1,3-Diazine
- Formula: C4H4N2
- Molecular weight: 80.0880
- IUPAC Standard InChI: InChI=1S/C4H4N2/c1-2-5-4-6-3-1/h1-4H
- IUPAC Standard InChIKey: CZPWVGJYEJSRLH-UHFFFAOYSA-N
- CAS Registry Number: 289-95-2
- Chemical structure:
This structure is also available as a 2d Mol file or as a computed 3d SD file
The 3d structure may be viewed using Java or Javascript. - Other names: Pyrimidine; m-Diazine; Metadiazine; Miazine; 1,3-Diazabenzene; Py; Pyr
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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 | 195.8 ± 1.5 | kJ/mol | Ccr | Nabavian, Sabbah, et al., 1977 | Reanalyzed by Pedley, Naylor, et al., 1986, Original value = 193.1 ± 2.0 kJ/mol |
| ΔfH°gas | 195.9 ± 1.4 | kJ/mol | Ccb | Tjebbes, 1962 | Reanalyzed by Cox and Pilcher, 1970, Original value = 196.6 ± 1.0 kJ/mol |
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 by: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔfH°liquid | 143.2 ± 1.8 | kJ/mol | Ccr | Nabavian, Sabbah, et al., 1977 | |
| ΔfH°liquid | 146.6 ± 0.84 | kJ/mol | Ccb | Tjebbes, 1962 | |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔcH°liquid | -2288.9 ± 1.8 | kJ/mol | Ccr | Nabavian, Sabbah, et al., 1977 | |
| ΔcH°liquid | -2292.3 ± 0.84 | kJ/mol | Ccb | Tjebbes, 1962 |
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:
BS - Robert L. Brown and Stephen E. Stein
AC - William E. Acree, Jr., James S. Chickos
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DRB - Donald R. Burgess, Jr.
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| Tboil | 396.7 | K | N/A | Weast and Grasselli, 1989 | BS |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔvapH° | 49. ± 7. | kJ/mol | AVG | N/A | Average of 7 values; Individual data points |
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.
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]
Pedley, Naylor, et al., 1986
Pedley, J.B.; Naylor, R.D.; Kirby, S.P.,
Thermochemical Data of Organic Compounds, Chapman and Hall, New York, 1986, 1-792. [all data]
Tjebbes, 1962
Tjebbes, J.,
The heats of combustion and formation of the three diazines and their resonance energies,
Acta Chem. Scand., 1962, 16, 916-921. [all data]
Cox and Pilcher, 1970
Cox, J.D.; Pilcher, G.,
Thermochemistry of Organic and Organometallic Compounds, Academic Press, New York, 1970, 1-636. [all data]
Weast and Grasselli, 1989
CRC Handbook of Data on Organic Compounds, 2nd Editon, Weast,R.C and Grasselli, J.G., ed(s)., CRC Press, Inc., Boca Raton, FL, 1989, 1. [all data]
Notes
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, References
- Symbols used in this document:
Tboil Boiling point ΔcH°liquid Enthalpy of combustion of liquid at standard conditions ΔfH°gas Enthalpy of formation of gas at standard conditions ΔfH°liquid Enthalpy of formation of liquid at standard conditions ΔvapH° Enthalpy of vaporization at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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