1H-Tetrazole
- Formula: CH2N4
- Molecular weight: 70.0534
- IUPAC Standard InChIKey: KJUGUADJHNHALS-UHFFFAOYSA-N
- 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:
- Other names: Tetraazacyclopentadiene; Tetrazole
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Condensed phase thermochemistry data
Go To: Top, 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:
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°solid | 56.4 ± 0.1 | kcal/mol | Ccb | Balepin, Lebedev, et al., 1977 | ALS |
ΔfH°solid | 56.66 | kcal/mol | Ccb | McEwan and Rigg, 1951 | ALS |
Quantity | Value | Units | Method | Reference | Comment |
ΔcH°solid | -218.8 ± 0.1 | kcal/mol | Ccb | Balepin, Lebedev, et al., 1977 | ALS |
ΔcH°solid | -219.0 | kcal/mol | Ccb | Zimmerman and Geisenfelder, 1961 | ALS |
ΔcH°solid | -219.03 ± 0.21 | kcal/mol | Ccb | McEwan and Rigg, 1951 | ALS |
Quantity | Value | Units | Method | Reference | Comment |
S°solid,1 bar | 23.03 | cal/mol*K | N/A | Kabo, Kozyro, et al., 1993 | crystaline, I phase; DH |
Constant pressure heat capacity of solid
Cp,solid (cal/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
18.29 | 298.15 | Kabo, Kozyro, et al., 1993 | crystaline, I phase; T = 5 to 320 K.; DH |
Phase change data
Go To: Top, Condensed phase 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
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
Tfus | 430.7 | K | N/A | Hilgeman, Mouroux, et al., 1989 | Uncertainty assigned by TRC = 0.4 K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Ttriple | 430. | K | N/A | Kabo, Kozyro, et al., 1993, 2 | Crystal phase 1 phase; Uncertainty assigned by TRC = 1. K; TRC |
Ttriple | 429. | K | N/A | Kozyro, Simirskii, et al., 1990 | Uncertainty assigned by TRC = 1. K; Det. with triple heat bridge; TRC |
Quantity | Value | Units | Method | Reference | Comment |
ΔsubH° | 20.2 ± 0.6 | kcal/mol | V | Balepin, Lebedev, et al., 1977 | ALS |
ΔsubH° | 20.1 | kcal/mol | N/A | Balepin, Lebedev, et al., 1977 | DRB |
ΔsubH° | 23.3 | kcal/mol | V | Zimmerman and Geisenfelder, 1961 | ALS |
Enthalpy of sublimation
ΔsubH (kcal/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
21.07 | 353. | C | Kabo, Kozyro, et al., 1993 | AC |
21.0 ± 0.33 | 369. | ME | Kabo, Kozyro, et al., 1993 | AC |
21.0 ± 0.38 | 333. to 404. | ME | Kozyro, Simirskii, et al., 1990, 2 | AC |
23.26 | 333. | V | McEwan and Rigg, 1951 | ALS |
23.3 ± 1.0 | 348. | ME | McEwan and Rigg, 1951 | Based on data from 333. to 363. K. See also Cox and Pilcher, 1970.; AC |
Enthalpy of fusion
ΔfusH (kcal/mol) | Temperature (K) | Reference | Comment |
---|---|---|---|
4.3977 | 430.7 | Hilgeman, Mouroux, et al., 1989, 2 | DH |
4.23 | 432.1 | Kozyro, Simirskii, et al., 1990, 3 | AC |
Enthalpy of phase transition
ΔHtrs (kcal/mol) | Temperature (K) | Initial Phase | Final Phase | Reference | Comment |
---|---|---|---|---|---|
0.00335 | 242.5 | crystaline, II | crystaline, I | Kabo, Kozyro, et al., 1993 | DH |
4.3021 | 430. | crystaline, I | liquid | Kabo, Kozyro, et al., 1993 | DH |
21.071 | 353.1 | crystaline, I | Kabo, Kozyro, et al., 1993 | DH |
Entropy of phase transition
ΔStrs (cal/mol*K) | Temperature (K) | Initial Phase | Final Phase | Reference | Comment |
---|---|---|---|---|---|
0.014 | 242.5 | crystaline, II | crystaline, I | Kabo, Kozyro, et al., 1993 | DH |
10.0 | 430. | crystaline, I | liquid | Kabo, Kozyro, et al., 1993 | DH |
59.8 | 353.1 | crystaline, I | Kabo, Kozyro, et al., 1993 | DH |
Gas phase ion energetics data
Go To: Top, Condensed phase thermochemistry data, Phase change 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
IE (eV) | Method | Reference | Comment |
---|---|---|---|
10.95 | PE | Palmer, Simpson, et al., 1981 | LLK |
11.3 | PE | Guimon, Khayar, et al., 1989 | Vertical value; LL |
11.0 | PE | Palmer, Simpson, et al., 1981 | Vertical value; LLK |
11.3 | PE | Cradock, Findlay, et al., 1973 | Vertical value; LLK |
De-protonation reactions
CHN4- + =
By formula: CHN4- + H+ = CH2N4
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 333.7 ± 2.1 | kcal/mol | G+TS | Taft, 1991 | gas phase; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 326.4 ± 2.0 | kcal/mol | IMRE | Taft, 1991 | gas phase; B |
Mass spectrum (electron ionization)
Go To: Top, Condensed phase thermochemistry data, 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
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 | NIST Mass Spectrometry Data Center, 1998. |
NIST MS number | 291693 |
References
Go To: Top, Condensed phase thermochemistry data, Phase change 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]
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]
Taft, 1991
Taft, R.W.,
, personal communication, Aug, 1991. [all data]
Notes
Go To: Top, Condensed phase thermochemistry data, Phase change 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°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
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