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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
MM - Michael M. Meot-Ner (Mautner)
LL - Sharon G. Lias and Joel F. Liebman
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 C10H8+ (ion structure unspecified)

Quantity Value Units Method Reference Comment
IE (evaluated)7.42 ± 0.02eVN/AN/AL
Quantity Value Units Method Reference Comment
Proton affinity (review)221.1kcal/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Gas basicity214.kcal/molN/AHunter and Lias, 1998HL

Electron affinity determinations

EA (eV) Method Reference Comment
0.7900 ± 0.0080LPESSchiedt, Knott, et al., 2000B
0.69 ± 0.10TDEqChowdhury, Heinis, et al., 1986«DELTA»Gea(423 K) = -18.0 kcal/mol; «DELTA»Sea = +4.5 eu.; B
0.80 ± 0.10LPESAndo, Mitsui, et al., 2008Stated electron affinity is the Vertical Detachment Energy; B
0.690 ± 0.040ECDChen, Chen, et al., 1992B
0.681 ± 0.043KineGrimsrud, Chowdhury, et al., 1985B
0.6560 ± 0.0080ECDBecker and Chen, 1966B
<0.520 ± 0.013ECDWojnarovits and Foldiak, 1981EA is an upper limit: Chen and Wentworth, 1989. G3MP2B3 calculations indicate an EA of ca. 0.6 eV.; B
>0.460008ESChaney, Christophorou, et al., 1970Lifetime: Compton and Huebner, 1969; B

Proton affinity at 298K

Proton affinity (kcal/mol) Reference Comment
221.7Aue, Guidoni, et al., 2000Experimental literature data re-evaluated by the authors using ab initio protonation entropies; MM

Gas basicity at 298K

Gas basicity (review) (kcal/mol) Reference Comment
214.3Aue, Guidoni, et al., 2000Experimental literature data re-evaluated by the authors using ab initio protonation entropies; MM

Ionization energy determinations

IE (eV) Method Reference Comment
7.38 ± 0.03PIJochims, Rasekh, et al., 1992LL
7.32 ± 0.05EQMautner(Meot-Ner), Nelsen, et al., 1984LBLHLM
7.41 ± 0.05EQMautner(Meot-Ner), 1980LLK
7.43 ± 0.04PEBoschi, Clar, et al., 1974LLK
7.43 ± 0.01PEDewar and Worley, 1969RDSH
7.42 ± 0.05PEEland and Danby, 1968RDSH
7.41PIKitagawa, Inokuchi, et al., 1966RDSH
7.408SKitagawa, Harada, et al., 1966RDSH
7.431 ± 0.006SClark, 1965RDSH
7.4CTSFinch, 1964RDSH
7.42PEDougherty, Lewis, et al., 1980Vertical value; LLK
7.44 ± 0.03PEHeilbronner, Hoshi, et al., 1976Vertical value; LLK

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
C4H3+20.90 ± 0.102C2H2+C2HPIJochims, Rasekh, et al., 1992LL
C4H4+19.1 ± 0.1C4H2+C2H2PIJochims, Rasekh, et al., 1992LL
C4H4+17.8 ± 0.10?EIVanBrunt and Wacks, 1964RDSH
C5H3+18.5 ± 0.1C3H3+C2H2PIJochims, Rasekh, et al., 1992LL
C5H4+19.63 ± 0.15C3H3+C2HPIJochims, Rasekh, et al., 1992LL
C6H3+19.2 ± 0.15?EIVanBrunt and Wacks, 1964RDSH
C6H4+17.30 ± 0.052C2H2PIJochims, Rasekh, et al., 1992LL
C6H4+16.7 ± 0.15?EIVanBrunt and Wacks, 1964RDSH
C6H5+17.21 ± 0.05C2H2+C2HPIJochims, Rasekh, et al., 1992LL
C6H5+16.9 ± 0.10?EI2Winters and Kiser, 1964RDSH
C6H6+14.25 ± 0.05C4H2PIJochims, Rasekh, et al., 1992LL
C6H6+13.86 ± 0.05?EIVanBrunt and Wacks, 1964RDSH
C8H5+17.7 ± 0.1C2H2+HPIJochims, Rasekh, et al., 1992LL
C8H5+16.3 ± 0.15?EIVanBrunt and Wacks, 1964RDSH
C8H6+13.96 ± 0.05C2H2PIJochims, Rasekh, et al., 1992LL
C8H6+13.6 ± 0.10C2H2EIVanBrunt and Wacks, 1964RDSH
C10H6+14.2 ± 0.1H2PIJochims, Rasekh, et al., 1992LL
C10H6+14.7 ± 0.10H2EIVanBrunt and Wacks, 1964RDSH
C10H7+14.0 ± 0.1HPIJochims, Rasekh, et al., 1992LL
C10H7+14.0 ± 0.10HEIVanBrunt and Wacks, 1964RDSH

De-protonation reactions

C10H7- + Hydrogen cation = Azulene

By formula: C10H7- + H+ = C10H8

Quantity Value Units Method Reference Comment
Deltar367.7 ± 2.5kcal/molTDEqMeot-ner, Liebman, et al., 1988gas phase; Acidity seriously disagrees with high level calculations. Dissociative to acetylide? C-3is most acidic site by G3MP2B3 calns.; B
Quantity Value Units Method Reference Comment
Deltar360.2 ± 2.0kcal/molTDEqMeot-ner, Liebman, et al., 1988gas phase; Acidity seriously disagrees with high level calculations. Dissociative to acetylide? C-3is most acidic site by G3MP2B3 calns.; 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]

Schiedt, Knott, et al., 2000
Schiedt, J.; Knott, W.J.; Le Barbu, K.; Schlag, E.W.; Weinkauf, R., Microsolvation of similar-sized aromatic molecules: Photoelectron spectroscopy of bithiophene-, azulene-, and naphthalene-water anion clusters, J. Chem. Phys., 2000, 113, 21, 9470-9478, https://doi.org/10.1063/1.1319874 . [all data]

Chowdhury, Heinis, et al., 1986
Chowdhury, S.; Heinis, T.; Grimsrud, E.P.; Kebarle, P., Entropy Changes and Electron Affinities from Gas-Phase Electron Transfer Equilibria: A- + B = A + B-, J. Phys. Chem., 1986, 90, 12, 2747, https://doi.org/10.1021/j100403a037 . [all data]

Ando, Mitsui, et al., 2008
Ando, N.; Mitsui, M.; Nakajima, A., Photoelectron spectroscopy of cluster anions of naphthalene and related aromatic hydrocarbons, J. Chem. Phys., 2008, 128, 15, 154318, https://doi.org/10.1063/1.2903473 . [all data]

Chen, Chen, et al., 1992
Chen, E.C.M.; Chen, E.S.; Milligan, M.S.; Wentworth, W.E.; Wiley, J.R., Experimental Determination of the Electron Affinities of Nitrobenzene, Nitrotoluenes, Pentafluoronitrobenzene, and Isotopic Nitrobenzenes an, J. Phys. Chem., 1992, 96, 5, 2385, https://doi.org/10.1021/j100184a069 . [all data]

Grimsrud, Chowdhury, et al., 1985
Grimsrud, E.P.; Chowdhury, S.; Kebarle, P., Thermal energy electron detachment rate constants. The electron detachment from azulene- and the electron affinity of azulene, J. Chem. Phys., 1985, 83, 3983. [all data]

Becker and Chen, 1966
Becker, R.S.; Chen, E., Extension of Electron Affinities and Ionization Potentials of Aromatic Hydrocarbons, J. Chem. Phys., 1966, 45, 7, 2403, https://doi.org/10.1063/1.1727954 . [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]

Chaney, Christophorou, et al., 1970
Chaney, E.L.; Christophorou, L.G.; Collins, P.M.; Carter, J.C., Electron Attachment in the Field of the Ground and Excited States of the Azulene Molecule, J. Chem. Phys., 1970, 52, 9, 4413, https://doi.org/10.1063/1.1673666 . [all data]

Compton and Huebner, 1969
Compton, R.N.; Huebner, R.H., Temporary Attachment of Electrons to Azulene-h8 and Azulene-d8, J. Chem. Phys., 1969, 51, 7, 3132, https://doi.org/10.1063/1.1672468 . [all data]

Aue, Guidoni, et al., 2000
Aue, D.H.; Guidoni, M.; Betowski, L.D., Ab initio calculated gas-phase basicities of polynuclear aromatic hydrocarbons, Int. J. Mass Spectrom., 2000, 201, 283. [all data]

Jochims, Rasekh, et al., 1992
Jochims, H.-W.; Rasekh, H.; Ruhl, E.; Baumgartel, H.; Leach, S., The photofragmentation of naphthalene and azulene monocations in the energy range 7-22 eV, Chem. Phys., 1992, 168, 159. [all data]

Mautner(Meot-Ner), Nelsen, et al., 1984
Mautner(Meot-Ner), M.; Nelsen, S.F.; Willi, M.R.; Frigo, T.B., Special effects of an unusually large neutral to radical cation geometry change. Adiabatic ionization energies and proton affinities of alkylhydrazines, J. Am. Chem. Soc., 1984, 106, 7384. [all data]

Mautner(Meot-Ner), 1980
Mautner(Meot-Ner), M., Ion thermochemistry of low volatility compounds in the gas phase. 3. Polycyclic aromatics: Ionization energies, proton, and hydrogen affinities. Extrapolations to graphite, J. Phys. Chem., 1980, 84, 2716. [all data]

Boschi, Clar, et al., 1974
Boschi, R.; Clar, E.; Schmidt, W., Photoelectron spectra of polynuclear aromatics. III. The effect of nonplanarity in sterically overcrowded aromatic hydrocarbons, J. Chem. Phys., 1974, 60, 4406. [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]

Eland and Danby, 1968
Eland, J.H.D.; Danby, C.J., Inner ionization potentials of aromatic compounds, Z. Naturforsch., 1968, 23a, 355. [all data]

Kitagawa, Inokuchi, et al., 1966
Kitagawa, T.; Inokuchi, H.; Kodera, K., Photoionization of polycyclic aromatic compounds in vacuum ultraviolet region. Azulene, J.Mol. Spectry., 1966, 21, 267. [all data]

Kitagawa, Harada, et al., 1966
Kitagawa, T.; Harada, Y.; Inokuchi, H.; Kodera, K., Absorption spectrum of vapor phase azulene in vacuum ultraviolet region, J. Mol. Spectry., 1966, 19, 1. [all data]

Clark, 1965
Clark, L.B., Ionization potential of azulene, J. Chem. Phys., 1965, 43, 2566. [all data]

Finch, 1964
Finch, A.C.M., Charge-transfer spectra and the ionization energy of azulene, J. Chem. Soc., 1964, 2272. [all data]

Dougherty, Lewis, et al., 1980
Dougherty, D.; Lewis, J.; Nauman, R.V.; McGlynn, S.P., Photoelectron spectroscopy of azulenes, J. Electron Spectrosc. Relat. Phenom., 1980, 19, 21. [all data]

Heilbronner, Hoshi, et al., 1976
Heilbronner, E.; Hoshi, T.; von Rosenberg, J.L.; Hafner, K., Alkyl-induced, natural hypsochromic shifts of the 2A<--2X and 2B<--2X transitions of azulene and naphthalene radical cations, Nouv. J. Chim., 1976, 1, 105. [all data]

VanBrunt and Wacks, 1964
VanBrunt, R.J.; Wacks, M.E., Electron-impact studies of aromatic hydrocarbons. III. Azulene and naphthalene, J. Chem. Phys., 1964, 41, 3195. [all data]

Winters and Kiser, 1964
Winters, R.E.; Kiser, R.W., A mass spectrometric investigation of nickel tetracarbonyl and iron pentacarbonyl, Inorg. Chem., 1964, 3, 699. [all data]

Meot-ner, Liebman, et al., 1988
Meot-ner, M.; Liebman, J.F.; Kafafi, S.A., Ionic Probes of Aromaticity in Annelated Rings, J. Am. Chem. Soc., 1988, 110, 18, 5937, https://doi.org/10.1021/ja00226a001 . [all data]


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