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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

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
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard

View reactions leading to C6H8+ (ion structure unspecified)

Quantity Value Units Method Reference Comment
Proton affinity (review)200.kcal/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Gas basicity193.1kcal/molN/AHunter and Lias, 1998HL

Ionization energy determinations

IE (eV) Method Reference Comment
8.82PEKimura, Katsumata, et al., 1981LLK
8.82 ± 0.02PEBieri, Burger, et al., 1977LLK
8.82 ± 0.02PIDemeo and El-Sayed, 1970RDSH
8.65 ± 0.05EIFranklin and Carroll, 1969RDSH
8.80PEBischof, Hashmall, et al., 1969RDSH
8.82PEKimura, Katsumata, et al., 1981Vertical value; LLK
8.82PEBock and Kaim, 1980Vertical value; LLK
8.80PEKobayashi, 1978Vertical value; LLK
8.82PEHeilbronner, Brogli, et al., 1976Vertical value; LLK

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
C3H2+19.21 ± 0.15?EIFranklin and Carroll, 1969RDSH
C3H3+15.20 ± 0.10?EIFranklin and Carroll, 1969RDSH
C3H4+13.95 ± 0.10?EIFranklin and Carroll, 1969RDSH
C4H2+17.82 ± 0.25C2H2+2H2EIFranklin and Carroll, 1969RDSH
C4H3+17.08 ± 0.10C2H2+H2+H?EIFranklin and Carroll, 1969RDSH
C4H4+13.55 ± 0.10C2H2+H2EIFranklin and Carroll, 1969RDSH
C4H5+14.48 ± 0.10C2H2+HEIFranklin and Carroll, 1969RDSH
C4H6+12.17 ± 0.10C2H2EIFranklin and Carroll, 1969RDSH
C5H3+16.12 ± 0.10CH3+H2?EIFranklin and Carroll, 1969RDSH
C5H5+13.41 ± 0.10CH3EIFranklin and Carroll, 1969RDSH
C5H5+13.6CH3EIHarrison, Haynes, et al., 1965RDSH
C6H5+13.92 ± 0.10H2+HEIFranklin and Carroll, 1969RDSH
C6H6+9.61 ± 0.10H2EIFranklin and Carroll, 1969RDSH
C6H6+9.86 ± 0.05H2EIFranklin and Carroll, 1969RDSH
C6H7+10.55HPIPECOLias and Ausloos, 1985LBLHLM
C6H7+10.94 ± 0.10HEIFranklin and Carroll, 1969RDSH


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]

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]

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]

Franklin and Carroll, 1969
Franklin, J.L.; Carroll, S.R., Effect of molecular structure on ionic decomposition. II. An electron-impact study of 1,3-and 1,4-cyclohexadiene and 1,3,5-hexatriene, J. Am. Chem. Soc., 1969, 91, 6564. [all data]

Bischof, Hashmall, et al., 1969
Bischof, P.; Hashmall, J.A.; Heilbronner, E.; Hornung, V., Photoelektronspektroskopische Bestimmung der Wechselwirkung zwischen nichtkonjugierten Doppelbindungen, Helv. Chim. Acta, 1969, 52, 1745. [all data]

Bock and Kaim, 1980
Bock, H.; Kaim, W., Radical ions. 37. Ionization and one-electron oxidation of electron-rich silylalkyl olefins, J. Am. Chem. Soc., 1980, 102, 4429. [all data]

Kobayashi, 1978
Kobayashi, T., A new rule for photoelectron angular distributions of molecules, Phys. Lett. A, 1978, 69, 31. [all data]

Heilbronner, Brogli, et al., 1976
Heilbronner, E.; Brogli, F.; Vogel, E., Photoelectron spectroscopic assignment of symmetry to the ground state and first excited state of the 1,4-cyclohexadiene radical cation, J. Electron Spectrosc. Relat. Phenom., 1976, 9, 227. [all data]

Harrison, Haynes, et al., 1965
Harrison, A.G.; Haynes, P.; McLean, S.; Meyer, F., The mass spectra of methyl-substituted cyclopentadienes, J. Am. Chem. Soc., 1965, 87, 5099. [all data]

Lias and Ausloos, 1985
Lias, S.G.; Ausloos, P., Structures of C6H7+ ions formed in unimolecular and bimolecular reactions, J. Chem. Phys., 1985, 82, 3613. [all data]


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