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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 compiled as indicated in comments:
B - John E. Bartmess
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 C7H8+ (ion structure unspecified)

Ionization energy determinations

IE (eV) Method Reference Comment
8.29PITraeger and McLoughlin, 1978LLK
8.03PETraeger and McLoughlin, 1978LLK
8.52EIHoffman, 1974LLK
8.40PEBodor, Dewar, et al., 1970RDSH
8.20 ± 0.05PIAkopyan and Vilesov, 1966RDSH
8.28SPrice, Passmore, et al., 1963RDSH
8.50PEMuller, Schweig, et al., 1974Vertical value; LLK

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
C5H5+16.66?EIHarrison, Haynes, et al., 1965RDSH
C5H5+16.0?EILifshitz and Bauer, 1963RDSH
C6H5+14.17CH3EIHoffman, 1974LLK
C7H7+9.36HPITraeger and McLoughlin, 1978LLK
C7H7+9.36 ± 0.02HTETraeger and McLoughlin, 1977LLK
C7H7+10.73HEIHoffman, 1974LLK
C7H7+≤10.0HPIAkopyan and Vilesov, 1966RDSH
C7H7+10.1 ± 0.2HEIHarrison, Honnen, et al., 1960RDSH

De-protonation reactions

C7H7- + Hydrogen cation = 1,3,5-Cycloheptatriene

By formula: C7H7- + H+ = C7H8

Quantity Value Units Method Reference Comment
Δr1570. ± 9.2kJ/molG+TSBartmess, Scott, et al., 1979gas phase; value altered from reference due to change in acidity scale; B
Quantity Value Units Method Reference Comment
Δr1545. ± 8.4kJ/molIMREBartmess, Scott, et al., 1979gas phase; value altered from reference due to change in acidity 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.

Traeger and McLoughlin, 1978
Traeger, J.C.; McLoughlin, R.G., A photoionization study of the energetics of C7H7+ ion formed from C7H8 precursors, Int. J. Mass Spectrom. Ion Phys., 1978, 27, 319. [all data]

Hoffman, 1974
Hoffman, M.K., Hidden rearrangements in the mass spectral decomposition of cycloheptatriene, Z. Naturforsch. A:, 1974, 29, 1077. [all data]

Bodor, Dewar, et al., 1970
Bodor, N.; Dewar, M.J.S.; Worley, S.D., Photoelectron spectra of molecules. III. Ionization potentials of some cyclic hydrocarbons and their derivatives, and heats of formation and ionization potentials calculated by the MINDO SCF MO method, J. Am. Chem. Soc., 1970, 92, 19. [all data]

Akopyan and Vilesov, 1966
Akopyan, M.E.; Vilesov, F.I., A mass-spectrometric study of the photo-ionisation of benzene derivatives at wavelengths up to 885 A, Zh. Fiz. Khim., 1966, 40, 125, In original 63. [all data]

Price, Passmore, et al., 1963
Price, W.C.; Passmore, T.R.; Roessler, D.M., [Title unavailable], Faraday Discuss. Chem. Soc., 1963, 35, 238. [all data]

Muller, Schweig, et al., 1974
Muller, C.; Schweig, A.; Vermeer, H., Methode zur Berechnung induktiver und konjugativer Effekte - Andwendung auf Tropon, Angew. Chem., 1974, 86, 275. [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]

Lifshitz and Bauer, 1963
Lifshitz, C.; Bauer, S.H., Mass spectra of valence tautomers, J. Phys. Chem., 1963, 67, 1629. [all data]

Traeger and McLoughlin, 1977
Traeger, J.C.; McLoughlin, R.G., Threshold photoionization and dissociation of toluene and cycloheptatriene, J. Am. Chem. Soc., 1977, 99, 7351. [all data]

Harrison, Honnen, et al., 1960
Harrison, A.G.; Honnen, L.R.; Dauben, H.J., Jr.; Lossing, F.P., Free radicals by mass spectrometry. XX. Ionization potentials of cyclopentadienyl and cycloheptatrienyl radicals, J. Am. Chem. Soc., 1960, 82, 5593. [all data]

Bartmess, Scott, et al., 1979
Bartmess, J.E.; Scott, J.A.; McIver, R.T., Jr., The gas phase acidity scale from methanol to phenol, J. Am. Chem. Soc., 1979, 101, 6047. [all data]


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