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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

Data compiled as indicated in comments:
MM - Michael M. Meot-Ner (Mautner)
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron
B - John E. Bartmess

Quantity Value Units Method Reference Comment
Proton affinity (review)872.7kJ/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Gas basicity841.7kJ/molN/AHunter and Lias, 1998HL

Electron affinity determinations

EA (eV) Method Reference Comment
0.07502N/ADesfrancois, Abdoul-Carime, et al., 1999B
0.0860 ± 0.0080LPESSchiedt, Weinkauf, et al., 1998B
0.054 ± 0.035N/ADesfrancois, Abdoul-Carime, et al., 1996B
0.0930 ± 0.0070LPESHendricks, Lyapustina, et al., 1996 Aflatooni, Gallup, et al., 1998: vertical attachment EA = -0.22 eV; B
2.49 ± 0.10LPESLi, Bowen, et al., 2007valence state of rare tautomer(N3-H to C5) inferred from calculations; B

Proton affinity at 298K

Proton affinity (kJ/mol) Reference Comment
858.Wolken and Turecek, 2000PA calculated by B3YLP, MP2, QCSID, QCISD(T)6-31G(d,p) to 6-311+G(3df,2p) methods. The results, and comparison with experimental PA of thymine suggest the cited value, probbaly more accurate than 1975 Wilson and McCoskey bracketing value.; MM

Ionization energy determinations

IE (eV) Method Reference Comment
9.2PEYu, O'Donnell, et al., 1981LLK
9.4 ± 0.1EIVerkin, Sukodub, et al., 1976LLK
9.53 ± 0.02EIZaretskii, Sadovskaya, et al., 1971LLK
9.8 ± 0.1EILifschitz, Bergmann, et al., 1967RDSH
9.68PEPalmer, Simpson, et al., 1980Vertical value; LLK
9.60PEDougherty, Wittel, et al., 1976Vertical value; LLK
9.45PELauer, Schafer, et al., 1975Vertical value; LLK
9.50 ± 0.03PEHush and Cheung, 1975Vertical value; LLK
9.59PEPadva, LeBreton, et al., 1974Vertical value; LLK


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]

Desfrancois, Abdoul-Carime, et al., 1999
Desfrancois, C.; Abdoul-Carime, H.; Carles, S.; Periquet, V.; Schermann, J.P.; Smith, D.M.A.; Adamowicz, L., Experimental and theoretical ab initio study of the influence of N-methylation on the dipole-bound electron affinities of thymine and uracil, J. Chem. Phys., 1999, 110, 24, 11876-11883, https://doi.org/10.1063/1.479175 . [all data]

Schiedt, Weinkauf, et al., 1998
Schiedt, J.; Weinkauf, R.; Neumark, D.M.; Schlag, E.W., Anion spectroscopy of uracil, thymine and the amino-oxo and amino-hydroxy tautomers of cytosine and their water clusters, Chem. Phys., 1998, 239, 1-3, 511-524, https://doi.org/10.1016/S0301-0104(98)00361-9 . [all data]

Desfrancois, Abdoul-Carime, et al., 1996
Desfrancois, C.; Abdoul-Carime, H.; Schermann, J.P., Electron Attachment to Isolated Nucleic Acid Bases, J. Chem. Phys., 1996, 104, 19, 7792, https://doi.org/10.1063/1.471484 . [all data]

Hendricks, Lyapustina, et al., 1996
Hendricks, J.H.; Lyapustina, S.A.; de Clercq, H.L.; Snodgrass, J.T.; Bowen, K.H., Dipole bound, nucleic Acid Base Anions Studied via Negative Ion Photoelectron Spectroscopy, J. Chem. Phys., 1996, 104, 19, 7788, https://doi.org/10.1063/1.471482 . [all data]

Aflatooni, Gallup, et al., 1998
Aflatooni, K.; Gallup, G.A.; Burrows, P.D., Electron Attachment Energies of the DNA Bases, J. Phys. Chem., 1998, 102, 31, 6205, https://doi.org/10.1021/jp980865n . [all data]

Li, Bowen, et al., 2007
Li, X.; Bowen, K.H.; Haranczyk, M.; Bachorz, R.A.; Mazurkiewicz, K.; Rak, J.; Gutowski, M., Photoelectron spectroscopy of adiabatically bound valence anions of rare tautomers of the nucleic acid bases, J. Chem. Phys., 2007, 127, 17, 174309, https://doi.org/10.1063/1.2795719 . [all data]

Wolken and Turecek, 2000
Wolken, J.K.; Turecek, F., Proton affinity of uracil. A computational study of protonation sites, J. Am. Soc. Mass Spectrom., 2000, 11, 1065. [all data]

Yu, O'Donnell, et al., 1981
Yu, C.; O'Donnell, T.J.; LeBreton, P.R., Ultraviolet photoelectron studies of volatile nucleoside models. Vertical ionization potential measurements of methylated uridine, thymidine, cytidine, and adenosine, J. Phys. Chem., 1981, 85, 3851. [all data]

Verkin, Sukodub, et al., 1976
Verkin, B.I.; Sukodub, L.F.; Yanson, I.K., Ionization potentials of nitrogenous bases of of nucleic acids, Dokl. Akad. Nauk SSSR, 1976, 228, 1452. [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]

Lifschitz, Bergmann, et al., 1967
Lifschitz, C.; Bergmann, E.D.; Pullman, B., The ionization potentials of biological purines and pyrimidines, Tetrahedron Lett., 1967, 4583. [all data]

Palmer, Simpson, et al., 1980
Palmer, M.H.; Simpson, I.; Platenkamp, R.J., The electronic structure of flavin derivatives, J. Mol. Struct., 1980, 66, 243. [all data]

Dougherty, Wittel, et al., 1976
Dougherty, D.; Wittel, K.; Meeks, J.; McGlynn, S.P., Photoelectron spectroscopy of carbonyls. Ureas, uracils, and thymine, J. Am. Chem. Soc., 1976, 98, 3815. [all data]

Lauer, Schafer, et al., 1975
Lauer, G.; Schafer, W.; Schweig, A., Functional subunits in the nucleic acid bases uracil and thymine, Tetrahedron Lett., 1975, 45, 3939. [all data]

Hush and Cheung, 1975
Hush, N.S.; Cheung, A.S., Ionization potentials and donor properties of nucleic acid bases and related compounds, Chem. Phys. Lett., 1975, 34, 11. [all data]

Padva, LeBreton, et al., 1974
Padva, A.; LeBreton, P.R.; Dinerstein, R.J.; Ridyard, J.N.A., UV photoelectron studies of biological pyrimidines: The electronic structure of uracil, Biochem. Biophys. Res. Commun., 1974, 60, 1262. [all data]


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