Thymine
- Formula: C5H6N2O2
- Molecular weight: 126.1133
- IUPAC Standard InChIKey: RWQNBRDOKXIBIV-UHFFFAOYSA-N
- CAS Registry Number: 65-71-4
- Chemical structure:
This structure is also available as a 2d Mol file - Other names: 2,4(1H,3H)-Pyrimidinedione, 5-methyl-; Thymin; 2,4-Dihydroxy-5-methylpyrimidine; 5-Methyluracil; 5-Methyl-2,4-dioxypyrimidine; 5-Methyl-2,4(1H,3H)-pyrimidinedione
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Gas phase thermochemistry data
Go To: Top, Condensed phase thermochemistry data, Phase change data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), UV/Visible spectrum, 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 | -328.7 ± 4.3 | kJ/mol | Ccr | Nabavian, Sabbah, et al., 1977 |
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 |
---|---|---|---|---|---|
ΔfH°liquid | -462.80 ± 0.84 | kJ/mol | Ccr | Nabavian, Sabbah, et al., 1977 | ALS |
Quantity | Value | Units | Method | Reference | Comment |
ΔcH°liquid | -2362.23 ± 0.84 | kJ/mol | Ccr | Nabavian, Sabbah, et al., 1977 | ALS |
Quantity | Value | Units | Method | Reference | Comment |
ΔcH°solid | -2369. | kJ/mol | Ccb | Fischer and Wrede, 1904 | Heat of combustion corrected for pressure; ALS |
ΔcH°solid | -2367.3 | kJ/mol | Ccb | Lemoult, 1904 | ALS |
Constant pressure heat capacity of solid
Cp,solid (J/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
150.2 | 298. | Kilday, 1978 | DH |
151.4 | 298.15 | Alvarez and Biltonen, 1973 | DH |
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:
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
AC - William E. Acree, Jr., James S. Chickos
DH - Eugene S. Domalski and Elizabeth D. Hearing
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
Tfus | 321.3 | K | N/A | Eykman, 1889 | Uncertainty assigned by TRC = 1. K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
ΔvapH° | 134.1 ± 4.2 | kJ/mol | V | Nabavian, Sabbah, et al., 1977 | ALS |
Quantity | Value | Units | Method | Reference | Comment |
ΔsubH° | 131.3 ± 4.0 | kJ/mol | N/A | Burkinshaw and Mortimer, 1984 | AC |
ΔsubH° | 138. ± 10. | kJ/mol | TE | Ferro, Bencivenni, et al., 1980 | AC |
ΔsubH° | 134.1 ± 4.2 | kJ/mol | C | Nabavian, Sabbah, et al., 1977, 2 | AC |
Enthalpy of sublimation
ΔsubH (kJ/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
125.7 ± 3.6 | 411. | ME | Burkinshaw and Mortimer, 1984 | Based on data from 383. to 438. K.; AC |
124.4 ± 1.3 | 403. | QR | Teplitsky, Yanson, et al., 1980 | Based on data from 378. to 428. K.; AC |
Enthalpy of fusion
ΔfusH (kJ/mol) | Temperature (K) | Reference | Comment |
---|---|---|---|
17.51 | 321.3 | Domalski and Hearing, 1996 | AC |
17.510 | 321.3 | Eykman, 1889, 2 | DH |
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) | 880.9 | kJ/mol | N/A | Hunter and Lias, 1998 | HL |
Quantity | Value | Units | Method | Reference | Comment |
Gas basicity | 850.0 | kJ/mol | N/A | Hunter and Lias, 1998 | HL |
Electron affinity determinations
EA (eV) | Method | Reference | Comment |
---|---|---|---|
0.0690 ± 0.0070 | LPES | Hendricks, Lyapustina, et al., 1996 | Aflatooni, Gallup, et al., 1998: vertical attachment EA = -0.29 eV; B |
2.40 ± 0.10 | LPES | Li, Bowen, et al., 2007 | valence state of rare tautomer(N3-H to C5) inferred from calculations; B |
0.06999 | N/A | Desfrancois, Abdoul-Carime, et al., 1999 | B |
0.0620 ± 0.0080 | LPES | Schiedt, Weinkauf, et al., 1998 | B |
0.068 ± 0.020 | N/A | Desfrancois, Abdoul-Carime, et al., 1996 | B |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
9.0 ± 0.1 | EI | Verkin, Sukodub, et al., 1976 | LLK |
9.4 ± 0.1 | EI | Lifschitz, Bergmann, et al., 1967 | RDSH |
9.20 | PE | Dougherty, Wittel, et al., 1976 | Vertical value; LLK |
9.02 | PE | Lauer, Schafer, et al., 1975 | Vertical value; LLK |
9.14 ± 0.03 | PE | Hush and Cheung, 1975 | Vertical value; LLK |
IR Spectrum
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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: Coblentz Society, Inc.
Condensed Phase Spectrum
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Notice: Except where noted, spectra from this collection were measured on dispersive instruments, often in carefully selected solvents, and hence may differ in detail from measurements on FTIR instruments or in other chemical environments. More information on the manner in which spectra in this collection were collected can be found here.
Notice: Concentration information is not available for this spectrum and, therefore, molar absorptivity values cannot be derived.
Additional Data
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Owner | Copyright (C) 1987 by the Coblentz Society Collection (C) 2018 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved. |
---|---|
Origin | K. K. DEB-NCI FREDERICK CANCER RESEARCH CENTER |
Source reference | COBLENTZ NO. 9740 |
Date | 1974/08/20 |
Name(s) | 5-methyl-2,4(1H,3H)-pyrimidinedione 5-methyluracil |
State | SOLID (1.8 mg / 500 mg KBr DISC) |
Instrument | PERKIN-ELMER 180 (GRATING) |
Instrument parameters | GRATINGS: 2000, 1000, 500, 250 CM-1; FILTER CHANGE: 2970, 2000, 1485, 1000, 743, 500, 372, 250, 186 CM-1. |
Resolution | 2 |
Sampling procedure | TRANSMISSION |
Data processing | DIGITIZED BY COBLENTZ SOCIETY (BATCH II) FROM HARD COPY |
Mass spectrum (electron ionization)
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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: NIST Mass Spectrometry Data Center, William E. Wallace, director
Spectrum
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Additional Data
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Owner | NIST Mass Spectrometry Data Center Collection (C) 2014 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved. |
---|---|
Origin | Japan AIST/NIMC Database- Spectrum MS-NW- 639 |
NIST MS number | 228115 |
UV/Visible spectrum
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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Spectrum
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Additional Data
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Source | Wilson, 1948 |
---|---|
Owner | INEP CP RAS, NIST OSRD Collection (C) 2007 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved. |
Origin | INSTITUTE OF ENERGY PROBLEMS OF CHEMICAL PHYSICS, RAS |
Source reference | RAS UV No. 11048 |
Instrument | n.i.g. |
Melting point | 316 |
References
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), UV/Visible spectrum, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Nabavian, Sabbah, et al., 1977
Nabavian, P.M.; Sabbah, R.; Chastel, R.; Laffitte, M.,
Thermodynamique de composes azotes. II. Etude thermochimique des acides aminobenzoiques, de la pyrimidine, de l'uracile et de la thymine.,
J. Chim. Phys., 1977, 74, 115-126. [all data]
Fischer and Wrede, 1904
Fischer, E.; Wrede, F.,
Uber die Verbrennungswarme einiger organischer Verbindungen,
Sitzungsber. Dtsch. Akad. Wiss. Berlin Kl. Math. Phys. Tech., 1904, 687-715. [all data]
Lemoult, 1904
Lemoult, M.P.,
Remarques sur une serie recenie de determinations calorimetriques,
Compt. Rend., 1904, 663-635. [all data]
Kilday, 1978
Kilday, M.V.,
Enthalpies of solution of the nucleic acid bases. 2. Thymine in water,
J. Res., 1978, NBS 83, 529-537. [all data]
Alvarez and Biltonen, 1973
Alvarez, J.; Biltonen, R.,
Nucleic acid-solvent interactions: temperature dependence of the heat of solution of thymine in water and ethanol,
Biopolymers, 1973, 12, 1815-1828. [all data]
Eykman, 1889
Eykman, J.F.,
Z. Phys. Chem., Stoechiom. Verwandtschaftsl., 1889, 4, 497. [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]
Nabavian, Sabbah, et al., 1977, 2
Nabavian, M.; Sabbah, R.; Chastel, R.; Laffitte, M.,
J. Chim. Phys.Phys.-Chim. Biol., 1977, 74, 115. [all data]
Teplitsky, Yanson, et al., 1980
Teplitsky, A.B.; Yanson, I.K.; Glukhova, O.T.; Zielenkiwicz, A.; Zielenkiewicz, W.; Wierzchowski, K.L.,
Thermochemistry of aqueous solutions of alkylated nucleic acid bases,
Biophysical Chemistry, 1980, 11, 1, 17-21, https://doi.org/10.1016/0301-4622(80)85003-4
. [all data]
Domalski and Hearing, 1996
Domalski, Eugene S.; Hearing, Elizabeth D.,
Heat Capacities and Entropies of Organic Compounds in the Condensed Phase. Volume III,
J. Phys. Chem. Ref. Data, 1996, 25, 1, 1, https://doi.org/10.1063/1.555985
. [all data]
Eykman, 1889, 2
Eykman, J.F.,
Zur kryoskopischen Molekulargewichtsbestimmung,
Z. Physik. Chem., 1889, 4, 497-519. [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]
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]
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]
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]
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]
Wilson, 1948
Wilson, W.,
J. Chem. Soc., 1948, 1157. [all data]
Notes
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), UV/Visible spectrum, References
- Symbols used in this document:
Cp,solid Constant pressure heat capacity of solid EA Electron affinity Tfus Fusion (melting) point ΔcH°liquid Enthalpy of combustion of liquid at standard conditions ΔcH°solid Enthalpy of combustion of solid at standard conditions ΔfH°gas Enthalpy of formation of gas at standard conditions ΔfH°liquid Enthalpy of formation of liquid at standard conditions ΔfusH Enthalpy of fusion ΔsubH Enthalpy of sublimation ΔsubH° Enthalpy of sublimation at standard conditions ΔvapH° Enthalpy of vaporization at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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