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)
- 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
- Information on this page:
- Other data available:
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Gas phase thermochemistry data
Go To: Top, Condensed phase thermochemistry 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 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 |
|---|---|---|---|---|---|
| ΔfH°gas | 76.6 ± 0.7 | kcal/mol | Ccb | Balepin, Lebedev, et al., 1977 | ALS |
| ΔfH°gas | 76.74 | kcal/mol | N/A | McEwan and Rigg, 1951 | Value computed using ΔfHsolid° value of 237.1 kj/mol from McEwan and Rigg, 1951 and ΔsubH° value of 84.0 kj/mol from Balepin, Lebedev, et al., 1977.; 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 |
|---|---|---|---|---|---|
| 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 |
Reaction 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:
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
| 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 |
+
=
+
By formula: C3H4N4O + H2O = CH2N4 + C2H4O2
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | -10.31 ± 0.09 | kcal/mol | Cm | Wadso, 1960 | solid phase; Heat of hydrolysis; ALS |
+
=
+
By formula: C3H4N4O + C6H7N = C8H9NO + CH2N4
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | -20.22 ± 0.08 | kcal/mol | Cm | Wadso, 1962 | solid phase; ALS |
Gas phase ion energetics 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:
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 |
References
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, 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]
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, Reaction thermochemistry data, Gas phase ion energetics data, 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) 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 ΔrG° Free energy of reaction at standard conditions ΔrH° Enthalpy of reaction at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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