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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
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
LL - Sharon G. Lias and Joel F. Liebman

View reactions leading to C2H2+ (ion structure unspecified)

Quantity Value Units Method Reference Comment
IE (evaluated)11.400 ± 0.002eVN/AN/AL
Quantity Value Units Method Reference Comment
Proton affinity (review)641.4kJ/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Gas basicity616.7kJ/molN/AHunter and Lias, 1998HL

Ionization energy determinations

IE (eV) Method Reference Comment
11.41 ± 0.01EIPlessis and Marmet, 1986LBLHLM
11.40PIHayaishi, Iwata, et al., 1982LBLHLM
11.4EVALRosmus, Botschwina, et al., 1981LLK
11.40PEKimura, Katsumata, et al., 1981LLK
11.40PEBieri, Schmelzer, et al., 1980LLK
11.4 ± 0.1EISuzuki and Maeda, 1978LLK
11.4 ± 0.1EISuzuki and Maeda, 1977LLK
11.40 ± 0.02PEBieri, Burger, et al., 1977LLK
~11.3EIVan Veen and Plantenga, 1976LLK
11.37 ± 0.05EIReeher, Flesch, et al., 1976LLK
11.403 ± 0.0003PECarlier, Dubois, et al., 1975LLK
11.394 ± 0.005PIParr and Taylor, 1973LLK
11.398 ± 0.005PIDibeler and Walker, 1973LLK
11.40PEBrogli, Heilbronner, et al., 1973LLK
11.39 ± 0.02EILossing, 1970RDSH
11.395 ± 0.015PIOmura, Kaneko, et al., 1969RDSH
11.39 ± 0.05EIWilliams and Hamill, 1968RDSH
11.41 ± 0.01EICollins, Winters, et al., 1968RDSH
11.40 ± 0.01PEBaker and Turner, 1968RDSH
11.400 ± 0.005PIBrehm, 1966RDSH
11.396 ± 0.003PINicholson, 1965RDSH
11.40 ± 0.02EIMelton and Hamill, 1964RDSH
11.406 ± 0.006PIDibeler and Reese, 1964RDSH
11.41 ± 0.01PIWatanabe and Namioka, 1956RDSH
11.2 ± 0.1EIKusch, Hustrulid, et al., 1937RDSH
11.41SPrice, 1935RDSH
11.49PEBieri and Asbrink, 1980Vertical value; LLK
11.43PECavell and Allison, 1978Vertical value; LLK

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
C+21.20 ± 0.05CH2EILocht and Davister, 1995LL
C+24. ± 1.?PICooper, Ibuki, et al., 1988LL
C+20.43 ± 0.05CH2EIPlessis and Marmet, 1986LBLHLM
C+22.5 ± 0.3C+2HEISuzuki and Maeda, 1977LLK
C+23.6?EIBloch, 1963RDSH
C+24.5 ± 1.0C+2HEIKusch, Hustrulid, et al., 1937RDSH
CH+20.85 ± 0.05CHEIDavister and Locht, 1995LL
CH+20.54 ± 0.05CHEIPlessis and Marmet, 1986LBLHLM
CH+23.9 ± 0.2C+HEIPlessis and Marmet, 1986LBLHLM
CH+24.1C+HPIHayaishi, Iwata, et al., 1982LBLHLM
CH+20.7 ± 0.1CHPIHayaishi, Iwata, et al., 1982LBLHLM
CH+20.9 ± 0.2CHEISuzuki and Maeda, 1977LLK
CH+21.5 ± 0.2CHEIKloster-Jensen, Pascual, et al., 1970RDSH
CH+21.9CHEIHaney and Franklin, 1968RDSH
CH+22.2 ± 0.5CHEIKusch, Hustrulid, et al., 1937RDSH
CH2+19.74 ± 0.20CEILocht and Davister, 1995LL
CH2+18.17 ± 0.09C-EIPlessis and Marmet, 1986LBLHLM
CH2+19.40 ± 0.12CEIPlessis and Marmet, 1986LBLHLM
CH2+19.4 ± 0.1CPIHayaishi, Iwata, et al., 1982LBLHLM
CH2+20.5 ± 0.2?EISuzuki and Maeda, 1977LLK
CH2+21.CEIFranklin and Munson, 1965RDSH
C2+19. ± 1.H2CIELReid, Ballantine, et al., 1995LL
C2+18.44 ± 0.07H2EILocht and Davister, 1995LL
C2+22.60 ± 0.122HEIPlessis and Marmet, 1986LBLHLM
C2+18.16 ± 0.05H2EIPlessis and Marmet, 1986LBLHLM
C2+18.1 ± 0.1H2PIHayaishi, Iwata, et al., 1982LBLHLM
C2+22.7 ± 0.12HPIHayaishi, Iwata, et al., 1982LBLHLM
C2+19.2 ± 0.2?EISuzuki and Maeda, 1977LLK
C2+23.62H?EIMomigny and Derouane, 1968RDSH
C2+19.5H2EIBloch, 1963RDSH
C2+23.82H?EIBloch, 1963RDSH
C2+22.72H?EIField, Franklin, et al., 1957RDSH
C2+18.2H2EIField, Franklin, et al., 1957RDSH
C2+23.3 ± 0.52H?EICoats and Anderson, 1957RDSH
C2+23.8 ± 0.32HEIKusch, Hustrulid, et al., 1937RDSH
C2H+17.35 ± 0.04HPIPECOServais and Locht, 1995LL
C2H+17.360HPIPECOWeitzel, Mahnert, et al., 1994LL
C2H+17.30 ± 0.08HEIDavister and Locht, 1994LL
C2H+17.33 ± 0.05HPIPECONorwood and Ng, 1989LL
C2H+16.70 ± 0.10HEIPlessis and Marmet, 1986LBLHLM
C2H+16.8 ± 0.1HPIHayaishi, Iwata, et al., 1982LBLHLM
C2H+16.79 ± 0.03HPIOno and Ng, 1981LLK
C2H+17.3HPIPECOEland, 1979LLK
C2H+17.5 ± 0.1HEISuzuki and Maeda, 1977LLK
C2H+17.36 ± 0.01HPIDibeler, Walker, et al., 1973LLK
C2H+17.22HPIBotter, Dibeler, et al., 1966RDSH
C2H+17.3HEIField, Franklin, et al., 1957RDSH
C2H+17.8 ± 0.2HEIKusch, Hustrulid, et al., 1937RDSH
H+18.83 ± 0.23C2HEIDavister and Locht, 1994LL
H+23. ± 1.?PICooper, Ibuki, et al., 1988LL
H+19.35 ± 0.05C2HPIShiromaru, Achiba, et al., 1987LBLHLM
H+20.6 ± 0.3?EISuzuki and Maeda, 1977LLK
H+21.7 ± 1.0C2+HEIKusch, Hustrulid, et al., 1937RDSH
H+25.6 ± 1.0CH+CEIKusch, Hustrulid, et al., 1937RDSH

De-protonation reactions

C2H- + Hydrogen cation = Acetylene

By formula: C2H- + H+ = C2H2

Quantity Value Units Method Reference Comment
Deltar1580. ± 20.kJ/molAVGN/AAverage of 8 values; Individual data points
Quantity Value Units Method Reference Comment
Deltar1550. ± 20.kJ/molAVGN/AAverage of 7 values; Individual data points


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]

Plessis and Marmet, 1986
Plessis, P.; Marmet, P., Electroionization study of acetylene and fragment ions, Int. J. Mass Spectrom. Ion Processes, 1986, 70, 23. [all data]

Hayaishi, Iwata, et al., 1982
Hayaishi, T.; Iwata, S.; Sasanuma, M.; Ishiguro, E.; Morioka, Y.; Iida, Y.; Nakamura, M., Photoionisation mass spectrometric study of acetylene in the VUV region, J. Phys. B:, 1982, 15, 79. [all data]

Rosmus, Botschwina, et al., 1981
Rosmus, P.; Botschwina, P.; Maier, J.P., On the ionic states of vinylidene and acetylene, Chem. Phys. Lett., 1981, 84, 71. [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, 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]

Suzuki and Maeda, 1978
Suzuki, I.H.; Maeda, K., Ionization efficiency curves of acetylene by mono-energetic electron impact, Adv. Mass Spectrom., 1978, 7, 182. [all data]

Suzuki and Maeda, 1977
Suzuki, I.H.; Maeda, K., Ionization efficiency curves of acetylene by electron impact, Mass Spectrosc. (Tokyo), 1977, 25, 223. [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]

Van Veen and Plantenga, 1976
Van Veen, E.H.; Plantenga, F.L., Low-energy electron-impact excitation spectra of acetylene, Chem. Phys. Lett., 1976, 38, 493. [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]

Carlier, Dubois, et al., 1975
Carlier, P.; Dubois, J.E.; Masclet, P.; Mouvier, G., Spectres de photoelectrons des alcynes, J. Electron Spectrosc. Relat. Phenom., 1975, 7, 55. [all data]

Parr and Taylor, 1973
Parr, G.R.; Taylor, J.W., A photoionization mass spectrometer utilizing a high intensity molecular beam sampling system and synchrotron radiation, Rev. Sci. Instrum., 1973, 44, 1578. [all data]

Dibeler and Walker, 1973
Dibeler, V.H.; Walker, J.A., Photoionization of acetylene near threshold, Int. J. Mass Spectrom. Ion Phys., 1973, 11, 49. [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]

Lossing, 1970
Lossing, F.P., Threshold ionization of acetylene by monoenergetic electron impact, Intern. J. Mass Spectrom. Ion Phys., 1970, 5, 190. [all data]

Omura, Kaneko, et al., 1969
Omura, I.; Kaneko, T.; Yamada, Y.; Tanaka, K., Mass spectrometric studies of photoionization. IV. Acetylene and propyne, J. Phys. Soc. Japan, 1969, 27, 178. [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]

Collins, Winters, et al., 1968
Collins, J.H.; Winters, R.E.; Engerholm, G.G., Fine structure in energy-distribution-difference ionizationefficiency curves, J. Chem. Phys., 1968, 49, 2469. [all data]

Baker and Turner, 1968
Baker, C.; Turner, D.W., High resolution molecular photoelectron spectroscopy. III.Acetylenes and azaacetylenes, Proc. Roy. Soc. (London), 1968, A308, 19. [all data]

Brehm, 1966
Brehm, B., Massenspektrometrische Untersuchung der Photoionisation von Molekulen, Z. Naturforsch., 1966, 21a, 196. [all data]

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

Melton and Hamill, 1964
Melton, C.E.; Hamill, W.H., Appearance potentials by the retarding potential-difference method for secondary ions produced by excited-neutral, excited ion-neutral, and ion-neutral reactions, J. Chem. Phys., 1964, 41, 1469. [all data]

Dibeler and Reese, 1964
Dibeler, V.H.; Reese, R.M., Mass spectrometric study of photoionization. I. Apparatus and initial observations on acetylene, acetylene-d2, benzene, and benzene-d6, J. Res. NBS, 1964, 68A, 409. [all data]

Watanabe and Namioka, 1956
Watanabe, K.; Namioka, T., Ionization potential of propyne, J. Chem. Phys., 1956, 24, 915. [all data]

Kusch, Hustrulid, et al., 1937
Kusch, P.; Hustrulid, A.; Tate, J.T., The dissociation of HCN, C2H2, C2N2 and C2H4 by electron impact, Phys. Rev., 1937, 52, 843. [all data]

Price, 1935
Price, W.C., The absorption spectra of acetylene, ethylene, and ethane in the far ultraviolet, Phys. Rev., 1935, 47, 444. [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]

Cavell and Allison, 1978
Cavell, R.G.; Allison, D.A., Photoelectron spectra of acetylene with He(I), He(II) , Zr M175»{zeta}, MgK»«alpha» radiation sources, J. Chem. Phys., 1978, 69, 159. [all data]

Locht and Davister, 1995
Locht, R.; Davister, M., The dissociative ionization of C2H2. The C+, C2+, and CH2+ dissociation channels. The vinylidene ion as a transient?, Chem. Phys., 1995, 195, 443. [all data]

Cooper, Ibuki, et al., 1988
Cooper, G.; Ibuki, T.; Iida, Y.; Brion, C.E., Absolute dipole oscillator strengths for photoabsorption and the molecular and dissociative photoionization of acetylene, Chem. Phys., 1988, 125, 307. [all data]

Bloch, 1963
Bloch, A., Mass spectra of acetylene under high pressure in the ion source, Advan. Mass Spectrom., 1963, 2, 48. [all data]

Davister and Locht, 1995
Davister, M.; Locht, R., The dissociative ionization of C2H2 and C2D2. The [CH(CD)]+ dissociation channel. The H(D)C«equiv»C(D)H binding energy, Chem. Phys., 1995, 191, 333. [all data]

Kloster-Jensen, Pascual, et al., 1970
Kloster-Jensen, E.; Pascual, C.; Vogt, J., Mass spectrometric studies of mono- and di-haloacetylenes,, Helv. Chim. Acta, 1970, 53, 2109. [all data]

Haney and Franklin, 1968
Haney, M.A.; Franklin, J.L., Correlation of excess energies of electron-impact dissociations with the translational energies of the products, J.Chem. Phys., 1968, 48, 4093. [all data]

Franklin and Munson, 1965
Franklin, J.L.; Munson, M.S.B., Ion-molecule reactions in methane-oxygen and acetylene-oxygen systems, Symp. Combust., 10th, Univ. Cambridge, Cambridge, Engl.,, 1965, 1964, 561. [all data]

Reid, Ballantine, et al., 1995
Reid, C.J.; Ballantine, J.A.; Andrews, S.R.; Harris, F.M., Charge inversion of ground-state and metastable-state C2+ cations formed from electroionised C2H2 and C2N2, and a re-evaluation of the carbon dimer's ionisation energy, Chem. Phys., 1995, 190, 113. [all data]

Momigny and Derouane, 1968
Momigny, J.; Derouane, E., Fine structure in the first derivative of ionization curves obtained under electron impact, Advan. Mass Spectrom., 1968, 4, 607. [all data]

Field, Franklin, et al., 1957
Field, F.H.; Franklin, J.L.; Lampe, F.W., Reactions of gaseous ions. II. Acetylene, J. Am. Chem. Soc., 1957, 79, 2665. [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]

Servais and Locht, 1995
Servais, C.; Locht, R., The appearance energy of C2H+ from C2H2 revisited. A photoion-photoelectron coincidence spectroscopic determination, Chem. Phys. Lett., 1995, 236, 96. [all data]

Weitzel, Mahnert, et al., 1994
Weitzel, K.-M.; Mahnert, J.; Penno, M., ZEKE-PEPICO investigations of dissociation energies in ionic reactions, Chem. Phys. Lett., 1994, 224, 371. [all data]

Davister and Locht, 1994
Davister, M.; Locht, R., The dissociative electroionization of C2H2, C2D2 and C2HD. Investigation of the [C2H(D)]+ and [H(D)]+ dissociation channels. The (D)H-C2H(D) binding energy, Chem. Phys., 1994, 189, 805. [all data]

Norwood and Ng, 1989
Norwood, K.; Ng, C.Y., A state-selected study of the unimolecular decompoisition of C2H2+(A,B) using the photoion photoelectron coincidence method, J. Chem. Phys., 1989, 91, 2898. [all data]

Ono and Ng, 1981
Ono, Y.; Ng, C.Y., The heat of formation of C2H+, J. Chem. Phys., 1981, 74, 6985. [all data]

Eland, 1979
Eland, J.H.D., Dissociations of state-selected C2H2+, H2S+ and D2S+ ions studied by photoelectron-photoion coincidence spectroscopy, Int. J. Mass Spectrom. Ion Phys., 1979, 31, 161. [all data]

Dibeler, Walker, et al., 1973
Dibeler, V.H.; Walker, J.A.; McCulloh, K.E., Observations on hot bands in the molecular and dissociative photoionization of acetylene and the heat of formation of the ethynyl ion, J. Chem. Phys., 1973, 59, 2264. [all data]

Botter, Dibeler, et al., 1966
Botter, R.; Dibeler, V.H.; Walker, J.A.; Rosenstock, H.M., Experimental and theoretical studies of photoionization-efficiency curves for C2H2 and C2D2, J. Chem. Phys., 1966, 44, 1271. [all data]

Shiromaru, Achiba, et al., 1987
Shiromaru, H.; Achiba, Y.; Kimura, K.; Lee, Y.T., Determination of the C-H bond dissociation energies of ethylene and acetylene by observation of the threshold energies of H+ formation by synchrotron radiation, J. Phys. Chem., 1987, 91, 17. [all data]


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