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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

View reactions leading to C8H8+ (ion structure unspecified)

Quantity Value Units Method Reference Comment
IE (evaluated)8.464 ± 0.001eVN/AN/AL
Quantity Value Units Method Reference Comment
Proton affinity (review)839.5kJ/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Gas basicity809.2kJ/molN/AHunter and Lias, 1998HL

Ionization energy determinations

IE (eV) Method Reference Comment
8.464 ± 0.001TEDyke, Ozeki, et al., 1992LL
8.47PEKimura, Katsumata, et al., 1981LLK
8.43PIFu and Dunbar, 1978LLK
8.2 ± 0.1EIReeher, Flesch, et al., 1976LLK
8.42PERabalais and Colton, 1973LLK
8.40 ± 0.02PEMaier and Turner, 1973LLK
8.28 ± 0.04EIBenito, Seidl, et al., 1973LLK
8.53CTSLossing and Semeluk, 1969RDSH
8.43 ± 0.01PEDewar and Worley, 1969RDSH
8.42PETurner, 1966RDSH
8.47 ± 0.02PIWatanabe, Nakayama, et al., 1962RDSH
8.48PEKobayashi, 1978Vertical value; LLK
8.58PIFu and Dunbar, 1978Vertical value; LLK
8.50PEBruckmann and Klessinger, 1974Vertical value; LLK
8.49PEKobayashi, Yokota, et al., 1973Vertical value; LLK
8.55PEBock, Wagner, et al., 1972Vertical value; LLK
8.55PEBock and Wagner, 1972Vertical value; LLK

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
C3H3+14.90 ± 0.10?EIFranklin and Carroll, 1969RDSH
C4H2+19.85 ± 0.252C2H2+H2EIFranklin and Carroll, 1969RDSH
C4H2+20.22 ± 0.102C2H2+H2EIFranklin and Carroll, 1969RDSH
C4H3+19.61 ± 0.102C2H2+HEIFranklin and Carroll, 1969RDSH
C4H4+17.25 ± 0.152C2H2EIFranklin and Carroll, 1969RDSH
C5H3+17.74 ± 0.10C2H2+CH3?EIFranklin and Carroll, 1969RDSH
C6H5+16.02 ± 0.10C2H2+HEIFranklin and Carroll, 1969RDSH
C6H6+12.38 ± 0.05C2H2EIFranklin and Carroll, 1969RDSH
C6H6+12.30 ± 0.10C2H2EIFranklin and Carroll, 1969RDSH
C8H6+12.72 ± 0.10H2EIFranklin and Carroll, 1969RDSH
C8H7+12.41 ± 0.10HEIFranklin and Carroll, 1969RDSH

De-protonation reactions

styrenide anion + Hydrogen cation = Styrene

By formula: C8H7- + H+ = C8H8

Quantity Value Units Method Reference Comment
Δr1636. ± 10.kJ/molTDEqMeot-ner and Kafafi, 1988gas phase; Acid: styrene. AM1 says ortho deprotonation prefered to alpha. Anchored to 88MEO scale.; B
Quantity Value Units Method Reference Comment
Δr1604. ± 8.4kJ/molTDEqMeot-ner and Kafafi, 1988gas phase; Acid: styrene. AM1 says ortho deprotonation prefered to alpha. Anchored to 88MEO scale.; 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]

Dyke, Ozeki, et al., 1992
Dyke, J.M.; Ozeki, H.; Takahashi, M.; Cockett, M.C.R.; Kimura, K., A study of phenylacetylene and styrene, and their argon complexes PA-Ar and ST-Ar with laser threshold photoelectron spectroscopy, J. Chem. Phys., 1992, 97, 8926. [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]

Fu and Dunbar, 1978
Fu, E.W.; Dunbar, R.C., Photodissociation spectroscopy and structural rearrangements in ions of cyclooctatetraene, styrene and related molecules, J. Am. Chem. Soc., 1978, 100, 2283. [all data]

Reeher, Flesch, et al., 1976
Reeher, J.R.; Flesch, G.D.; Svec, H.J., The mass spectra and ionization potentials of the neutral fragments produced during the electron bombardment of aromatic compounds, Org. Mass Spectrom., 1976, 11, 154. [all data]

Rabalais and Colton, 1973
Rabalais, J.W.; Colton, R.J., Electronic interaction between the phenyl group and its unsaturated substituents, J. Electron Spectrosc. Relat. Phenom., 1973, 1, 83. [all data]

Maier and Turner, 1973
Maier, J.P.; Turner, D.W., Steric inhibition of resonance studied by molecular photoelectron spectroscopy. Part 2. Phenylethylenes, J. Chem. Soc. Faraday Trans. 2, 1973, 69, 196. [all data]

Benito, Seidl, et al., 1973
Benito, I.; Seidl, H.; Bock, H., Efectos electronicos y estericos de sustituyentes alquilicos y silicicos sobre el sistema electronico π del estireno, Rev. Fac. Cienc. Univ. Oviedo, 1973, 14, 95. [all data]

Lossing and Semeluk, 1969
Lossing, F.P.; Semeluk, G.P., Threshold ionization efficiency curves for monoenergetic electron impact on H2, D2, CH4 and CD4, Intern. J. Mass Spectrom. Ion Phys., 1969, 2, 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]

Turner, 1966
Turner, D.W., Ionization potentials, Advan. Phys. Org. Chem., 1966, 4, 31. [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]

Kobayashi, 1978
Kobayashi, T., A simple general tendency in photoelectron angular distributions of some monosubstituted benzenes, Phys. Lett., 1978, 69, 105. [all data]

Bruckmann and Klessinger, 1974
Bruckmann, P.; Klessinger, M., Photoelektronenspektren organischer verbindungen. V. Wechselwirkung kleiner ringe mit π-systemen, Chem. Ber., 1974, 107, 1108. [all data]

Kobayashi, Yokota, et al., 1973
Kobayashi, T.; Yokota, K.; Nagakura, S., Photoelectron spectra of styrenes, J. Electron Spectrosc. Relat. Phenom., 1973, 3, 449. [all data]

Bock, Wagner, et al., 1972
Bock, H.; Wagner, G.; Kroner, J., Photoelektronenspektren und molekuleigenschaften, XIV. Die delokalisation des schwefel-elektronenpaar in CH3S-substituierten aromaten, Chem. Ber., 1972, 105, 3850. [all data]

Bock and Wagner, 1972
Bock, H.; Wagner, G., Electron lone pairs in organic sulfides and disulfides, Angew. Chem. Int. Ed. Engl., 1972, 11, 119. [all data]

Franklin and Carroll, 1969
Franklin, J.L.; Carroll, S.R., The effect of molecular structure on ionic decomposition. I. An electron impact study of seven C8H8 isomers, J. Am. Chem. Soc., 1969, 91, 5940. [all data]

Meot-ner and Kafafi, 1988
Meot-ner, M.; Kafafi, S.A., Carbon Acidities of Aromatic Compounds, J. Am. Chem. Soc., 1988, 110, 19, 6297, . [all data]


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