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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 CH2O+ (ion structure unspecified)

Quantity Value Units Method Reference Comment
IE (evaluated)10.88 ± 0.01eVN/AN/AL
Quantity Value Units Method Reference Comment
Proton affinity (review)712.9kJ/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Gas basicity683.3kJ/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Deltaf(+) ion941.8kJ/molN/AN/A 
Quantity Value Units Method Reference Comment
DeltafH(+) ion,0K946.0kJ/molN/AN/A 

Proton affinity at 298K

Proton affinity (kJ/mol) Reference Comment
711.5 ± 2.1Bouchoux and Leblanc, 2000T = 300K; MM

Gas basicity at 298K

Gas basicity (review) (kJ/mol) Reference Comment
681.5 ± 0.7Bouchoux and Leblanc, 2000T = 300K; MM

Ionization energy determinations

IE (eV) Method Reference Comment
10.88CIOhno, Okamura, et al., 1995LL
10.8887 ± 0.0030PENiu, Shirley, et al., 1993LL
10.86PITraeger, 1985LBLHLM
10.88PEKimura, Katsumata, et al., 1981LLK
10.9PEVon Niessen, Bieri, et al., 1980LLK
10.885 ± 0.005PEHernandez, Masclet, et al., 1977LLK
10.874 ± 0.002SDrury-Lessard and Moule, 1977LLK
10.868 ± 0.005PIGuyon, Chupka, et al., 1976LLK
10.88 ± 0.02PIWarneck, 1971LLK
10.87 ± 0.01PIMentall, Gentieu, et al., 1971LLK
10.88 ± 0.02PIMatthews and Warneck, 1969RDSH
10.884PEBaker, Baker, et al., 1968RDSH
10.86 ± 0.02EIKanomata, 1961RDSH
10.90 ± 0.03PIVilesov, 1960RDSH
10.87 ± 0.01PIWatanabe, 1957RDSH
10.88 ± 0.01SPrice, 1935RDSH
10.1PERao, 1975Vertical value; LLK

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
CHO+11.97HPITraeger, 1985LBLHLM
CHO+13.94 ± 0.40HEIWankenne, Caprace, et al., 1984LBLHLM
CHO+11.92 ± 0.01HPIGuyon, Chupka, et al., 1976LLK
CHO+11.89 ± 0.03HPIWarneck, 1971LLK
CHO+11.95 ± 0.06HPIMatthews and Warneck, 1969RDSH
CO+14.10 ± 0.08H2PIGuyon, Chupka, et al., 1976LLK
CO+18.7 ± 0.2?EIBrand and Reed, 1957RDSH
H+17.41 ± 0.07CHOPIWarneck, 1971LLK
H2+15.42 ± 0.06COPIWarneck, 1971LLK

De-protonation reactions

CHO- + Hydrogen cation = Formaldehyde

By formula: CHO- + H+ = CH2O

Quantity Value Units Method Reference Comment
Deltar1650.7 ± 0.96kJ/molD-EAMurray, Miller, et al., 1986gas phase; B
Quantity Value Units Method Reference Comment
Deltar1617.7 ± 1.7kJ/molH-TSMurray, Miller, et al., 1986gas phase; B
Deltar1648. ± 19.kJ/molIMRBKarpas and Klein, 1975gas 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]

Bouchoux and Leblanc, 2000
Bouchoux, G.; Leblanc, D., Gas-phase basicity of formaldehyde by the thermokinetic method, European J. Mass Spectrom., 2000, 6, 443. [all data]

Ohno, Okamura, et al., 1995
Ohno, K.; Okamura, K.; Yamakado, H.; Hoshino, S.; Takami, T.; Yamauchi, M., Penning ionization of HCHO, CH2CH2, and CH2CHCHO by collision with He*(2 3S) metastable atoms, J. Phys. Chem., 1995, 99, 14247. [all data]

Niu, Shirley, et al., 1993
Niu, B.; Shirley, D.A.; Bai, Y., High resolution photoelectron spectroscopy and femtosecond intramolecular dynamics of H2CO+ and D2CO+, J. Chem. Phys., 1993, 98, 4377. [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]

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]

Von Niessen, Bieri, et al., 1980
Von Niessen, W.; Bieri, G.; Asbrink, L., 30.4 nm He(II) photoelectron spectra of organic molecules. Part III. Oxo-compounds (C,H,O), J. Electron Spectrosc. Relat. Phenom., 1980, 21, 175. [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]

Drury-Lessard and Moule, 1977
Drury-Lessard, C.R.; Moule, D.C., The higher Rydberg states of formaldehyde, Chem. Phys. Lett., 1977, 47, 300. [all data]

Guyon, Chupka, et al., 1976
Guyon, P.M.; Chupka, W.A.; Berkowitz, J., Photoionization mass spectrometric study of formaldehyde H2CO, HDCO, and D2CO, J. Chem. Phys., 1976, 65, 1419. [all data]

Warneck, 1971
Warneck, P., Photoionisation von methanol und formaldehyd, Z. Naturforsch. A:, 1971, 26, 2047. [all data]

Mentall, Gentieu, et al., 1971
Mentall, J.E.; Gentieu, E.P.; Krauss, M.; Neumann, D., Photoionization and absorption spectrum of formaldehyde in the vacuum ultraviolet, J. Chem. Phys., 1971, 55, 5471. [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]

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]

Kanomata, 1961
Kanomata, I., Mass-spectrometric study on ionization and dissociation of formaldehyde, acetaldehyde, acetone and ethyl methyl ketone by electron impact, Bull. Chem. Soc. Japan, 1961, 34, 1864. [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]

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

Price, 1935
Price, W.C., The far ultraviolet absorption spectra of formaldehyde and the alkyl derivatives of H, O and H2S, J. Chem. Phys., 1935, 3, 256. [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]

Wankenne, Caprace, et al., 1984
Wankenne, H.; Caprace, G.; Momigny, J., Unimolecular decay of metastable ions in formaldehyde, Int. J. Mass Spectrom. Ion Processes, 1984, 57, 149. [all data]

Brand and Reed, 1957
Brand, J.C.D.; Reed, R.I., The electronic spectrum of formaldehyde. Part II. Mechanisms of dissociation of formaldehyde and the formaldehyde molecular ion, J. Chem. Soc., 1957, 2386. [all data]

Murray, Miller, et al., 1986
Murray, K.K.; Miller, T.M.; Leopold, D.G.; Lineberger, W.C., Laser photoelectron spectroscopy of the Formylf anion, J. Chem. Phys., 1986, 84, 2520. [all data]

Karpas and Klein, 1975
Karpas, Z.; Klein, F.S., Negative ion-molecule reactions in a mixture of ammonia-formaldehyde - an ICR mass spectrometry study, Int. J. Mass Spectrom. Ion Phys., 1975, 18, 65. [all data]


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