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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:
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 C5H8+ (ion structure unspecified)

Quantity Value Units Method Reference Comment
IE (evaluated)9.01 ± 0.01eVN/AN/AL
Quantity Value Units Method Reference Comment
Proton affinity (review)766.3kJ/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Gas basicity733.8kJ/molN/AHunter and Lias, 1998HL

Ionization energy determinations

IE (eV) Method Reference Comment
9.18PEKimura, Katsumata, et al., 1981LLK
9.1EIHarris, McKinnon, et al., 1979LLK
9.01 ± 0.02PEBieri, Burger, et al., 1977LLK
9.00EILossing and Traeger, 1975LLK
9.02 ± 0.01PERang, Paldoia, et al., 1974LLK
9.00EIHolmes, 1974LLK
9.01 ± 0.01PEPraet and Delwiche, 1970RDSH
9.02 ± 0.01PIDemeo and El-Sayed, 1970RDSH
9.01PEBischof and Heilbronner, 1970RDSH
9.00PEDewar and Worley, 1969RDSH
9.01 ± 0.01PIWatanabe, Nakayama, et al., 1962RDSH
9.20PEWiberg, Ellison, et al., 1976Vertical value; LLK
9.01 ± 0.03PEHeilbronner, Hoshi, et al., 1976Vertical value; LLK
9.17PEBertoti, Cradock, et al., 1976Vertical value; LLK
9.12PEHentrich, Gunkel, et al., 1974Vertical value; LLK
9.18PEClary, Lewis, et al., 1974Vertical value; LLK
9.20PEBatich, Heilbronner, et al., 1974Vertical value; LLK

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
C4H5+11.83CH3EIHolmes, 1974LLK
C5H7+9.00HEILossing and Traeger, 1975, 2LLK
C5H7+10.98HEILossing and Traeger, 1975LLK
C5H7+10.98HEIHolmes, 1974LLK
C5H7+11.19HEIPignataro, Cassuto, et al., 1967RDSH


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, https://doi.org/10.1063/1.556018 . [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]

Harris, McKinnon, et al., 1979
Harris, D.; McKinnon, S.; Boyd, R.K., The origins of the base peak in the electron impact spectrum of limonene, Org. Mass Spectrom., 1979, 14, 265. [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]

Lossing and Traeger, 1975
Lossing, F.P.; Traeger, J.C., Stabilization in cyclopentadienyl, cyclopentenyl, and cyclopentyl cations, J. Am. Chem. Soc., 1975, 97, 1579. [all data]

Rang, Paldoia, et al., 1974
Rang, S.; Paldoia, P.; Talvari, A., Ionization potentials of unsaturated hydrocarbons. 2. Mono-substituted cyclopentenes and cyclohexenes, Eesti. NSV Tead. Akad. Toim., 1974, 354. [all data]

Holmes, 1974
Holmes, J.L., The mass spectra of isomeric hydrocarbons - II: The C5H8 isomers, spiropentane, cyclopentene, 1,3-pentadiene and isoprene; the mechanisms and energetics of their fragmentations, Org. Mass Spectrom., 1974, 8, 247. [all data]

Praet and Delwiche, 1970
Praet, M.-T.; Delwiche, J., Ionization energies of some cyclic molecules, Chem. Phys. Lett., 1970, 5, 546. [all data]

Demeo and El-Sayed, 1970
Demeo, D.A.; El-Sayed, M.A., Ionization potential and structure of olefins, J. Chem. Phys., 1970, 52, 2622. [all data]

Bischof and Heilbronner, 1970
Bischof, P.; Heilbronner, E., Photoelektron-Spektren von Cycloalkenen und Cycloalkadienen, Helv. Chim. Acta, 1970, 53, 1677. [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]

Wiberg, Ellison, et al., 1976
Wiberg, K.B.; Ellison, G.B.; Wendoloski, J.J.; Brundle, C.R.; Kuebler, N.A., Electronic states of organic molecules. 3. Photoelectron spectra of cycloalkenes and methylenecycloalkanes, J. Am. Chem. Soc., 1976, 98, 7179. [all data]

Heilbronner, Hoshi, et al., 1976
Heilbronner, E.; Hoshi, T.; von Rosenberg, J.L.; Hafner, K., Alkyl-induced, natural hypsochromic shifts of the 2A<--2X and 2B<--2X transitions of azulene and naphthalene radical cations, Nouv. J. Chim., 1976, 1, 105. [all data]

Bertoti, Cradock, et al., 1976
Bertoti, I.; Cradock, S.; Ebsworth, E.A.V.; Whiteford, R.A., Photoelectron spectra and transannular interactions in 1-silacyclopent-3-enes, J. Chem. Soc. Dalton Trans., 1976, 937. [all data]

Hentrich, Gunkel, et al., 1974
Hentrich, G.; Gunkel, E.; Klessinger, M., Photoelektronenspektren organischer verbindungen. 4. Photoelektronenspektren ungesattigter carbonylverbindungen, J. Mol. Struct., 1974, 21, 231. [all data]

Clary, Lewis, et al., 1974
Clary, D.C.; Lewis, A.A.; Morland, D.; Murrell, J.N.; Heilbronner, E., Ionization potentials of cycloalkenes, J. Chem. Soc. Faraday Trans. 2, 1974, 70, 1889. [all data]

Batich, Heilbronner, et al., 1974
Batich, C.; Heilbronner, E.; Rommel, E.; Semmelhack, M.F.; Foos, J.S., Equivalence of the energy gaps {DELTA}I(1,2) and {DELTA}E(1,2) between corresponding bands in the photoelectron (I) and electronic absorption (E) spectra of spiro[4.4]nonatetraene. An amusing consequence of spiroconjugation, J. Am. Chem. Soc., 1974, 96, 7662. [all data]

Lossing and Traeger, 1975, 2
Lossing, F.P.; Traeger, J.C., Free radicals by mass spectrometry XLVI. Heats of formation of C5H7 and C5H9 radicals and cations., J. Am. Chem. Soc., 1975, 19, 9. [all data]

Pignataro, Cassuto, et al., 1967
Pignataro, S.; Cassuto, A.; Lossing, F.P., Free radicals by mass spectrometry. XXXVI. Ionization potentials of conjugated and nonconjugated radicals, J. Am. Chem. Soc., 1967, 89, 3693. [all data]


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