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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

View reactions leading to C4H2+ (ion structure unspecified)

Quantity Value Units Method Reference Comment
Proton affinity (review)737.2kJ/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Gas basicity712.8kJ/molN/AHunter and Lias, 1998HL

Ionization energy determinations

IE (eV) Method Reference Comment
10.17PEBieri, Schmelzer, et al., 1980LLK
10.17 ± 0.02PEBieri, Burger, et al., 1977LLK
10.1 ± 0.1EIReeher, Flesch, et al., 1976LLK
10.17PEBrogli, Heilbronner, et al., 1973LLK
10.180 ± 0.003SSmith, 1967RDSH
10.17 ± 0.01PEBaker and Turner, Commun. 1967RDSH
10.30PEBieri and Asbrink, 1980Vertical value; LLK

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
C2H+20.1 ± 0.5C2HEICoats and Anderson, 1957RDSH
C4H+12.1 ± 0.3HEICoats and Anderson, 1957RDSH

De-protonation reactions

C4H- + Hydrogen cation = 1,3-Butadiyne

By formula: C4H- + H+ = C4H2

Quantity Value Units Method Reference Comment
Deltar1507. ± 13.kJ/molD-EAPino, Tulej, et al., 2002gas phase; B
Deltar1508. ± 12.kJ/molEndoShi and Ervin, 2000gas phase; B
Quantity Value Units Method Reference Comment
Deltar1473. ± 14.kJ/molH-TSPino, Tulej, et al., 2002gas phase; B
Deltar1474. ± 13.kJ/molH-TSShi and Ervin, 2000gas 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]

Bieri, Schmelzer, et al., 1980
Bieri, G.; Schmelzer, A.; Asbrink, L.; Jonsson, M., Fluorine and the fluoroderivatives of acetylene and diacetylene studied by 30.4 nm He(II) photoelectron spectroscopy, Chem. Phys., 1980, 49, 213. [all data]

Bieri, Burger, et al., 1977
Bieri, G.; Burger, F.; Heilbronner, E.; Maier, J.P., Valence ionization enrgies of hydrocarbons, Helv. Chim. Acta, 1977, 60, 2213. [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]

Brogli, Heilbronner, et al., 1973
Brogli, F.; Heilbronner, E.; Hornung, V.; Kloster-Jensen, E., 230. Die photoelektronen-spektren methyl-substituierter Acetylene, Helv. Chim. Acta, 1973, 56, 2171. [all data]

Smith, 1967
Smith, W.L., The absorption spectrum of diacetylene in the vacuum ultraviolet, Proc. Roy. Soc. (London), 1967, A300, 519. [all data]

Baker and Turner, Commun. 1967
Baker, C.; Turner, D.W., Photoelectron spectra of acetylene, diacetylene, and their deutero-derivatives, Chem., Commun. 1967, 797. [all data]

Bieri and Asbrink, 1980
Bieri, G.; Asbrink, L., 30.4-nm He(II) photoelectron spectra of organic molecules, J. Electron Spectrosc. Relat. Phenom., 1980, 20, 149. [all data]

Coats and Anderson, 1957
Coats, F.H.; Anderson, R.C., Thermodynamic data from electron-impact measurements on acetylene and substituted acetylenes, J. Am. Chem. Soc., 1957, 79, 1340. [all data]

Pino, Tulej, et al., 2002
Pino, T.; Tulej, M.; Guthe, F.; Pachkov, M.; Maier, J.P., Photodetachment spectroscopy of the C2nH- (n=2-4) anions in the vicinity of their electron detachment threshold, J. Chem. Phys., 2002, 116, 14, 6126-6131, https://doi.org/10.1063/1.1451248 . [all data]

Shi and Ervin, 2000
Shi, Y.; Ervin, K.M., Gas-phase acidity and C-H bond energy of diacetylene, Chem. Phys. Lett., 2000, 318, 1-3, 149-154, https://doi.org/10.1016/S0009-2614(00)00023-3 . [all data]


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