Cytosine
- Formula: C4H5N3O
- Molecular weight: 111.1020
- IUPAC Standard InChIKey: OPTASPLRGRRNAP-UHFFFAOYSA-N
- 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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Gas phase thermochemistry data
Go To: Top, Condensed phase thermochemistry data, Phase change data, References, Notes
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
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔfH°gas | -14.2 ± 2.4 | kcal/mol | Cm | Sabbah, 1980 |
Condensed phase thermochemistry data
Go To: Top, Gas phase thermochemistry data, Phase change data, References, Notes
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 |
---|---|---|---|---|---|
ΔfH°solid | -52.89 ± 0.55 | kcal/mol | Ccb | Wilson, Watson, et al., 1979 | ALS |
ΔfH°solid | -56.27 ± 0.11 | kcal/mol | Ccr | Sabbah, Nabavian, et al., 1977 | ALS |
Quantity | Value | Units | Method | Reference | Comment |
ΔcH°solid | -494.10 ± 0.48 | kcal/mol | Ccb | Wilson, Watson, et al., 1979 | ALS |
ΔcH°solid | -490.722 ± 0.088 | kcal/mol | Ccr | Sabbah, Nabavian, et al., 1977 | ALS |
Constant pressure heat capacity of solid
Cp,solid (cal/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
31.69 | 298. | Kilday, 1978 | DH |
Phase change data
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, References, Notes
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 |
---|---|---|---|---|---|
ΔsubH° | 37.05 ± 0.72 | kcal/mol | N/A | Burkinshaw and Mortimer, 1984 | AC |
ΔsubH° | 39.9 ± 2.4 | kcal/mol | TE | Ferro, Bencivenni, et al., 1980 | AC |
ΔsubH° | 42.1 ± 2.4 | kcal/mol | C | Sabbah, 1980 | ALS |
ΔsubH° | 42.1 ± 2.4 | kcal/mol | C | Sabbah, 1980 | Based on data from 450. to 470. K.; AC |
Enthalpy of sublimation
ΔsubH (kcal/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
40.1 ± 0.1 | 365. | QR,ME | de Barros, Medina, et al., 2006 | Based on data from 320. to 410. K.; AC |
36.3 ± 0.2 | 505. to 525. | GS | Zielenkiewicz, Wszelaka-Rylik, et al., 1998 | AC |
35.18 ± 0.62 | 453. | ME | Burkinshaw and Mortimer, 1984 | Based on data from 423. to 483. K.; AC |
References
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change 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]
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]
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]
Notes
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, References
- Symbols used in this document:
Cp,solid Constant pressure heat capacity of solid ΔcH°solid Enthalpy of combustion of solid at standard conditions ΔfH°gas Enthalpy of formation of gas at standard conditions ΔfH°solid Enthalpy of formation of solid 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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