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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

View reactions leading to C2H4O+ (ion structure unspecified)

Quantity Value Units Method Reference Comment
IE (evaluated)10.229 ± 0.0007eVN/AN/AL
Quantity Value Units Method Reference Comment
Proton affinity (review)768.5kJ/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Gas basicity736.5kJ/molN/AHunter and Lias, 1998HL

Electron affinity determinations

EA (eV) Method Reference Comment
0.00035EFDDesfrancois, Abdoul-Carime, et al., 1994EA: 0.36 meV. Dipole-bound state.; B

Ionization energy determinations

IE (eV) Method Reference Comment
10.22PITraeger, 1985LBLHLM
10.22PITraeger, McLouglin, et al., 1982LBLHLM
10.14 ± 0.02EIEl-Sherbini, Allam, et al., 1981LLK
10.22PIJochims, Lohr, et al., 1978LLK
10.20PIStaley, Wieting, et al., 1977LLK
10.227 ± 0.005PEHernandez, Masclet, et al., 1977LLK
10.23EIHolmes, Terlouw, et al., 1976LLK
10.20PEMeeks, Arnett, et al., 1975LLK
10.20PEMcGlynn and Meeks, 1975LLK
10.20 ± 0.02PIWarneck, 1974LLK
10.21PETam, Yee, et al., 1974LLK
10.19SOgata, Kitayama, et al., 1974LLK
10.22 ± 0.01PIKrassig, Reinke, et al., 1974LLK
10.2298 ± 0.0007PIKnowles and Nicholson, 1974LLK
10.24 ± 0.02PEChadwick and Katrib, 1974LLK
10.22 ± 0.01PIPotapov and Sorokin, 1972LLK
10.22 ± 0.01PECocksey, Eland, et al., 1971LLK
10.20 ± 0.02PIMatthews and Warneck, 1969RDSH
10.20PEDewar and Worley, 1969RDSH
10.22 ± 0.01PIPotapov, Filyugina, et al., 1968RDSH
10.20 ± 0.03PIVilesov, 1960RDSH
10.25 ± 0.03PIHurzeler, Inghram, et al., 1958RDSH
10.21 ± 0.01PIWatanabe, 1957RDSH
10.20 ± 0.03PIVilesov and Terenin, 1957RDSH
10.2291 ± 0.0007SWalsh, 1946RDSH
10.24PIPECOJohnson, Powis, et al., 1982Vertical value; LBLHLM
10.3PEBieri, Asbrink, et al., 1982Vertical value; LBLHLM
10.23PEBenoit and Harrison, 1977Vertical value; LLK
10.9PERao, 1975Vertical value; LLK
10.26PEKimura, Katsumata, et al., 1975Vertical value; LLK

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
CHO+11.78CH3PITraeger, 1985LBLHLM
CHO+11.79 ± 0.03CH3PIWarneck, 1974LLK
CHO+11.79 ± 0.03CH3PIMatthews and Warneck, 1969RDSH
CH2+15.08 ± 0.09?PIKrassig, Reinke, et al., 1974LLK
CH3+13.9 ± 0.1CHOPIPECOBombach, Stadelmann, et al., 1981LLK
CH3+14.08CO+HPIJochims, Lohr, et al., 1978LLK
CH3+14.11 ± 0.05CO+HPIWarneck, 1974LLK
CH3+14.08 ± 0.05CO+HPIKrassig, Reinke, et al., 1974LLK
CH3+14.53CHO?EIHaney and Franklin, 1969RDSH
CH4+12.61COPIJochims, Lohr, et al., 1978LLK
CH4+12.61 ± 0.06COPIKrassig, Reinke, et al., 1974LLK
CO+14.0 ± 0.1CH4EIShigorin, Filyugina, et al., 1966RDSH
CO+13.9 ± 0.1CH4EIDorman, 1965RDSH
C2H2O+13.06 ± 0.09H2?PIKrassig, Reinke, et al., 1974LLK
C2H2O+10.7 ± 0.1H2EIShigorin, Filyugina, et al., 1966RDSH
C2H3+14.17 ± 0.13OHPIKrassig, Reinke, et al., 1974LLK
C2H3O+10.67HPITraeger, McLouglin, et al., 1982LBLHLM
C2H3O+11.0 ± 0.1HEIBurgers and Holmes, 1982LBLHLM
C2H3O+10.50 ± 0.05HPIPECOBombach, Stadelmann, et al., 1981LLK
C2H3O+10.90HPIJochims, Lohr, et al., 1978LLK
C2H3O+10.82HPIStaley, Wieting, et al., 1977LLK
C2H3O+10.82 ± 0.03HPIWarneck, 1974LLK
C2H3O+10.90 ± 0.03HPIKrassig, Reinke, et al., 1974LLK
C2H3O+10.89 ± 0.03HPIPotapov and Sorokin, 1972LLK
C2H3O+10.89HPIPotapov, Filyugina, et al., 1968RDSH
C2H3O+10.75 ± 0.08HEIShigorin, Filyugina, et al., 1966RDSH
C2H3O+10.5 ± 0.2HEIDorman, 1965RDSH

De-protonation reactions

C2H3O- + Hydrogen cation = Acetaldehyde

By formula: C2H3O- + H+ = C2H4O

Quantity Value Units Method Reference Comment
Δr1533.1 ± 3.4kJ/molD-EAMead, Lykke, et al., 1984gas phase; Uncertainty: 6 millical/mol (0.26 micro-eV).Dipolebound state at ca. 14.3 cal/mol (5 cm-1); B
Δr1531. ± 9.2kJ/molG+TSBartmess, Scott, et al., 1979gas phase; Acid: ethanal. The enol is 9.6 kcal/mol more acidic: Holmes and Lossing, 1982; value altered from reference due to change in acidity scale; B
Δr1533. ± 12.kJ/molG+TSCumming and Kebarle, 1978gas phase; B
Quantity Value Units Method Reference Comment
Δr1505. ± 5.0kJ/molH-TSMead, Lykke, et al., 1984gas phase; Uncertainty: 6 millical/mol (0.26 micro-eV).Dipolebound state at ca. 14.3 cal/mol (5 cm-1); B
Δr1502. ± 8.4kJ/molIMREBartmess, Scott, et al., 1979gas phase; Acid: ethanal. The enol is 9.6 kcal/mol more acidic: Holmes and Lossing, 1982; value altered from reference due to change in acidity scale; B
Δr1505. ± 8.4kJ/molIMRECumming and Kebarle, 1978gas phase; B

C2H3O- + Hydrogen cation = Acetaldehyde

By formula: C2H3O- + H+ = C2H4O

Quantity Value Units Method Reference Comment
Δr1645.1 ± 4.0kJ/molD-EANimlos, Soderquist, et al., 1989gas phase; B
Δr1636. ± 8.8kJ/molG+TSDePuy, Bierbaum, et al., 1985gas phase; B
Δr1619. ± 33.kJ/molCIDTGraul and Squires, 1990gas phase; B
Δr<1598.3kJ/molCIDTGraul and Squires, 1988gas phase; B
Quantity Value Units Method Reference Comment
Δr1613. ± 4.6kJ/molH-TSNimlos, Soderquist, et al., 1989gas phase; B
Δr1604. ± 8.4kJ/molIMRBDePuy, Bierbaum, et al., 1985gas phase; B
Δr<1565.9 ± 2.5kJ/molH-TSGraul and Squires, 1988gas 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, . [all data]

Desfrancois, Abdoul-Carime, et al., 1994
Desfrancois, C.; Abdoul-Carime, H.; Khelifa, N.; Schermann, J.P., Fork 1/r to 1/r2 Potentials: Electron Exchange between Rydberg Atoms and Polar Molecules, Phys. Rev. Lett., 1994, 73, 18, 2436, . [all data]

Traeger, 1985
Traeger, J.C., Heat of formation for the formyl cation by photoionization mass spectrometry, Int. J. Mass Spectrom. Ion Processes, 1985, 66, 271. [all data]

Traeger, McLouglin, et al., 1982
Traeger, J.C.; McLouglin, R.G.; Nicholson, A.J.C., Heat of formation for acetyl cation in the gas phase, J. Am. Chem. Soc., 1982, 104, 5318. [all data]

El-Sherbini, Allam, et al., 1981
El-Sherbini, T.M.; Allam, S.H.; Migahed, M.D.; Dawoud, A.M., Mass spectrometric investigation of aliphatic aldehydes, Z. Naturforsch. A:, 1981, 36, 1334. [all data]

Jochims, Lohr, et al., 1978
Jochims, H.-W.; Lohr, W.; Baumgartel, H., Photoionization mass spectrometry studies of deuterated acetaldehydes CH3CDO and CD3CHO, Chem. Phys. Lett., 1978, 54, 594. [all data]

Staley, Wieting, et al., 1977
Staley, R.H.; Wieting, R.D.; Beauchamp, J.L., Carbenium ion stabilities in the gas phase and solution. An ion cyclotron resonance study of bromide transfer reactions involving alkali ions, alkyl carbenium ions, acyl cations and cyclic halonium ions, J. Am. Chem. Soc., 1977, 99, 5964. [all data]

Hernandez, Masclet, et al., 1977
Hernandez, R.; Masclet, P.; Mouvier, G., Spectroscopie de photoelectrons d'aldehydes et de cetones aliphatiques, J. Electron Spectrosc. Relat. Phenom., 1977, 10, 333. [all data]

Holmes, Terlouw, et al., 1976
Holmes, J.L.; Terlouw, J.K.; Lossing, F.P., The thermochemistry of C2H4O+ ions, J. Phys. Chem., 1976, 80, 2860. [all data]

Meeks, Arnett, et al., 1975
Meeks, J.L.; Arnett, J.F.; Larson, D.; McGlynn, S.P., Photoelectron spectroscopy of carbonyls. Ionization assignments, Chem. Phys. Lett., 1975, 30, 190. [all data]

McGlynn and Meeks, 1975
McGlynn, S.P.; Meeks, J.L., Photoelectron spectra of carbonyls: Acetaldehyde, acetamide, biacetyl, pyruvic acid, methyl pyruvate and vamide, J. Electron Spectrosc. Relat. Phenom., 1975, 6, 269. [all data]

Warneck, 1974
Warneck, P., Heat of formation of the HCO radical, Z. Naturforsch. A:, 1974, 29, 350. [all data]

Tam, Yee, et al., 1974
Tam, W.-C.; Yee, D.; Brion, C.E., Photoelectron spectra of some aldehydes and ketones, J. Electron Spectrosc. Relat. Phenom., 1974, 4, 77. [all data]

Ogata, Kitayama, et al., 1974
Ogata, H.; Kitayama, J.; Koto, M.; Kojima, S.; Nihei, Y.; Kamada, H., Vacuum ultraviolet absorption and photoelectron spectra of aliphatic ketones, Bull. Chem. Soc. Jpn., 1974, 47, 958. [all data]

Krassig, Reinke, et al., 1974
Krassig, R.; Reinke, D.; Baumgartel, H., Photo-reaktionen kleiner organischer molekule II. Die photoionenspektren der Isomeren propylen-cyclopropan und acetaldehyd-athylenoxyd, Ber. Bunsen-Ges. Phys. Chem., 1974, 78, 425. [all data]

Knowles and Nicholson, 1974
Knowles, D.J.; Nicholson, A.J.C., Ionization energies of formic and acetic acid monomers, J. Chem. Phys., 1974, 60, 1180. [all data]

Chadwick and Katrib, 1974
Chadwick, D.; Katrib, A., Photoelectron spectra of acetaldehyde and acetyl halides, J. Electron Spectrosc. Relat. Phenom., 1974, 3, 39. [all data]

Potapov and Sorokin, 1972
Potapov, V.K.; Sorokin, V.V., Kinetic energies of products of dissociative photoionization of molecules. I. Aliphatic ketones and alcohols, Khim. Vys. Energ., 1972, 6, 387. [all data]

Cocksey, Eland, et al., 1971
Cocksey, B.J.; Eland, J.H.D.; Danby, C.J., The effect of alkyl substitution on ionisation potential, J. Chem. Soc., 1971, (B), 790. [all data]

Matthews and Warneck, 1969
Matthews, C.S.; Warneck, P., Heats of formation of CHO+ and C3H3+ by photoionization, J. Chem. Phys. 5, 1969, 1, 854. [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]

Potapov, Filyugina, et al., 1968
Potapov, V.K.; Filyugina, A.D.; Shigorin, D.N.; Ozerova, G.A., Photoionization of some compounds containing the carbonyl and amino groups, Dokl. Akad. Nauk SSSR, 1968, 180, 398, In original 352. [all data]

Vilesov, 1960
Vilesov, F.I., The photoionization of vapors of compounds whose molecules contain carbonyl groups, Dokl. Phys. Chem., 1960, 132, 521, In original 1332. [all data]

Hurzeler, Inghram, et al., 1958
Hurzeler, H.; Inghram, M.G.; Morrison, J.D., Photon impact studies of molecules using a mass spectrometer, J. Chem. Phys., 1958, 28, 76. [all data]

Watanabe, 1957
Watanabe, K., Ionization potentials of some molecules, J. Chem. Phys., 1957, 26, 542. [all data]

Vilesov and Terenin, 1957
Vilesov, F.I.; Terenin, A.N., The photoionization of the vapors of certain organic compounds, Dokl. Akad. Nauk SSSR, 1957, 115, 744, In original 539. [all data]

Walsh, 1946
Walsh, A.D., The absorption spectrum of acetaldehyde in the vacuum ultra-violet, Proc. Roy. Soc. (London), 1946, A185, 176. [all data]

Johnson, Powis, et al., 1982
Johnson, K.; Powis, I.; Danby, C.J., A photoelectron-photoion coincidence study of acetaldehyde and ethylene oxide molecular ions, Chem. Phys., 1982, 70, 329. [all data]

Bieri, Asbrink, et al., 1982
Bieri, G.; Asbrink, L.; Von Niessen, W., 30.4-nm He(II) photoelectron spectra of organic molecules, J. Electron Spectrosc. Relat. Phenom., 1982, 27, 129. [all data]

Benoit and Harrison, 1977
Benoit, F.M.; Harrison, A.G., Predictive value of proton affinity. Ionization energy correlations involving oxygenated molecules, J. Am. Chem. Soc., 1977, 99, 3980. [all data]

Rao, 1975
Rao, C.N.R., Lone-pair ionization bands of chromophores in the photoelectron spectra of organic molecules, Indian J. Chem., 1975, 13, 950. [all data]

Kimura, Katsumata, et al., 1975
Kimura, K.; Katsumata, S.; Yamazaki, T.; Wakabayashi, H., UV photoelectron spectra and sum rule consideration; out-of-plane orbitals of unsaturated compounds with planar-skeleton structure, J. Electron Spectrosc. Relat. Phenom., 1975, 6, 41. [all data]

Bombach, Stadelmann, et al., 1981
Bombach, R.; Stadelmann, J.P.; Vogt, J., The fragmentation and isomerization of internal energy selected acetaldehyde molecular cations, Chem. Phys., 1981, 60, 293. [all data]

Haney and Franklin, 1969
Haney, M.A.; Franklin, J.L., Excess energies in mass spectra of some oxygen-containing organic compounds, J. Chem. Soc. Faraday Trans., 1969, 65, 1794. [all data]

Shigorin, Filyugina, et al., 1966
Shigorin, D.N.; Filyugina, A.D.; Potapov, V.K., Ionization and dissociation of molecules of acetaldehyde, acetone, and acetic acid on electron impact, Teor. i Eksperim. Khim., 1966, 2, 554, In original 417. [all data]

Dorman, 1965
Dorman, F.H., Fragment ions from CH3CHO and (CH3)2CO by electron impact, J. Chem. Phys., 1965, 42, 65. [all data]

Burgers and Holmes, 1982
Burgers, P.C.; Holmes, J.L., Metastable ion studies. XIII. The measurement of appearance energies of metastable peaks, Org. Mass Spectrom., 1982, 17, 123. [all data]

Mead, Lykke, et al., 1984
Mead, R.D.; Lykke, K.R.; Lineberger, W.C.; Marks, J.; Brauman, J.I., Spectroscopy and Dynamics of the Dipole-Bound State of Acetaldehyde Enolate., J. Chem. Phys., 1984, 81, 11, 4883., . [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]

Holmes and Lossing, 1982
Holmes, J.L.; Lossing, F.P., Heats of formation of the ionic and neutral enols of acetaldehyde and acetone, J. Am. Chem. Soc., 1982, 104, 2648. [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]

Nimlos, Soderquist, et al., 1989
Nimlos, M.R.; Soderquist, J.A.; Ellison, G.B., Spectroscopy of CH3CO- and CH3CO, J. Am. Chem. Soc., 1989, 111, 20, 7675, . [all data]

DePuy, Bierbaum, et al., 1985
DePuy, C.H.; Bierbaum, V.M.; Damrauer, R.; Soderquist, J.A., Gas-phase reactions of the acetyl anion, J. Am. Chem. Soc., 1985, 107, 3385. [all data]

Graul and Squires, 1990
Graul, S.T.; Squires, R.R., Gas-Phase Acidities Derived from Threshold Energies for Activated Reactions, J. Am. Chem. Soc., 1990, 112, 7, 2517, . [all data]

Graul and Squires, 1988
Graul, S.T.; Squires, R.R., On the Existence of Alkyl Carbanions in the Gas Phase, J. Am. Chem. Soc., 1988, 110, 2, 607, . [all data]


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