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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:
L - Sharon G. Lias

Data compiled as indicated in comments:
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard
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)9.26eVN/AN/AL

Ionization energy determinations

IE (eV) Method Reference Comment
9.26PEGleiter, Krennrich, et al., 1986LBLHLM
9.26EILossing and Traeger, 1975LLK
9.26EIHolmes, 1974LLK
9.37 ± 0.05EIPuttemans and Delvaux, 1973LLK
9.73PEGleiter, Krennrich, et al., 1986Vertical value; LBLHLM
9.45PEDewar and Worley, 1969Vertical value; RDSH

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
C3H3+13.46 ± 0.15C2H4+HEIPuttemans and Delvaux, 1973LLK
C3H4+11.17 ± 0.08C2H4EIPuttemans and Delvaux, 1973LLK
C4H5+10.20CH3EIHolmes, 1974LLK
C4H5+10.65 ± 0.08CH3EIPuttemans and Delvaux, 1973LLK
C5H7+9.26HEILossing and Traeger, 1975, 2LLK
C5H7+9.53HEILossing and Traeger, 1975LLK
C5H7+9.53 ± 0.03HEIHolmes, 1974LLK
C5H7+9.93 ± 0.10HEIPuttemans and Delvaux, 1973LLK


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.

Gleiter, Krennrich, et al., 1986
Gleiter, R.; Krennrich, G.; Brinker, U.H., Electronic structure of spiropentane and some derivatives, J. Org. Chem., 1986, 51, 2899. [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]

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]

Puttemans and Delvaux, 1973
Puttemans, J.-P.; Delvaux, J.C., Ionisation et fragmentation d'isomeres C5H8 sous impact electronique. Spiropentane - methylenecyclobutane - isoprene, Ing. Chim. Brussell, 1973, 55(267-8), 7. [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]

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]


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