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Propanoic acid, 2-methyl-

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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:
L - 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
LL - Sharon G. Lias and Joel F. Liebman

View reactions leading to C4H8O2+ (ion structure unspecified)

Quantity Value Units Method Reference Comment
IE (evaluated)10.24 ± 0.12eVN/AN/AL

Ionization energy determinations

IE (eV) Method Reference Comment
10.12EIHolmes and Lossing, 1980LLK
10.329 ± 0.005PIWatanabe, Yokoyama, et al., 1974LLK
10.33PEWatanabe, Yokoyama, et al., 1973LLK
10.33 ± 0.03PEThomas, 1972LLK
10.02 ± 0.05PIWatanabe, Nakayama, et al., 1962RDSH
10.30PESustmann and Trill, 1972Vertical value; LLK

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
CHO2+11.28C3H7EIHolmes, Lossing, et al., 1991LL

De-protonation reactions

iPrCO2 anion + Hydrogen cation = Propanoic acid, 2-methyl-

By formula: C4H7O2- + H+ = C4H8O2

Quantity Value Units Method Reference Comment
Deltar1448. ± 8.8kJ/molG+TSCaldwell, Renneboog, et al., 1989gas phase; B
Quantity Value Units Method Reference Comment
Deltar1418. ± 8.4kJ/molIMRECaldwell, Renneboog, et al., 1989gas phase; B

References

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.

Holmes and Lossing, 1980
Holmes, J.L.; Lossing, F.P., Gas-phase heats of formation of keto and enol ions of carbonyl compounds., J. Am. Chem. Soc., 1980, 102, 1591. [all data]

Watanabe, Yokoyama, et al., 1974
Watanabe, I.; Yokoyama, Y.; Ikeda, S., Vibrational structures in the He(I) photoelectron spectra of carboxylic acids, Bull. Chem. Soc. Jpn., 1974, 47, 627. [all data]

Watanabe, Yokoyama, et al., 1973
Watanabe, I.; Yokoyama, Y.; Ikeda, S., Lone pair ionization potentials of carboxylic acids determined by He(I) photoelectron spectroscopy, Bull. Chem. Soc. Jpn., 1973, 46, 1959. [all data]

Thomas, 1972
Thomas, R.K., Photoelectron spectroscopy of hydrogen-bonded systems: spectra of monomers, dimers and mixed complexes of carboxylic acides, Proc. R. Soc. London A:, 1972, 331, 249. [all data]

Watanabe, Nakayama, et al., 1962
Watanabe, K.; Nakayama, T.; Mottl, J., Ionization potentials of some molecules, J. Quant. Spectry. Radiative Transfer, 1962, 2, 369. [all data]

Sustmann and Trill, 1972
Sustmann, R.; Trill, H., Photoelektronenspektroskopische Bestimmung von Substituenten-Effekten. II. «alpha»,«beta»-ungesattigte Carbonester, Tetrahedron Lett., 1972, 42, 4271. [all data]

Holmes, Lossing, et al., 1991
Holmes, J.L.; Lossing, F.P.; Mayer, P.M., Heats of formation of oxygen-containing organic free radicals from appearance energy measurements, J. Am. Chem. Soc., 1991, 113, 9723. [all data]

Caldwell, Renneboog, et al., 1989
Caldwell, G.; Renneboog, R.; Kebarle, P., Gas Phase Acidities of Aliphatic Carboxylic Acids, Based on Measurements of Proton Transfer Equilibria, Can. J. Chem., 1989, 67, 4, 661, https://doi.org/10.1139/v89-092 . [all data]


Notes

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