Cytosine

• Formula: C₄H₅N₃O
• Molecular weight: 111.1020
• IUPAC Standard InChI: InChI=1S/C4H5N3O/c5-3-1-2-6-4(8)7-3/h1-2H,(H3,5,6,7,8) Copy

  
• IUPAC Standard InChIKey: OPTASPLRGRRNAP-UHFFFAOYSA-N Copy
• CAS Registry Number: 71-30-7
• Chemical structure:
  This structure is also available as a 2d Mol file
• Other names: 2(1H)-Pyrimidinone, 4-amino-; Cyt; Cytosinimine; 4-Amino-2(1H)-pyrimidinone; 4-Amino-2-hydroxypyrimidine; 4-Amino-2(1H)pyrimidone; 4-Amino-2-oxypyrimidine
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• Information on this page:
  • Gas phase thermochemistry data
  • Phase change data
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Condensed phase thermochemistry data
  • Reaction thermochemistry data
  • Ion clustering data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
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Gas 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 by: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

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

Enthalpy of sublimation

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

Electron affinity determinations

Ionization energy determinations

References

Go To: Top, Gas phase thermochemistry data, Phase change data, 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.

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

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]

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

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• Symbols used in this document:
  

  EA	Electron affinity
  ΔfH°gas	Enthalpy of formation of gas at standard conditions
  ΔsubH	Enthalpy of sublimation
  ΔsubH°	Enthalpy of sublimation at standard conditions

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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