Data at NIST subscription sites:

NIST subscription sites provide data under the NIST Standard Reference Data Program, but require an annual fee to access. The purpose of the fee is to recover costs associated with the development of data collections included in such sites. Your institution may already be a subscriber. Follow the links above to find out more about the data in these sites and their terms of usage.

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

Data compiled as indicated in comments:
B - John E. Bartmess
MM - Michael M. Meot-Ner (Mautner)
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

Quantity Value Units Method Reference Comment
Proton affinity (review)886.5kJ/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Gas basicity852.2kJ/molN/AHunter and Lias, 1998HL

Proton affinity at 298K

Proton affinity (kJ/mol) Reference Comment
886.3 ± 3.1Bouchoux, Buisson, et al., 2004MM
883.1 ± 1.9Bouchoux and Salpin, 2003T = 298K; MM

Gas basicity at 298K

Gas basicity (review) (kJ/mol) Reference Comment
855.4 ± 3.6Bouchoux, Buisson, et al., 2004MM
851.1 ± 1.9Bouchoux and Salpin, 2003T = 298K; MM
856. ± 3.Wu and Lebrilla, 1995T = 300K; MM

Protonation entropy at 298K

Protonation entropy (J/mol*K) Reference Comment
2. ± 6.Bouchoux, Buisson, et al., 2004MM

Ionization energy determinations

IE (eV) Method Reference Comment
8.9PECannington and Ham, 1983LBLHLM
8.8PEDebies and Rabalais, 1974LLK
9.21 ± 0.05EIZaretskii, Sadovskaya, et al., 1971LLK
9.25 ± 0.10EISvec and Junk, 1967RDSH
9.30CTSSlifkin and Allison, 1967RDSH
10.0PECannington and Ham, 1983Vertical value; LBLHLM

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
CH4N+10.27 ± 0.05?EIZaretskii, Sadovskaya, et al., 1971LLK
CH4N+10.23 ± 0.09?EISvec and Junk, 1967RDSH
CH4N+10.1 ± 0.2?EIJunk and Svec, 1963RDSH

De-protonation reactions

C2H4NO2- + Hydrogen cation = Glycine

By formula: C2H4NO2- + H+ = C2H5NO2

Quantity Value Units Method Reference Comment
Δr1434. ± 9.2kJ/molCIDCJones, Bernier, et al., 2007gas phase; B
Δr1429. ± 8.8kJ/molG+TSCaldwell, Renneboog, et al., 1989gas phase; B
Δr1433. ± 8.8kJ/molG+TSLocke and McIver, 1983gas phase; B
Δr1410. ± 5.9kJ/molEIAEMuftakhov, Vasil'ev, et al., 1999gas phase; B
Quantity Value Units Method Reference Comment
Δr1400. ± 8.4kJ/molIMRECaldwell, Renneboog, et al., 1989gas phase; B
Δr1404. ± 8.4kJ/molIMRELocke and McIver, 1983gas 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]

Bouchoux, Buisson, et al., 2004
Bouchoux, G.; Buisson, D.A.; Colas, C.; Sablier, M., Protonation thermochemistry of alpha-amino acids bearing a basic residue, European J. Mass Spectrom., 2004, 10, 977. [all data]

Bouchoux and Salpin, 2003
Bouchoux, G.; Salpin, J.Y., Gas-phase basicity of glycine, alanine, proline, serine, lysine, histidine and some of their peptides by the thermokinetic method, European J. Mass Spectrometry, 2003, 9, 391-402. [all data]

Wu and Lebrilla, 1995
Wu, J.; Lebrilla, C.B., Intrinsic Basicity of Oligomeric Peptides that Contain Glycine, Alanine, and Valine - The Effects of the Alkyl Side Chain on Proton Transfer Reactions, J. Am. Soc. Mass Spectrom., 1995, 6, 91. [all data]

Cannington and Ham, 1983
Cannington, P.H.; Ham, N.S., He(I) and He(II) photoelectron spectra of glycine and related molecules, J. Electron Spectrosc. Relat. Phenom., 1983, 32, 139. [all data]

Debies and Rabalais, 1974
Debies, T.P.; Rabalais, J.W., Electronic structure of amino acids and ureas, J. Electron Spectrosc. Relat. Phenom., 1974, 3, 315. [all data]

Zaretskii, Sadovskaya, et al., 1971
Zaretskii, V.I.; Sadovskaya, V.L.; Wulfson, N.S.; Sizoy, V.F.; Merimson, V.G., Mass spectrometry of steroid systems-XXI. Appearance and ionization potentials for the stereoisomers of the D-homoestrane series, Org. Mass Spectrom., 1971, 5, 1179. [all data]

Svec and Junk, 1967
Svec, H.J.; Junk, G.A., Electron-impact studies of substituted alkanes, J. Am. Chem. Soc., 1967, 89, 790. [all data]

Slifkin and Allison, 1967
Slifkin, M.A.; Allison, A.C., Measurement of ionization potentials from contact charge transfer spectra, Nature, 1967, 215, 949. [all data]

Junk and Svec, 1963
Junk, G.; Svec, H., The mass spectra of the α-amino acids, J. Am. Chem. Soc., 1963, 85, 839. [all data]

Jones, Bernier, et al., 2007
Jones, C.M.; Bernier, M.; Carson, E.; Colyer, K.E.; Metz, R.; Pawlow, A.; Wischow, E.D.; Webb, I.; Andriole, E.J.; Poutsma, J.C., Gas-phase Acities of the 20 Protein Amino Acids, Int. J. Mass Spectrom., 2007, 267, 1-3, 54-62, . [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, . [all data]

Locke and McIver, 1983
Locke, M.J.; McIver, R.T., Jr., Effect of Solvation on the Acid/Base Properties of Glycine, J. Am. Chem. Soc., 1983, 105, 4226. [all data]

Muftakhov, Vasil'ev, et al., 1999
Muftakhov, M.V.; Vasil'ev, Y.V.; Mazunov, V.A., Determination of electron affinity of carbonyl radicals by means of negative ion mass spectrometry, Rapid Commun. Mass Spectrom., 1999, 13, 12, 1104-1108,<1104::AID-RCM619>3.0.CO;2-C . [all data]


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