1H-Tetrazole

• Formula: CH₂N₄
• Molecular weight: 70.0534
• IUPAC Standard InChI: InChI=1S/CH2N4/c1-2-4-5-3-1/h1H,(H,2,3,4,5) Copy

  
• IUPAC Standard InChIKey: KJUGUADJHNHALS-UHFFFAOYSA-N Copy
• CAS Registry Number: 288-94-8
• 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:
  • 2H-Tetrazole
• Other names: Tetraazacyclopentadiene; Tetrazole
• Information on this page:
  • 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 at other public NIST sites:
  • Gas Phase Kinetics Database
• Options:
  • Switch to SI units

Data at NIST subscription sites:

• NIST / TRC Web Thermo Tables, professional edition (thermophysical and thermochemical data)

NIST subscription sites provide data under the NIST Standard Reference Data Program, but require an annual fee to access. The purpose of the fee is to recover costs associated with the development of data collections included in such sites. Your institution may already be a subscriber. Follow the links above to find out more about the data in these sites and their terms of usage.

Gas phase thermochemistry data

Go To: Top, 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 as indicated in comments:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DRB - Donald R. Burgess, Jr.

Condensed phase thermochemistry data

Go To: Top, Gas 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 as indicated in comments:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DH - Eugene S. Domalski and Elizabeth D. Hearing

Constant pressure heat capacity of solid

Phase change data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry 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 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
DRB - Donald R. Burgess, Jr.
AC - William E. Acree, Jr., James S. Chickos
DH - Eugene S. Domalski and Elizabeth D. Hearing

Enthalpy of sublimation

Enthalpy of fusion

Enthalpy of phase transition

Entropy of phase transition

Reaction thermochemistry data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change 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 as indicated in comments:
B - John E. Bartmess
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

CHN₄^- +  =

By formula: CHN₄^- + H⁺ = CH₂N₄

 +  =  + 

By formula: C₃H₄N₄O + H₂O = CH₂N₄ + C₂H₄O₂

 +  =  + 

By formula: C₃H₄N₄O + C₆H₇N = C₈H₉NO + CH₂N₄

Gas phase ion energetics data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry 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
LL - Sharon G. Lias and Joel F. Liebman
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi

Ionization energy determinations

De-protonation reactions

CHN₄^- +  =

By formula: CHN₄^- + H⁺ = CH₂N₄

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, 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

Spectrum

Notice: This spectrum may be better viewed with a Javascript and HTML 5 enabled browser.

For Zoom

1.) Enter the desired X axis range (e.g., 100, 200)

2.) Check here for automatic Y scaling

3.) Press here to zoom

Additional Data

References

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), Notes

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

Balepin, Lebedev, et al., 1977
Balepin, A.A.; Lebedev, V.P.; Miroshnichenko, E.A.; Koldobskii, G.I.; Ostovskii, V.A.; Larionov, B.P.; Gidaspov, B.V.; Lebedev, Yu.A., Energy effects in polyphenylenes and phenyltetrazoles, Svoistva Veshchestv Str. Mol., 1977, 93-98. [all data]

McEwan and Rigg, 1951
McEwan, W.S.; Rigg, M.W., The heats of combustion of compounds containing the tetrazole ring, J. Am. Chem. Soc., 1951, 73, 4725-4727. [all data]

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

Kabo, Kozyro, et al., 1993
Kabo, G.J.; Kozyro, A.A.; Krasulin, A.P.; Sevruk, V.M.; Ivashkevich, L.S., Thermodynamic properties and tautomerism of tetrazole, J. Chem. Thermodynam., 1993, 25, 485-493. [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]

Kabo, Kozyro, et al., 1993, 2
Kabo, G.Ya.; Kozyro, A.A.; Krasulin, A.P.; Sevruk, V.M.; Ivashkevich, L.S., Thermodynamic properties and tautomerism of tetrazole, J. Chem. Thermodyn., 1993, 25, 485. [all data]

Kozyro, Simirskii, et al., 1990
Kozyro, A.A.; Simirskii, V.V.; Kabo, G.Y.; Frenkel, M.L.; Krasulin, A.P.; Sevruk, V.M.; Sokolov, N.A., Additivity of the thermochemical characteristics of tetraalklyl-substituted carbamides, Zh. Fiz. Khim., 1990, 64, 2360. [all data]

Kozyro, Simirskii, et al., 1990, 2
Kozyro, A.A.; Simirskii, V.V.; Krasulin, A.P.; Sevruk, V.M.; Kabo, G.Y.; Frenkel, M.L.; Gaponik, P.N.; Grigor'ev, Y.V., Russ. J. Phys. Chem., 1990, 64, 348. [all data]

Cox and Pilcher, 1970
Cox, J.D.; Pilcher, G., Thermochemistry of Organic and Organometallic Compounds, Academic Press Inc., London, 1970, 643. [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]

Kozyro, Simirskii, et al., 1990, 3
Kozyro, A.A.; Simirskii, V.V.; Krasulin, A.P.; Sevruk, V.M.; Kabo, G.Y.; Frenkel, M.L.; Gaponik, P.N.; Grigor'ev, Y.V., Thermodynamic properties of tetrazole derivatives in different aggregation states, Zh. Fiz. Khim., 1990, 64, 656. [all data]

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

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, Khayar, et al., 1989
Guimon, C.; Khayar, S.; Gracian, F.; Begtrup, M.; Pfister-Guillouzo, G., HeI photoelectron and theoretical study of the gas phase flash pyrolysis of tetrazole and analysis of CN₂H₂ energy hypersurface, Chem. Phys., 1989, 138, 157. [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, Mass spectrum (electron ionization), References

• Symbols used in this document:
  

  Cp,solid	Constant pressure heat capacity of solid
  S°solid,1 bar	Entropy of solid at standard conditions (1 bar)
  Tfus	Fusion (melting) point
  Ttriple	Triple point temperature
  ΔHtrs	Enthalpy of phase transition
  ΔStrs	Entropy of phase transition
  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
  ΔfusH	Enthalpy of fusion
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔsubH	Enthalpy of sublimation
  ΔsubH°	Enthalpy of sublimation at standard conditions

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
• The National Institute of Standards and Technology (NIST) uses its best efforts to deliver a high quality copy of the Database and to verify that the data contained therein have been selected on the basis of sound scientific judgment. However, NIST makes no warranties to that effect, and NIST shall not be liable for any damage that may result from errors or omissions in the Database.
• Customer support for NIST Standard Reference Data products.