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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
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard

Quantity Value Units Method Reference Comment
IE (evaluated)10.94 ± 0.05eVN/AN/AL
Quantity Value Units Method Reference Comment
Proton affinity (review)625.7kJ/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Gas basicity607.8kJ/molN/AHunter and Lias, 1998HL

Ionization energy determinations

IE (eV) Method Reference Comment
11. ± 1.PIAu, Cooper, et al., 1993LL
10.96ESTLuo and Pacey, 1992LL
10.9 ± 0.1PEBieri, Burger, et al., 1977LLK
11.27 ± 0.05EIFlesch and Svec, 1973LLK
11.01 ± 0.07EIFinney and Harrison, 1972LLK
10.94 ± 0.05TEStockbauer and Inghram, 1971LLK
10.97PIVlaskov and Ovchinnikov, 1969RDSH
11.06PEDewar and Worley, 1969RDSH
11.09 ± 0.05EIWilliams and Hamill, 1968RDSH
11.12CICermak, 1968RDSH
10.95 ± 0.05PIChupka and Berkowitz, 1967RDSH
11.22EILifshitz and Shapiro, 1966RDSH
11.07PETurner and Al-Joboury, 1964RDSH
11.07PEAl-Joboury and Turner, 1964RDSH
11.51PEKimura, Katsumata, et al., 1981Vertical value; LLK
11.5PEBieri and Asbrink, 1980Vertical value; LLK
11.5 ± 0.1PEBieri, Burger, et al., 1977Vertical value; LLK
11.5PEMurrell and Schmidt, 1972Vertical value; LLK

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
CH+40. ± 1.?PIAu, Cooper, et al., 1993LL
CH+26. ± 1.C2H5++H2EIEhrhardt and Tekaat, 1964RDSH
CH2+25. ± 1.?PIAu, Cooper, et al., 1993LL
CH3+21. ± 1.C2H5PIAu, Cooper, et al., 1993LL
CH3+30. ± 1.C2H5EIFuchs, 1972LLK
CH3+14.0 ± 0.5C2H5EIAppell, Durup, et al., 1966RDSH
CH3+22.0 ± 0.5C2H5+EIEhrhardt and Tekaat, 1964RDSH
CH3+25.0 ± 0.5C2H+3+H2EIEhrhardt and Tekaat, 1964RDSH
C2H+32. ± 1.?PIAu, Cooper, et al., 1993LL
C2H+30.4 ± 0.5C+3+2H2EIEhrhardt and Tekaat, 1964RDSH
C2H2+15. ± 1.?PIAu, Cooper, et al., 1993LL
C2H2+14.1 ± 0.15CH4+H2EIEhrhardt and Tekaat, 1964RDSH
C2H2+29. ± 1.CH+3+H2+HEIEhrhardt and Tekaat, 1964RDSH
C2H3+14. ± 1.?PIAu, Cooper, et al., 1993LL
C2H3+14.5 ± 0.15?EIEhrhardt and Tekaat, 1964RDSH
C2H3+25.0 ± 0.5CH+3+H2EIEhrhardt and Tekaat, 1964RDSH
C2H4+11. ± 1.CH4PIAu, Cooper, et al., 1993LL
C2H4+11.69 ± 0.03CH4PIPECOGilman, Hsieh, et al., 1982LBLHLM
C2H4+11.52CH4EIWolkoff and Holmes, 1978LLK
C2H4+11.55CH4EIHickling and Jennings, 1970RDSH
C2H4+11.9CH4EIHickling and Jennings, 1970RDSH
C2H4+11.72 ± 0.02CH4PIChupka and Berkowitz, 1967RDSH
C2H4+11.5 ± 0.1CH4EILifshitz and Shapiro, 1966RDSH
C2H4+11.70CH4EILifshitz and Shapiro, 1966RDSH
C2H4+27.2 ± 0.5CH2++H2?EIEhrhardt and Tekaat, 1964RDSH
C2H5+11. ± 1.CH3PIAu, Cooper, et al., 1993LL
C2H5+12.02 ± 0.05CH3EIWilliams and Hamill, 1968RDSH
C2H5+11.90 ± 0.08CH3PIChupka and Berkowitz, 1967RDSH
C2H5+21. ± 2.CH3+EIEhrhardt and Tekaat, 1964RDSH
C2H5+26.9 ± 0.5CH++H2EIEhrhardt and Tekaat, 1964RDSH
C3H+29. ± 1.?PIAu, Cooper, et al., 1993LL
C3H2+26. ± 1.?PIAu, Cooper, et al., 1993LL
C3H3+17. ± 1.?PIAu, Cooper, et al., 1993LL
C3H4+15. ± 1.?PIAu, Cooper, et al., 1993LL
C3H5+14. ± 1.H2+HPIAu, Cooper, et al., 1993LL
C3H5+14.76H2+HEIOmura, 1961RDSH
C3H6+12. ± 1.H2PIAu, Cooper, et al., 1993LL
C3H6+11.75 ± 0.05H2PIChupka and Berkowitz, 1967RDSH
C3H7+11. ± 1.HPIAu, Cooper, et al., 1993LL
C3H7+11.57 ± 0.05HEIWilliams and Hamill, 1968RDSH
C3H7+11.59 ± 0.01HPIChupka and Berkowitz, 1967RDSH
C3H7+~11.0H-PIChupka and Berkowitz, 1967RDSH
C3H7+11.52HEILifshitz and Shapiro, 1966RDSH
C3H7+11.59 ± 0.03HPISteiner, Giese, et al., 1961RDSH
H+22. ± 1.?PIAu, Cooper, et al., 1993LL
H+20.0 ± 0.3?EIEhrhardt and Tekaat, 1964RDSH
H2+43. ± 1.?PIAu, Cooper, et al., 1993LL
H2+16.4 ± 0.5?EIEhrhardt and Tekaat, 1964RDSH
H3+32. ± 1.?EIFuchs, 1972LLK

De-protonation reactions

C3H7- + Hydrogen cation = Propane

By formula: C3H7- + H+ = C3H8

Quantity Value Units Method Reference Comment
Δr1755. ± 8.4kJ/molBranDePuy, Gronert, et al., 1989gas phase; B
Δr1755. ± 20.kJ/molBranPeerboom, Rademaker, et al., 1992gas phase; B
Δr1753. ± 8.4kJ/molBranDePuy, Bierbaum, et al., 1984gas phase; B
Quantity Value Units Method Reference Comment
Δr1721. ± 8.8kJ/molH-TSDePuy, Gronert, et al., 1989gas phase; B
Δr1722. ± 21.kJ/molH-TSPeerboom, Rademaker, et al., 1992gas phase; B

EtCH2 anion + Hydrogen cation = Propane

By formula: C3H7- + H+ = C3H8

Quantity Value Units Method Reference Comment
Δr1739. ± 8.4kJ/molBranDePuy, Gronert, et al., 1989gas phase; B
Quantity Value Units Method Reference Comment
Δr1704. ± 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.

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, . [all data]

Au, Cooper, et al., 1993
Au, J.W.; Cooper, G.; Brion, C.E., The molecular and dissociative photoionization of ethane, propane, and n-butane: Absolute oscillator strengths (10-80 eV) and breakdown pathways, Chem. Phys., 1993, 173, 241. [all data]

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]

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]

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]

Finney and Harrison, 1972
Finney, C.D.; Harrison, A.G., A third-derivative method for determining electron-impact onset potentials, Int. J. Mass Spectrom. Ion Phys., 1972, 9, 221. [all data]

Stockbauer and Inghram, 1971
Stockbauer, R.; Inghram, M.G., Experimental relative Franck-Condon factors for the ionization of methane, ethane, and propane, J. Chem. Phys., 1971, 54, 2242. [all data]

Vlaskov and Ovchinnikov, 1969
Vlaskov, V.A.; Ovchinnikov, A.A., The temperature dependence of the photoionization cross-section of polyatomic molecules, Opt. i Spektroskopiya, 1969, 27, 748, In original 408. [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]

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]

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]

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]

Lifshitz and Shapiro, 1966
Lifshitz, C.; Shapiro, M., Isotope effects on metastable transitions: C3H8 and C3D8, J. Chem. Phys., 1966, 45, 4242. [all data]

Turner and Al-Joboury, 1964
Turner, D.W.; Al-Joboury, M.I., Molecular photoelectron spectroscopy, Bull. Soc. Chim. Belges, 1964, 73, 428. [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]

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]

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]

Ehrhardt and Tekaat, 1964
Ehrhardt, H.; Tekaat, T., Auftrittspotentialmessungen an ionisierten Molekulbruchstucken mit kinetischer Anfangsenergie, Z. Naturforsch., 1964, 19a, 1382. [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]

Appell, Durup, et al., 1966
Appell, J.; Durup, J.; Heitz, F., Sur le seuil d'apparition des ions fragments produits avec exces d'energie cinetique, Advan. Mass Spectrom., 1966, 3, 457. [all data]

Gilman, Hsieh, et al., 1982
Gilman, J.P.; Hsieh, T.; Meisels, G.G., Carbon skeletal rearrangement of the propane ion, J. Chem. Phys., 1982, 76, 3497. [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]

Hickling and Jennings, 1970
Hickling, R.D.; Jennings, K.R., Kinetic shifts and metastable transitions, Org. Mass Spectrom., 1970, 3, 1499. [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]

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]

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]

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, . [all data]

DePuy, Bierbaum, et al., 1984
DePuy, C.H.; Bierbaum, V.M.; Damrauer, R., Relative Gas-Phase Acidities of the Alkanes, J. Am. Chem. Soc., 1984, 106, 4051. [all data]


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