Cytosine

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Condensed phase thermochemistry 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 compiled as indicated in comments:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DH - Eugene S. Domalski and Elizabeth D. Hearing

Quantity Value Units Method Reference Comment
Δfsolid-221.3 ± 2.3kJ/molCcbWilson, Watson, et al., 1979ALS
Δfsolid-235.43 ± 0.46kJ/molCcrSabbah, Nabavian, et al., 1977ALS
Quantity Value Units Method Reference Comment
Δcsolid-2067.3 ± 2.0kJ/molCcbWilson, Watson, et al., 1979ALS
Δcsolid-2053.18 ± 0.37kJ/molCcrSabbah, Nabavian, et al., 1977ALS

Constant pressure heat capacity of solid

Cp,solid (J/mol*K) Temperature (K) Reference Comment
132.6298.Kilday, 1978DH

Phase change 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 compiled as indicated in comments:
AC - William E. Acree, Jr., James S. Chickos
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

Quantity Value Units Method Reference Comment
Δsub155.0 ± 3.0kJ/molN/ABurkinshaw and Mortimer, 1984AC
Δsub167. ± 10.kJ/molTEFerro, Bencivenni, et al., 1980AC
Δsub176. ± 10.kJ/molCSabbah, 1980ALS
Δsub176. ± 10.kJ/molCSabbah, 1980Based on data from 450. to 470. K.; AC

Enthalpy of sublimation

ΔsubH (kJ/mol) Temperature (K) Method Reference Comment
167.7 ± 0.5365.QR,MEde Barros, Medina, et al., 2006Based on data from 320. to 410. K.; AC
151.7 ± 0.7505. to 525.GSZielenkiewicz, Wszelaka-Rylik, et al., 1998AC
147.2 ± 2.6453.MEBurkinshaw and Mortimer, 1984Based on data from 423. to 483. K.; AC

Reaction thermochemistry 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 compiled as indicated in comments:
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
RCD - Robert C. Dunbar

Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. A general reaction search form is also available. Future versions of this site may rely on reaction search pages in place of the enumerated reaction displays seen below.

Individual Reactions

C4H6N3O+ + Cytosine = (C4H6N3O+ • Cytosine)

By formula: C4H6N3O+ + C4H5N3O = (C4H6N3O+ • C4H5N3O)

Quantity Value Units Method Reference Comment
Δr160.kJ/molPHPMSMeot-Ner (Mautner), 1979gas phase; M
Quantity Value Units Method Reference Comment
Δr150.J/mol*KPHPMSMeot-Ner (Mautner), 1979gas phase; M

Sodium ion (1+) + Cytosine = (Sodium ion (1+) • Cytosine)

By formula: Na+ + C4H5N3O = (Na+ • C4H5N3O)

Quantity Value Units Method Reference Comment
Δr177.kJ/molCIDCCerda and Wesdemiotis, 1996RCD

Potassium ion (1+) + Cytosine = (Potassium ion (1+) • Cytosine)

By formula: K+ + C4H5N3O = (K+ • C4H5N3O)

Quantity Value Units Method Reference Comment
Δr110.kJ/molCIDCCerda and Wesdemiotis, 1996RCD

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:
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)949.9kJ/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Gas basicity918.kJ/molN/AHunter and Lias, 1998HL

Electron affinity determinations

EA (eV) Method Reference Comment
2.34 ± 0.10LPESLi, Bowen, et al., 2007valence state of rare tautomer(H from NH2 to C5), inferred based on calculations; B
0.2300 ± 0.0080LPESSchiedt, Weinkauf, et al., 1998amino-oxo form. Dipole bound state; B
0.0850 ± 0.0080LPESSchiedt, Weinkauf, et al., 1998amino-hydroxy form. Dipole bound state; B

Ionization energy determinations

IE (eV) Method Reference Comment
8.45PEDougherty, Younathan, et al., 1978LLK
9.0 ± 0.1EIVerkin, Sukodub, et al., 1976LLK
8.9 ± 0.2EILifschitz, Bergmann, et al., 1967RDSH
8.94 ± 0.03PEHush and Cheung, 1975Vertical value; LLK

Ion clustering 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 compiled as indicated in comments:
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
RCD - Robert C. Dunbar

Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. Searches may be limited to ion clustering reactions. A general reaction search form is also available.

Clustering reactions

C4H6N3O+ + Cytosine = (C4H6N3O+ • Cytosine)

By formula: C4H6N3O+ + C4H5N3O = (C4H6N3O+ • C4H5N3O)

Quantity Value Units Method Reference Comment
Δr160.kJ/molPHPMSMeot-Ner (Mautner), 1979gas phase; M
Quantity Value Units Method Reference Comment
Δr150.J/mol*KPHPMSMeot-Ner (Mautner), 1979gas phase; M

Potassium ion (1+) + Cytosine = (Potassium ion (1+) • Cytosine)

By formula: K+ + C4H5N3O = (K+ • C4H5N3O)

Quantity Value Units Method Reference Comment
Δr110.kJ/molCIDCCerda and Wesdemiotis, 1996RCD

Sodium ion (1+) + Cytosine = (Sodium ion (1+) • Cytosine)

By formula: Na+ + C4H5N3O = (Na+ • C4H5N3O)

Quantity Value Units Method Reference Comment
Δr177.kJ/molCIDCCerda and Wesdemiotis, 1996RCD

References

Go To: Top, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering data, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Wilson, Watson, et al., 1979
Wilson, S.R.; Watson, I.D.; Malcolm, G.N., Enthalpies of formation of solid cytosine, L-histidine, and uracil, J. Chem. Thermodyn., 1979, 11, 911-912. [all data]

Sabbah, Nabavian, et al., 1977
Sabbah, R.; Nabavian, M.; Laffitte, M., Sur l'enthalpie de formation de la cytosine a 1'etat solide., C. R. Acad. Sci. Paris, 1977, 284, 953-954. [all data]

Kilday, 1978
Kilday, M.V., Enthalpies of solution of the nucleic acid bases. 3. Cytosine in water, J. Res., 1978, NBS 83, 539-546. [all data]

Burkinshaw and Mortimer, 1984
Burkinshaw, Philip M.; Mortimer, Colin T., Enthalpies of sublimation of transition metal complexes, J. Chem. Soc., Dalton Trans., 1984, 1, 75, https://doi.org/10.1039/dt9840000075 . [all data]

Ferro, Bencivenni, et al., 1980
Ferro, D.; Bencivenni, L.; Teghil, R.; Mastromarino, R., Vapour pressures and sublimation enthalpies of thymine and cytosine, Thermochimica Acta, 1980, 42, 1, 75-83, https://doi.org/10.1016/0040-6031(80)87117-6 . [all data]

Sabbah, 1980
Sabbah, R., Thermodynamics of nitrogen compounds. V. Thermochemical study of cytosine, Thermochim. Acta, 1980, 35, 73-77. [all data]

de Barros, Medina, et al., 2006
de Barros, A.L.F.; Medina, A.; Zappa, F.; Pereira, J.M.; Bessa, E.; Martins, M.H.P.; Coelho, L.F.S.; Wolff, W.; de Castro Faria, N.V., A simple experimental arrangement for measuring the vapour pressures and sublimation enthalpies by the Knudsen effusion method: Application to DNA and RNA bases, Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2006, 560, 2, 219-223, https://doi.org/10.1016/j.nima.2006.01.026 . [all data]

Zielenkiewicz, Wszelaka-Rylik, et al., 1998
Zielenkiewicz, A.; Wszelaka-Rylik, M.; Poznanski, J.; Zielenkiewicz, W., Journal of Solution Chemistry, 1998, 27, 3, 235-243, https://doi.org/10.1023/A:1022636218154 . [all data]

Meot-Ner (Mautner), 1979
Meot-Ner (Mautner), M., Ion Thermochemistry of Low Volatility Compounds in the Gas Phase. II. Intrinsic Basicities and Hydrogen Bonded Dimers of Nitrogen Heterocyclics and Nucleic Bases, J. Am. Chem. Soc., 1979, 101, 9, 2396, https://doi.org/10.1021/ja00503a027 . [all data]

Cerda and Wesdemiotis, 1996
Cerda, B.A.; Wesdemiotis, C., PAs of Peptides, J. Am. Chem. Soc., 1996, 118, 11884. [all data]

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]

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]

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]

Dougherty, Younathan, et al., 1978
Dougherty, D.; Younathan, E.S.; Voll, R.; Abdulnur, S.; McGlynn, S.P., Photoelectron spectroscopy of some biological molecules, J. Electron Spectrosc. Relat. Phenom., 1978, 13, 379. [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]

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]

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]


Notes

Go To: Top, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering data, References