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1H-1,2,4-Triazole

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Gas phase thermochemistry data

Go To: Top, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering data, Mass spectrum (electron ionization), 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
DRB - Donald R. Burgess, Jr.

Quantity Value Units Method Reference Comment
Deltafgas192.7 ± 0.8kJ/molCcbJimenez, Roux, et al., 1989ALS
Deltafgas193.7 ± 1.9kJ/molCcbFaour and Akasheh, 1985ALS
Deltafgas188.5kJ/molN/AMasalitinova, Oleinikova, et al., 1984Value computed using «DELTA»fHsolid° value of 107.9±0.5 kj/mol from Masalitinova, Oleinikova, et al., 1984 and «DELTA»subH° value of 80.6 kj/mol from Jimenez, Roux, et al., 1989.; DRB
Deltafgas189.8kJ/molN/AAleksandrov, Osipova, et al., 1982Value computed using «DELTA»fHsolid° value of 109.2±0.9 kj/mol from Aleksandrov, Osipova, et al., 1982 and «DELTA»subH° value of 80.6 kj/mol from Jimenez, Roux, et al., 1989.; DRB

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
Deltafsolid108.7 ± 0.4kJ/molCcbJimenez, Roux, et al., 1989ALS
Deltafsolid113.1 ± 1.4kJ/molCcbFaour and Akasheh, 1985ALS
Deltafsolid107.89 ± 0.46kJ/molCcbMasalitinova, Oleinikova, et al., 1984ALS
Deltafsolid109.22 ± 0.94kJ/molCcbAleksandrov, Osipova, et al., 1982ALS
Quantity Value Units Method Reference Comment
Deltacsolid-1324.4 ± 0.3kJ/molCcbJimenez, Roux, et al., 1989ALS
Deltacsolid-1328.9 ± 1.2kJ/molCcbFaour and Akasheh, 1985ALS
Deltacsolid-1323.66 ± 0.37kJ/molCcbMasalitinova, Oleinikova, et al., 1984ALS
Deltacsolid-1324.99 ± 0.90kJ/molCcbAleksandrov, Osipova, et al., 1982ALS
Deltacsolid-1325.kJ/molCcbZimmerman and Geisenfelder, 1961ALS

Constant pressure heat capacity of solid

Cp,solid (J/mol*K) Temperature (K) Reference Comment
78.7298.15Jimenez, Roux, et al., 1989DH

Phase change data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering data, Mass spectrum (electron ionization), 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
Tboil533.2KN/AAldrich Chemical Company Inc., 1990BS
Tboil477.15KN/ABruhl, 1895Uncertainty assigned by TRC = 1.5 K; TRC
Quantity Value Units Method Reference Comment
Tfus393.5KN/AHilgeman, Mouroux, et al., 1989Uncertainty assigned by TRC = 0.4 K; TRC
Tfus392.KN/AVorontsova and Vlasov, 1987Crystal phase 1 phase; Uncertainty assigned by TRC = 0.5 K; TRC
Tfus295.15KN/ABruhl, 1895Uncertainty assigned by TRC = 1.5 K; TRC
Quantity Value Units Method Reference Comment
Deltasub83. ± 3.kJ/molAVGN/AAverage of 6 values; Individual data points

Enthalpy of fusion

DeltafusH (kJ/mol) Temperature (K) Reference Comment
16.100393.5Hilgeman, Mouroux, et al., 1989, 2DH
10.76 ± 0.08393.3Sabbah and Perez, 1999AC
16.1393.5Domalski and Hearing, 1996AC

In addition to the Thermodynamics Research Center (TRC) data available from this site, much more physical and chemical property data is available from the following TRC products:


Reaction thermochemistry data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Gas phase ion energetics data, Ion clustering data, Mass spectrum (electron ionization), 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:
B - John E. Bartmess
RCD - Robert C. Dunbar
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. A general reaction search form is also available. Future versions of this site may rely on reaction search pages in place of the enumerated reaction displays seen below.

Individual Reactions

C2H2N3- + Hydrogen cation = 1H-1,2,4-Triazole

By formula: C2H2N3- + H+ = C2H3N3

Quantity Value Units Method Reference Comment
Deltar1440. ± 8.8kJ/molG+TSTaft, 1991gas phase; B
Quantity Value Units Method Reference Comment
Deltar1410. ± 8.4kJ/molIMRETaft, 1991gas phase; B

Sodium ion (1+) + 1H-1,2,4-Triazole = (Sodium ion (1+) bullet 1H-1,2,4-Triazole)

By formula: Na+ + C2H3N3 = (Na+ bullet C2H3N3)

Quantity Value Units Method Reference Comment
Deltar124. ± 5.0kJ/molCIDTRodgers and Armentrout, 2000RCD

Free energy of reaction

DeltarG° (kJ/mol) T (K) Method Reference Comment
0.00.CIDTRodgers and Armentrout, 2000RCD

1-[1,2,4]Triazol-1-ylethanone + Water = 1H-1,2,4-Triazole + Acetic acid

By formula: C4H5N3O + H2O = C2H3N3 + C2H4O2

Quantity Value Units Method Reference Comment
Deltar-30.5 ± 0.3kJ/molCmWadso, 1960solid phase; Heat of hydrolysis; ALS

1-Butanamine + 1-[1,2,4]Triazol-1-ylethanone = Acetamide, N-butyl- + 1H-1,2,4-Triazole

By formula: C4H11N + C4H5N3O = C6H13NO + C2H3N3

Quantity Value Units Method Reference Comment
Deltar-85.8 ± 0.3kJ/molCmWadso, 1962solid phase; ALS

1H-1,2,3-Triazole = 1H-1,2,4-Triazole

By formula: C2H3N3 = C2H3N3

Quantity Value Units Method Reference Comment
Deltar12.kJ/molEqkMauret, Fayet, et al., 1973liquid phase; solvent: Benzene; ALS

1-[1,2,4]Triazol-1-ylethanone + Aniline = Acetamide, N-phenyl- + 1H-1,2,4-Triazole

By formula: C4H5N3O + C6H7N = C8H9NO + C2H3N3

Quantity Value Units Method Reference Comment
Deltar-72.3 ± 0.3kJ/molCmWadso, 1962solid phase; ALS

Lithium ion (1+) + 1H-1,2,4-Triazole = (Lithium ion (1+) bullet 1H-1,2,4-Triazole)

By formula: Li+ + C2H3N3 = (Li+ bullet C2H3N3)

Quantity Value Units Method Reference Comment
Deltar191. ± 7.9kJ/molCIDTRodgers and Armentrout, 2000RCD

Potassium ion (1+) + 1H-1,2,4-Triazole = (Potassium ion (1+) bullet 1H-1,2,4-Triazole)

By formula: K+ + C2H3N3 = (K+ bullet C2H3N3)

Quantity Value Units Method Reference Comment
Deltar87.0 ± 5.0kJ/molCIDTRodgers and Armentrout, 2000RCD

Gas phase ion energetics data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Ion clustering data, Mass spectrum (electron ionization), 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)886.0kJ/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Gas basicity855.9kJ/molN/AHunter and Lias, 1998HL

Ionization energy determinations

IE (eV) Method Reference Comment
9.8PEPalmer, Simpson, et al., 1981LLK
10.1PEPalmer, Simpson, et al., 1981Vertical value; LLK
10.6PEGuimon, Pfister-Guillouzo, et al., 1980Vertical value; LLK
10.0PECradock, Findlay, et al., 1973Vertical value; LLK

De-protonation reactions

C2H2N3- + Hydrogen cation = 1H-1,2,4-Triazole

By formula: C2H2N3- + H+ = C2H3N3

Quantity Value Units Method Reference Comment
Deltar1440. ± 8.8kJ/molG+TSTaft, 1991gas phase; B
Quantity Value Units Method Reference Comment
Deltar1410. ± 8.4kJ/molIMRETaft, 1991gas phase; B

Ion clustering data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, Mass spectrum (electron ionization), 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: Robert C. Dunbar

Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. Searches may be limited to ion clustering reactions. A general reaction search form is also available.

Clustering reactions

Potassium ion (1+) + 1H-1,2,4-Triazole = (Potassium ion (1+) bullet 1H-1,2,4-Triazole)

By formula: K+ + C2H3N3 = (K+ bullet C2H3N3)

Quantity Value Units Method Reference Comment
Deltar87.0 ± 5.0kJ/molCIDTRodgers and Armentrout, 2000 

Lithium ion (1+) + 1H-1,2,4-Triazole = (Lithium ion (1+) bullet 1H-1,2,4-Triazole)

By formula: Li+ + C2H3N3 = (Li+ bullet C2H3N3)

Quantity Value Units Method Reference Comment
Deltar191. ± 7.9kJ/molCIDTRodgers and Armentrout, 2000 

Sodium ion (1+) + 1H-1,2,4-Triazole = (Sodium ion (1+) bullet 1H-1,2,4-Triazole)

By formula: Na+ + C2H3N3 = (Na+ bullet C2H3N3)

Quantity Value Units Method Reference Comment
Deltar124. ± 5.0kJ/molCIDTRodgers and Armentrout, 2000 

Free energy of reaction

DeltarG° (kJ/mol) T (K) Method Reference
0.00.CIDTRodgers and Armentrout, 2000

Mass spectrum (electron ionization)

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering 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

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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-5086
NIST MS number 230199

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References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering data, Mass spectrum (electron ionization), Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Jimenez, Roux, et al., 1989
Jimenez, P.; Roux, M.V.; Turrion, C., Thermochemical properties of N-heterocyclic compounds II. Enthalpies of combustion, vapour pressures, enthalpies of sublimation, and enthalpies of formation of 1,2,4-triazole and benzotriazole, J. Chem. Thermodyn., 1989, 21, 759-764. [all data]

Faour and Akasheh, 1985
Faour, M.; Akasheh, T.S., Heat of combustion of some N-heterocycle compounds. Part 1, J. Chem. Soc. Perkin Trans. 2, 1985, 811-713. [all data]

Masalitinova, Oleinikova, et al., 1984
Masalitinova, T.N.; Oleinikova, T.P.; Polyakova, L.P., Thermochemical study of 1,2,4-triazole as a reference substnace for the calorimetry of combustion of organonitrogen compounds, Ref. Zh., Khim.; Abstr. No. 7B3028, 1984, 0. [all data]

Aleksandrov, Osipova, et al., 1982
Aleksandrov, Yu.I.; Osipova, T.R.; Yuhkevich, V.F., Study of 1,2,4-triazole as a standard sample in the calorimetry of thoroughly nitrided organic compounds, Termodin. Organ. Soedin., 1982, 42-45. [all data]

Zimmerman and Geisenfelder, 1961
Zimmerman, H.; Geisenfelder, H., Uber die Mesomerieenergie von Azolen, Z. Electrochem., 1961, 65, 368-371. [all data]

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]

Taft, 1991
Taft, R.W., , personal communication, Aug, 1991. [all data]

Rodgers and Armentrout, 2000
Rodgers, M.T.; Armentrout, P.B., Noncovalent Metal-Ligand Bond Energies as Studied by Threshold Collision-Induced Dissociation, Mass Spectrom. Rev., 2000, 19, 4, 215, https://doi.org/10.1002/1098-2787(200007)19:4<215::AID-MAS2>3.0.CO;2-X . [all data]

Wadso, 1960
Wadso, I., Heats of hydrolysis of N-acetylated imidazole, 1,2,4-triazole and tetrazole, Acta Chem. Scand., 1960, 14, 903-908. [all data]

Wadso, 1962
Wadso, I., Heats of aminolysis and hydrolysis of some N-acetyl compounds and of acetic anhydride, Acta Chem. Scand., 1962, 16, 471-478. [all data]

Mauret, Fayet, et al., 1973
Mauret, P.; Fayet, J.P.; Fabre, M.; Elguero, J.; Pardo, M.d.C., Tautomerism study of «upsilon»-triazole from dipolar moment measurements, J. Chim. Phys. Phys.-Chim. Biol., 1973, 70, 1483-1485. [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]


Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering data, Mass spectrum (electron ionization), References