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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:
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

Quantity Value Units Method Reference Comment
Proton affinity (review)802.0kJ/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Gas basicity769.5kJ/molN/AHunter and Lias, 1998HL

Electron affinity determinations

EA (eV) Method Reference Comment
<0.156 ± 0.043ECDWojnarovits and Foldiak, 1981EA is an upper limit: Chen and Wentworth, 1989. G3MP2B3 calculations indicate an EA of ca. -0.3 eV, anion unbound.; B

Ionization energy determinations

IE (eV) Method Reference Comment
9.4EITerlouw, Heerma, et al., 1974LLK
8.7 ± 0.1EIBohlmann, Koppel, et al., 1974LLK
8.55 ± 0.03PIPotapov, Kardash, et al., 1972LLK
9.00 ± 0.05EIPignataro, Mancini, et al., 1972LLK
8.67 ± 0.05PEDistefano, Pignataro, et al., 1976Vertical value; LLK
8.8PEEaton and Traylor, 1974Vertical value; LLK
8.80 ± 0.02PEMaier and Turner, 1973Vertical value; LLK
9.1PEPignataro, Mancini, et al., 1971Vertical value; LLK

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
C7H7+11.5 ± 0.1C6H5EIInnorta, Torroni, et al., 1973LLK
C13H9+14.9 ± 0.1H2+HEIRapp, Staab, et al., 1970RDSH
C13H11+11.2 ± 0.1HEIBohlmann, Koppel, et al., 1974LLK

De-protonation reactions

C13H11- + Hydrogen cation = Diphenylmethane

By formula: C13H11- + H+ = C13H12

Quantity Value Units Method Reference Comment
Δr1521. ± 8.8kJ/molG+TSBartmess, Scott, et al., 1979gas phase; value altered from reference due to change in acidity scale; B
Δr1512. ± 9.6kJ/molG+TSCumming and Kebarle, 1978gas phase; B
Quantity Value Units Method Reference Comment
Δr1499. ± 8.4kJ/molIMREBartmess, Scott, et al., 1979gas phase; value altered from reference due to change in acidity scale; B
Δr1489. ± 8.4kJ/molIMRECumming and Kebarle, 1978gas phase; 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, https://doi.org/10.1063/1.556018 . [all data]

Wojnarovits and Foldiak, 1981
Wojnarovits, L.; Foldiak, G., Electron capture detection of aromatic hydrocarbons, J. Chromatogr. Sci., 1981, 206, 511. [all data]

Chen and Wentworth, 1989
Chen, E.C.M.; Wentworth, W.E., Experimental Determination of Electron Affinities of Organic Molecules, Mol. Cryst. Liq. Cryst., 1989, 171, 271. [all data]

Terlouw, Heerma, et al., 1974
Terlouw, J.K.; Heerma, W.; Frintrop, P.C.M.; Dijkstra, G.; Meinema, H.A., Electron-impact induced fragmentation of some heterocyclic-tin compounds, J. Organomet. Chem., 1974, 64, 205. [all data]

Bohlmann, Koppel, et al., 1974
Bohlmann, F.; Koppel, C.; Muller, B.; Schwarz, H.; Weyerstahl, P., Massenspektrometrische Untersuchung isomerer Kohlenwasserstoffe: Struktur und Bildungsenthalpie stabiler (C13H11+) Ionen, Tetrahedron, 1974, 30, 1011. [all data]

Potapov, Kardash, et al., 1972
Potapov, V.K.; Kardash, I.E.; Sorokin, V.V.; Sokolov, S.A.; Evlasheva, T.I., Photoionization of heteroaromatic compounds, Khim. Vys. Energ., 1972, 6, 392. [all data]

Pignataro, Mancini, et al., 1972
Pignataro, S.; Mancini, V.; Innorta, G.; Distefano, G., Ionization energies and ring orbital interaction in diarylmethanes and diaryleth, Z. Naturforsch., 1972, 27, 534. [all data]

Distefano, Pignataro, et al., 1976
Distefano, G.; Pignataro, S.; Szepes, L.; Borossay, J., Photoelectron spectroscopy study of the triphenyl derivatives of the group IV elements, J. Organomet. Chem., 1976, 104, 173. [all data]

Eaton and Traylor, 1974
Eaton, D.F.; Traylor, T.G., Distortional stabilization in phenyl participations, J. Am. Chem. Soc., 1974, 96, 7109. [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]

Pignataro, Mancini, et al., 1971
Pignataro, S.; Mancini, V.; Ridyard, J.N.A.; Lempka, H.J., Photoelectron energy spectra of molecules having classically non-conjugated π-systems, Chem. Commun., 1971, 142. [all data]

Innorta, Torroni, et al., 1973
Innorta, G.; Torroni, S.; Pignataro, S.; Mancini, V., The activation energy as guiding factor in the fragmentation of substituted diphenylmethanes, Org. Mass Spectrom., 1973, 7, 1399. [all data]

Rapp, Staab, et al., 1970
Rapp, U.; Staab, H.A.; Wunsche, C., Skelettumlagerungen unter Elektronenbeschuss-IV: zur Struktur der C13H9- und C12H9N-Ionen bei Benzylidenaminobenztriazolen, Org. Mass Spectrom., 1970, 3, 45. [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]

Cumming and Kebarle, 1978
Cumming, J.B.; Kebarle, P., Summary of gas phase measurements involving acids AH. Entropy changes in proton transfer reactions involving negative ions. Bond dissociation energies D(A-H) and electron affinities EA(A), Can. J. Chem., 1978, 56, 1. [all data]


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