1H-1,2,4-Triazole
- Formula: C2H3N3
- Molecular weight: 69.0653
- IUPAC Standard InChIKey: NSPMIYGKQJPBQR-UHFFFAOYSA-N
- CAS Registry Number: 288-88-0
- 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. - Species with the same structure:
- Other names: s-Triazole; 1,2,4-Triazole; 1,2,4-1H-Triazole; CGA-71019; Pyrrodiazole
- Information on this page:
- Other data available:
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Phase change data
Go To: Top, Gas phase ion energetics data, Gas Chromatography, 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
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
AC - William E. Acree, Jr., James S. Chickos
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DRB - Donald R. Burgess, Jr.
DH - Eugene S. Domalski and Elizabeth D. Hearing
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
Tboil | 533.2 | K | N/A | Aldrich Chemical Company Inc., 1990 | BS |
Tboil | 477.15 | K | N/A | Bruhl, 1895 | Uncertainty assigned by TRC = 1.5 K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Tfus | 393.5 | K | N/A | Hilgeman, Mouroux, et al., 1989 | Uncertainty assigned by TRC = 0.4 K; TRC |
Tfus | 392. | K | N/A | Vorontsova and Vlasov, 1987 | Crystal phase 1 phase; Uncertainty assigned by TRC = 0.5 K; TRC |
Tfus | 295.15 | K | N/A | Bruhl, 1895 | Uncertainty assigned by TRC = 1.5 K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
ΔsubH° | 83. ± 3. | kJ/mol | AVG | N/A | Average of 6 values; Individual data points |
Enthalpy of fusion
ΔfusH (kJ/mol) | Temperature (K) | Reference | Comment |
---|---|---|---|
16.100 | 393.5 | Hilgeman, Mouroux, et al., 1989, 2 | DH |
10.76 ± 0.08 | 393.3 | Sabbah and Perez, 1999 | AC |
16.1 | 393.5 | Domalski and Hearing, 1996 | AC |
Gas phase ion energetics data
Go To: Top, Phase change data, Gas Chromatography, References, Notes
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:
B - John E. Bartmess
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
Proton affinity (review) | 886.0 | kJ/mol | N/A | Hunter and Lias, 1998 | HL |
Quantity | Value | Units | Method | Reference | Comment |
Gas basicity | 855.9 | kJ/mol | N/A | Hunter and Lias, 1998 | HL |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
9.8 | PE | Palmer, Simpson, et al., 1981 | LLK |
10.1 | PE | Palmer, Simpson, et al., 1981 | Vertical value; LLK |
10.6 | PE | Guimon, Pfister-Guillouzo, et al., 1980 | Vertical value; LLK |
10.0 | PE | Cradock, Findlay, et al., 1973 | Vertical value; LLK |
De-protonation reactions
C2H2N3- + =
By formula: C2H2N3- + H+ = C2H3N3
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 1440. ± 8.8 | kJ/mol | G+TS | Taft, 1991 | gas phase; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 1410. ± 8.4 | kJ/mol | IMRE | Taft, 1991 | gas phase; B |
Gas Chromatography
Go To: Top, Phase change data, Gas phase ion energetics 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: NIST Mass Spectrometry Data Center, William E. Wallace, director
Kovats' RI, non-polar column, isothermal
Column type | Active phase | Temperature (C) | I | Reference | Comment |
---|---|---|---|---|---|
Capillary | OV-101 | 110. | 1116. | Zhuravleva, 2000 | 50. m/0.3 mm/0.4 μm, He |
Capillary | OV-101 | 110. | 1116. | Golovnya, Kuz'menko, et al., 1999 | 50. m/0.3 mm/0.4 μm, He |
References
Go To: Top, Phase change data, Gas phase ion energetics data, Gas Chromatography, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Aldrich Chemical Company Inc., 1990
Aldrich Chemical Company Inc.,
Catalog Handbook of Fine Chemicals, Aldrich Chemical Company, Inc., Milwaukee WI, 1990, 1. [all data]
Bruhl, 1895
Bruhl, J.W.,
Spectrochemistry of Nitrogen-Containing Compounds. I.,
Z. Phys. Chem., Stoechiom. Verwandtschaftsl., 1895, 16, 193. [all data]
Hilgeman, Mouroux, et al., 1989
Hilgeman, F.R.; Mouroux, F.Y.N.; Mok, D.; Holan, M.K.,
Phase Diagrams of Binary Solid Azole Systems,
J. Chem. Eng. Data, 1989, 34, 220. [all data]
Vorontsova and Vlasov, 1987
Vorontsova, N.A.; Vlasov, O.N.,
Determination of saturated vapor pressure of Bayletone and its semiproducts,
Deposited Doc. ONIITEkhim Cherkassy, 1987, Doc. No. 1423 khp - 87, 1987. [all data]
Hilgeman, Mouroux, et al., 1989, 2
Hilgeman, F.R.; Mouroux, F.Y.N.; Mok, D.; Holan, M.K.,
Phase diagrams of binary solid azole systems,
J. Chem. Eng. Data, 1989, 34, 220-222. [all data]
Sabbah and Perez, 1999
Sabbah, Raphaël; Perez, Laurence,
Energetics of Intramolecular Bonds in 1H-1,2,4-Triazole and 1H-Benzotriazole,
Aust. J. Chem., 1999, 52, 4, 235-621, https://doi.org/10.1071/C99006
. [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]
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]
Palmer, Simpson, et al., 1981
Palmer, M.H.; Simpson, I.; Wheeler, J.R.,
Gas phase tautomerism in the triazoles and tetrazoles: A study by photoelectron spectroscopy and ab initio molecular orbital calculations,
Z. Naturforsch. A:, 1981, 36, 1246. [all data]
Guimon, Pfister-Guillouzo, et al., 1980
Guimon, C.; Pfister-Guillouzo, G.; Bernardini, A.; Viallefont, P.,
A photoelectron study (HeI, HeII) of the tautomeric equilibrium of chloro- and bromo-1,2,4-triazoles,
Tetrahedron, 1980, 36, 1071. [all data]
Cradock, Findlay, et al., 1973
Cradock, S.; Findlay, R.H.; Palmer, M.H.,
The molecular energy levels of the azoles: A study by photoelectron spectroscopy and ab initio molecular orbital calculations,
Tetrahedron, 1973, 29, 2173. [all data]
Taft, 1991
Taft, R.W.,
, personal communication, Aug, 1991. [all data]
Zhuravleva, 2000
Zhuravleva, I.L.,
Evaluation of the polarity and boiling points of nitrogen-containing heterocyclic compounds by gas chromatography,
Russ. Chem. Bull. (Engl. Transl.), 2000, 49, 2, 325-328, https://doi.org/10.1007/BF02494682
. [all data]
Golovnya, Kuz'menko, et al., 1999
Golovnya, R.V.; Kuz'menko, T.E.; Zhuravleva, I.L.,
Gas chromatographic indicator of the ability of five- and six-membered heterocyclic nitrogen-containing compounds for self-association in pure liquids,
Russ. Chem. Bull. (Engl. Transl.), 1999, 48, 4, 726-729, https://doi.org/10.1007/BF02496256
. [all data]
Notes
Go To: Top, Phase change data, Gas phase ion energetics data, Gas Chromatography, References
- Symbols used in this document:
Tboil Boiling point Tfus Fusion (melting) point ΔfusH Enthalpy of fusion ΔrG° Free energy of reaction at standard conditions ΔrH° Enthalpy of reaction at standard conditions ΔsubH° Enthalpy of sublimation at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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