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Gas phase ion energetics data

Go To: Top, References, Notes

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
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 C2H6+ (ion structure unspecified)

Quantity Value Units Method Reference Comment
IE (evaluated)11.52 ± 0.04eVN/AN/AL
Quantity Value Units Method Reference Comment
Proton affinity (review)596.3kJ/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Gas basicity569.9kJ/molN/AHunter and Lias, 1998HL

Ionization energy determinations

IE (eV) Method Reference Comment
11. ± 1.PIAu, Cooper, et al., 1993LL
11.52ESTLuo and Pacey, 1992LL
11.57EIPlessis and Marmet, 1987LBLHLM
11.56 ± 0.02EIPlessis and Marmet, 1987, 2LBLHLM
11.4 ± 0.4EIChatham, Hils, et al., 1984LBLHLM
11.5 ± 0.1EISuzuki and Maeda, 1977LLK
11.56 ± 0.02PEBieri, Burger, et al., 1977LLK
11.76 ± 0.05EIFlesch and Svec, 1973LLK
11.45 ± 0.05TEStockbauer and Inghram, 1971LLK
11.51PEDewar and Worley, 1969RDSH
11.66 ± 0.05EIWilliams and Hamill, 1968RDSH
11.55CICermak, 1968RDSH
11.56PEBaker, Baker, et al., 1968RDSH
11.521 ± 0.007PINicholson, 1965RDSH
11.99PEKimura, Katsumata, et al., 1981Vertical value; LLK
12.0PEBieri and Asbrink, 1980Vertical value; LLK
12.1 ± 0.1PEBieri, Burger, et al., 1977Vertical value; LLK
12.00PEDoucet, Sauvageau, et al., 1975Vertical value; LLK

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
C+43. ± 1.?PIAu, Cooper, et al., 1993LL
C+20.3 ± 0.2CH4+H2EIPlessis and Marmet, 1987, 2LBLHLM
C+29.6 ± 0.2?EISuzuki and Maeda, 1977, 2LLK
CH+31. ± 1.?PIAu, Cooper, et al., 1993LL
CH+20.10 ± 0.08CH3+H2EIPlessis and Marmet, 1987, 2LBLHLM
CH+26.7 ± 0.5?EISuzuki and Maeda, 1977, 2LLK
CH2+25. ± 1.?PIAu, Cooper, et al., 1993LL
CH2+14.69 ± 0.05CH4EIPlessis and Marmet, 1987, 2LBLHLM
CH2+17. ± 2.?EIChatham, Hils, et al., 1984LBLHLM
CH2+17.3 ± 0.15?EISuzuki and Maeda, 1977, 2LLK
CH3+14. ± 1.CH3PIAu, Cooper, et al., 1993LL
CH3+13.65 ± 0.04CH3EIPlessis and Marmet, 1987, 2LBLHLM
CH3+13.56 ± 0.04CH3-EIPlessis and Marmet, 1987, 2LBLHLM
CH3+14. ± 2.CH3EIChatham, Hils, et al., 1984LBLHLM
CH3+14.1 ± 0.1?EISuzuki and Maeda, 1977, 2LLK
CH3+13.46 ± 0.05CH3EIWilliams and Hamill, 1968RDSH
CH4+20.4 ± 0.3?EISuzuki and Maeda, 1977, 2LLK
C2+40. ± 1.?PIAu, Cooper, et al., 1993LL
C2+22.9 ± 0.33H2EIPlessis and Marmet, 1987, 2LBLHLM
C2+31.5 ± 0.2?EISuzuki and Maeda, 1977, 2LLK
C2H+27. ± 1.?PIAu, Cooper, et al., 1993LL
C2H+22.4 ± 0.32H2+HEIPlessis and Marmet, 1987, 2LBLHLM
C2H+25.6 ± 0.2?EISuzuki and Maeda, 1977, 2LLK
C2H2+14. ± 1.2H2PIAu, Cooper, et al., 1993LL
C2H2+14.51 ± 0.042H2EIPlessis and Marmet, 1987, 2LBLHLM
C2H2+15. ± 1.?EIChatham, Hils, et al., 1984LBLHLM
C2H2+14.7 ± 0.1?EISuzuki and Maeda, 1977, 2LLK
C2H2+15.35 ± 0.502H2EID'Or, Collin, et al., 1966RDSH
C2H3+14. ± 1.H2+HPIAu, Cooper, et al., 1993LL
C2H3+13.76 ± 0.08H2+H-EIPlessis and Marmet, 1987, 2LBLHLM
C2H3+14.50 ± 0.04H2+HEIPlessis and Marmet, 1987, 2LBLHLM
C2H3+14.5 ± 0.4H2+HEIChatham, Hils, et al., 1984LBLHLM
C2H3+14.6 ± 0.1H2+HEISuzuki and Maeda, 1977, 2LLK
C2H3+15.22 ± 0.10H2+HEID'Or, Collin, et al., 1966RDSH
C2H4+11. ± 1.H2PIAu, Cooper, et al., 1993LL
C2H4+11.81 ± 0.05H2EIPlessis and Marmet, 1987, 2LBLHLM
C2H4+12.1 ± 0.4H2EIChatham, Hils, et al., 1984LBLHLM
C2H4+12.1 ± 0.1H2PIPECOBombach, Dannacher, et al., 1984T = 0K; LBLHLM
C2H4+12.1 ± 0.1H2EISuzuki and Maeda, 1977, 2LLK
C2H4+12.08 ± 0.03H2PIChupka and Berkowitz, 1967RDSH
C2H4+12.24 ± 0.10H2EID'Or, Collin, et al., 1966RDSH
C2H5+12. ± 1.HPIAu, Cooper, et al., 1993LL
C2H5+12.45 ± 0.008HEIPlessis and Marmet, 1987, 2LBLHLM
C2H5+12.1 ± 0.4HEIChatham, Hils, et al., 1984LBLHLM
C2H5+12.4 ± 0.1HPIPECOBombach, Dannacher, et al., 1984T = 0K; LBLHLM
C2H5+12.40HPITraeger and McLoughlin, 1981LLK
C2H5+12.0 ± 0.1HEISuzuki and Maeda, 1977, 2LLK
C2H5+12.66 ± 0.05HEIWilliams and Hamill, 1968RDSH
C2H5+12.00 ± 0.05H-PIChupka and Berkowitz, 1967RDSH
C2H5+12.65 ± 0.08HPIChupka and Berkowitz, 1967RDSH
H+21. ± 1.?PIAu, Cooper, et al., 1993LL
H+23.5 ± 0.5?EISuzuki and Maeda, 1977, 2LLK
H2+30. ± 1.?PIAu, Cooper, et al., 1993LL
H2+35.0 ± 0.5?EISuzuki and Maeda, 1977, 2LLK
H2+31. ± 1.C2H4+?EINewton, Sciamanna, et al., 1970RDSH
H3+33. ± 1.?PIAu, Cooper, et al., 1993LL
H3+32. ± 1.?EIFuchs, 1972LLK

De-protonation reactions

C2H5- + Hydrogen cation = Ethane

By formula: C2H5- + H+ = C2H6

Quantity Value Units Method Reference Comment
Deltar1758. ± 8.4kJ/molBranDePuy, Gronert, et al., 1989gas phase; B
Deltar1761. ± 8.4kJ/molBranDePuy, Bierbaum, et al., 1984gas phase; B
Quantity Value Units Method Reference Comment
Deltar1723. ± 8.8kJ/molH-TSDePuy, Gronert, et al., 1989gas 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]

Au, Cooper, et al., 1993
Au, J.W.; Cooper, G.; Brion, C.E., The molecular and dissociative photoionization of ethane, propane, and n-butane: Absolute oscillator strengths (10-80 eV) and breakdown pathways, Chem. Phys., 1993, 173, 241. [all data]

Luo and Pacey, 1992
Luo, Y.-R.; Pacey, P.D., Effects of alkyl substitution on ionization energies of alkanes and haloalkanes and on heats of formation of their molecular cations. Part 2. Alkanes and chloro-, bromo- and iodoalkanes, Int. J. Mass Spectrom. Ion Processes, 1992, 112, 63. [all data]

Plessis and Marmet, 1987
Plessis, P.; Marmet, P., Electroionization study of ethane: structures in the ionization and appearance energy curves, Can. J. Chem., 1987, 65, 2004. [all data]

Plessis and Marmet, 1987, 2
Plessis, P.; Marmet, P., Electroionization study of ethane: Ionization and appearance energies, ion-pair formations and negative ions, Can. J. Chem., 1987, 65, 1424. [all data]

Chatham, Hils, et al., 1984
Chatham, H.; Hils, D.; Robertson, R.; Gallagher, A., Total and partial electron collisional ionization cross sections for CH4, C2H6, SiH4, and Si2H6, J. Chem. Phys., 1984, 81, 1770. [all data]

Suzuki and Maeda, 1977
Suzuki, I.H.; Maeda, K., Ionization efficiency curves of ethane by electron impact, Int. J. Mass Spectrom. Ion Phys., 1977, 24, 147. [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]

Flesch and Svec, 1973
Flesch, G.D.; Svec, H.J., Fragmentation reactions in the mass spectrometer for C2-C5 alkanes, J. Chem. Soc. Faraday Trans. 2, 1973, 69, 1187. [all data]

Stockbauer and Inghram, 1971
Stockbauer, R.; Inghram, M.G., Experimental relative Franck-Condon factors for the ionization of methane, ethane, and propane, J. Chem. Phys., 1971, 54, 2242. [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]

Williams and Hamill, 1968
Williams, J.M.; Hamill, W.H., Ionization potentials of molecules and free radicals and appearance potentials by electron impact in the mass spectrometer, J. Chem. Phys., 1968, 49, 4467. [all data]

Cermak, 1968
Cermak, V., Penning ionization electron spectroscopy, Advan. Mass Spectrom., 1968, 4, 697. [all data]

Baker, Baker, et al., 1968
Baker, A.D.; Baker, C.; Brundle, C.R.; Turner, D.W., The electronic structures of methane, ethane, ethylene and formaldehyde studied by high-resolution molecular photoelectron spectroscopy, Intern. J. Mass Spectrom. Ion Phys., 1968, 1, 285. [all data]

Nicholson, 1965
Nicholson, A.J.C., Photoionization-efficiency curves. II. False and genuine structure, J. Chem. Phys., 1965, 43, 1171. [all data]

Kimura, Katsumata, et al., 1981
Kimura, K.; Katsumata, S.; Achiba, Y.; Yamazaki, T.; Iwata, S., Ionization energies, Ab initio assignments, and valence electronic structure for 200 molecules in Handbook of HeI Photoelectron Spectra of Fundamental Organic Compounds, Japan Scientific Soc. Press, Tokyo, 1981. [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]

Doucet, Sauvageau, et al., 1975
Doucet, J.; Sauvageau, P.; Sandorfy, C., Photoelectron far-ultraviolet absorption spectra of chlorofluoro derivatives of ethane, J. Chem. Phys., 1975, 62, 355. [all data]

Suzuki and Maeda, 1977, 2
Suzuki, I.H.; Maeda, K., Behavior of hydrogen atoms in the fragmentation of CH3CD3, Can. J. Chem., 1977, 55, 3124. [all data]

D'Or, Collin, et al., 1966
D'Or, L.; Collin, J.E.; Longree, J., Ionisation et dissociation de l'ethane sous l'impact electronique. Spectres de masse et phenomenes d'echange dans C2H6, C2H5D, CH3CD3 et C2D6, Bull. Classe Sci. Acad. Roy. Belg., 1966, 52, 518. [all data]

Bombach, Dannacher, et al., 1984
Bombach, R.; Dannacher, J.; Stadelmann, J.-P., The rate/energy functions for the competitive fragmentation processes of ethylene and ethane cations, Int. J. Mass Spectrom. Ion Processes, 1984, 58, 217. [all data]

Chupka and Berkowitz, 1967
Chupka, W.A.; Berkowitz, J., Photoionization of ethane, propane, and n-butane with mass analysis, J. Chem. Phys., 1967, 47, 2921. [all data]

Traeger and McLoughlin, 1981
Traeger, J.C.; McLoughlin, R.G., Absolute heats of formation for gas phase cations, J. Am. Chem. Soc., 1981, 103, 3647. [all data]

Newton, Sciamanna, et al., 1970
Newton, A.S.; Sciamanna, A.F.; Thomas, G.E., The occurrence of the H3+ ion in the mass spectra of organic compounds, Intern. J. Mass Spectrom. Ion Phys., 1970, 5, 465. [all data]

Fuchs, 1972
Fuchs, R., Die kinetische energie ionisierter molekulfragmente VII. H3 ALS fragmention bei der elektronenstrossionisierung von kohlenwasserstoffen, Int. J. Mass Spectrom. Ion Processes, 1972, 8, 193. [all data]

DePuy, Gronert, et al., 1989
DePuy, C.H.; Gronert, S.; Barlow, S.E.; Bierbaum, V.M.; Damrauer, R., The Gas Phase Acidities of the Alkanes, J. Am. Chem. Soc., 1989, 111, 6, 1968, https://doi.org/10.1021/ja00188a003 . [all data]

DePuy, Bierbaum, et al., 1984
DePuy, C.H.; Bierbaum, V.M.; Damrauer, R., Relative Gas-Phase Acidities of the Alkanes, J. Am. Chem. Soc., 1984, 106, 4051. [all data]


Go To: Top, Gas phase ion energetics data, References