz, 1967RDSH
C3H6+11.16 ± 0.03CH4PISteiner, Giese, et al., 1961RDSH
C3H7+11.2CH3EIWolkoff and Holmes, 1978LLK
C3H7+11.09CH3EIMatsumoto, Taniguchi, et al., 1970RDSH
C3H7+11.10 ± 0.05CH3EIWilliams and Hamill, 1968RDSH
C3H7+11.18CH3PIChupka and Berkowitz, 1967RDSH
C3H7+11.19 ± 0.02CH3PISteiner, Giese, et al., 1961RDSH
C4H9+10.9 ± 0.1H-PIChupka and Berkowitz, 1967RDSH
C4H9+11.7 ± 0.1HPIChupka and Berkowitz, 1967RDSH
H3+31. ± 1.?EIFuchs, 1972LLK

De-protonation reactions

C4H9- + Hydrogen cation = Butane

By formula: C4H9- + H+ = C4H10

Quantity Value Units Method Reference Comment
Δr1739. ± 8.4kJ/molBranDePuy, Gronert, et al., 1989gas phase; The HOF(Et(Me)N.) in Seetula, Russell, et al., 1990 gives BDE(N-H) = 99 kcal/mol, ca. 5 kcal/mol too strong; B
Δr1745. ± 20.kJ/molBranPeerboom, Rademaker, et al., 1992gas phase; B
Quantity Value Units Method Reference Comment
Δr1703. ± 8.8kJ/molH-TSDePuy, Gronert, et al., 1989gas phase; The HOF(Et(Me)N.) in Seetula, Russell, et al., 1990 gives BDE(N-H) = 99 kcal/mol, ca. 5 kcal/mol too strong; B
Δr1709. ± 21.kJ/molH-TSPeerboom, Rademaker, et al., 1992gas 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.

Luo and Pacey, 1992
Luo, Y.-R.; Pacey, P.D., Effects of alkyl substitution on ionization energies of alkanes and haloalkanes and on heats of formation of their molecular cations. Part 2. Alkanes and chloro-, bromo- and iodoalkanes, Int. J. Mass Spectrom. Ion Processes, 1992, 112, 63. [all data]

Lias, 1982
Lias, S.G., Thermochemical information from ion-molecule rate constants, Ion Cyclotron Reson. Spectrom. 1982, 1982, 409. [all data]

Mautner(Meot-Ner), Sieck, et al., 1981
Mautner(Meot-Ner), M.; Sieck, L.W.; Ausloos, P., Ionization of normal alkanes: Enthalpy, entropy, structural, and isotope effects, J. Am. Chem. Soc., 1981, 103, 5342. [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]

Lias, Ausloos, et al., 1976
Lias, S.G.; Ausloos, P.; Horvath, Z., Charge transfer reactions in alkane and cycloalkane systems. Estimated ionization potentials, Int. J. Chem. Kinet., 1976, 8, 725. [all data]

Flesch and Svec, 1973
Flesch, G.D.; Svec, H.J., Fragmentation reactions in the mass spectrometer for C2-C5 alkanes, J. Chem. Soc. Faraday Trans. 2, 1973, 69, 1187. [all data]

Matsumoto, Taniguchi, et al., 1970
Matsumoto, A.; Taniguchi, S.; Hayakawa, T., Studies of dissociation of hydrogen and n-butane metastable ions by a pulsed ion source in Recent Developments in Mass Spectrometry, ed. K. Ogata and T. Hayakawa, Univ. Park Press, Baltimore, MD, 1970, 820. [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]

Chupka and Berkowitz, 1967
Chupka, W.A.; Berkowitz, J., Photoionization of ethane, propane, and n-butane with mass analysis, J. Chem. Phys., 1967, 47, 2921. [all data]

Al-Joboury and Turner, 1964
Al-Joboury, M.I.; Turner, D.W., Molecular photoelectron spectroscopy. Part II. A summary of ionization potentials, J. Chem. Soc., 1964, 4434. [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]

Watanabe, 1957
Watanabe, K., Ionization potentials of some molecules, J. Chem. Phys., 1957, 26, 542. [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 and Asbrink, 1980
Bieri, G.; Asbrink, L., 30.4-nm He(II) photoelectron spectra of organic molecules, J. Electron Spectrosc. Relat. Phenom., 1980, 20, 149. [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]

Omura, 1961
Omura, I., Mass spectra at low ionizing voltage and bond dissociation energies of molecular ions from hydrocarbons, Bull. Chem. Soc. Japan, 1961, 34, 1227. [all data]

Wolkoff and Holmes, 1978
Wolkoff, P.; Holmes, J.L., Fragmentations of alkane molecular ions, J. Am. Chem. Soc., 1978, 100, 7346. [all data]

Williams and Hamill, 1968
Williams, J.M.; Hamill, W.H., Ionization potentials of molecules and free radicals and appearance potentials by electron impact in the mass spectrometer, J. Chem. Phys., 1968, 49, 4467. [all data]

Fuchs, 1972
Fuchs, R., Die kinetische energie ionisierter molekulfragmente VII. H3 ALS fragmention bei der elektronenstrossionisierung von kohlenwasserstoffen, Int. J. Mass Spectrom. Ion Processes, 1972, 8, 193. [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, https://doi.org/10.1021/ja00188a003 . [all data]

Seetula, Russell, et al., 1990
Seetula, J.A.; Russell, J.J.; Gutman, D., Kinetics and Thermochemistry of the Reactions of Alkyl Radicals with HI: A Reconciliation of the Alkyl Radical Heats of Formation, J. Am. Chem. Soc., 1990, 112, 4, 1347, https://doi.org/10.1021/ja00160a009 . [all data]

Peerboom, Rademaker, et al., 1992
Peerboom, R.A.L.; Rademaker, G.J.; Dekoning, L.J.; Nibbering, N.M.M., Stabilization of Cycloalkyl Carbanions in the Gas Phase, Rapid Commun. Mass Spectrom., 1992, 6, 6, 394, https://doi.org/10.1002/rcm.1290060608 . [all data]


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