1H-Imidazole

• Formula: C₃H₄N₂
• Molecular weight: 68.0773
• IUPAC Standard InChI: InChI=1S/C3H4N2/c1-2-5-3-4-1/h1-3H,(H,4,5) Copy

  
• IUPAC Standard InChIKey: RAXXELZNTBOGNW-UHFFFAOYSA-N Copy
• CAS Registry Number: 288-32-4
• Chemical structure:
  This structure is also available as a 2d Mol file or as a computed 3d SD file
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• Other names: Imidazole; Glyoxalin; Glyoxaline; Imidazol; Imutex; Methanimidamide, N,N'-1,2-ethenediyl-; Miazole; 1,3-Diaza-2,4-cyclopentadiene; 1,3-Diazole; Formamidine, N,N'-vinylene-; Iminazole; IMD; Pyrro(b)monazole; USAF EK-4733; NSC 60522
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• Information on this page:
  • Condensed phase thermochemistry data
  • Phase change data
  • IR Spectrum
  • UV/Visible spectrum
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Reaction thermochemistry data
  • Gas phase ion energetics data
  • Ion clustering data
  • Mass spectrum (electron ionization)
  • Gas Chromatography
• Data at other public NIST sites:
  • X-ray Photoelectron Spectroscopy Database, version 5.0
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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

Constant pressure heat capacity of solid

Phase change 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:
BS - Robert L. Brown and Stephen E. Stein
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

Entropy of fusion

IR Spectrum

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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 by: Coblentz Society, Inc.

Condensed Phase Spectrum

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Notice: Except where noted, spectra from this collection were measured on dispersive instruments, often in carefully selected solvents, and hence may differ in detail from measurements on FTIR instruments or in other chemical environments. More information on the manner in which spectra in this collection were collected can be found here.

Notice: Concentration information is not available for this spectrum and, therefore, molar absorptivity values cannot be derived.

Additional Data

UV/Visible spectrum

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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 by: Victor Talrose, Alexander N. Yermakov, Alexy A. Usov, Antonina A. Goncharova, Axlexander N. Leskin, Natalia A. Messineva, Natalia V. Trusova, Margarita V. Efimkina

Spectrum

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Additional Data

References

Go To: Top, Condensed phase thermochemistry data, Phase change data, IR Spectrum, UV/Visible spectrum, Notes

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

Zaheeruddin and Lodhi, 1991
Zaheeruddin, M.; Lodhi, Z.H., Enthalpies of formation of some cyclic compounds, Phys. Chem. (Peshawar Pak.), 1991, 10, 111-118. [all data]

Jimenez, Roux, et al., 1987
Jimenez, P.; Roux, M.V.; Turrion, C., Thermochemical properties of N-heterocyclic compounds. I. Enthalpies of combustion, vapour pressures and enthalpies of sublimation, and enthalpies of formation of pyrazole, imidazole, indazole, and benzimidazole, J. Chem. Thermodyn., 1987, 19, 985-992. [all data]

Jimenez, Roux, et al., 1986
Jimenez, P.; Roux, M.V.; Turrion, C.; Gomis, F., Thermochemical properties of some N-heterocyclic compounds, J. Calorim. Anal. Therm. Thermodyn. Chim., 1986, 17, 469-470. [all data]

Bedford, Edmondson, et al., 1962
Bedford, A.F.; Edmondson, P.B.; Mortimer, C.T., Heats of formation and bond energies. Part VI. n-Butyliso-butyraldimine, n-butylisobutylamine, pyrazole, and imidazole, J. Chem. Soc., 1962, 2927-2931. [all data]

Cox and Pilcher, 1970
Cox, J.D.; Pilcher, G., Thermochemistry of Organic and Organometallic Compounds, Academic Press, New York, 1970, 1-636. [all data]

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

DeWit, DeKruif, et al., 1983
DeWit, H.G.M.; DeKruif, C.G.; Van Miltenburg, J.C., Thermodynamic properties of molecular organic crystals containing organic crystals containing nitrogen, oxygen, and sulfur. II. Molar heat capacities of eight compounds by adiabatic calorimetry, J. Chem. Thermodynam., 1983, 15, 891-902. [all data]

DeWit, Offringa, et al., 1983
DeWit, H.G.M.; Offringa, J.C.A.; De Kruif, C.G.; Van Miltenburg, J.C., Thermodynamic properties of molecular organic crystals containing nitrogen, oxygen and sulfur. III. Molar heat capacities measured by differential scanning calorimetry, Thermochim. Acta, 1983, 65, 43-51. [all data]

Weast and Grasselli, 1989
CRC Handbook of Data on Organic Compounds, 2nd Editon, Weast,R.C and Grasselli, J.G., ed(s)., CRC Press, Inc., Boca Raton, FL, 1989, 1. [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]

De Wit, Offringa, et al., 1983
De Wit, H.G.M.; Offringa, J.C.A.; De Kruif, C.G.; van Miltenburg, J.C., Thremodynamic properties of molecular organic crystals containing nitrogen, oxygen and sulfur. III. molar heat capacities measured by DSC. scanning calorimetry., Thermochim. Acta, 1983, 65, 43. [all data]

De Wit, De Kruif, et al., 1983
De Wit, H.G.M.; De Kruif, C.G.; Van Miltenburg, J.C., Thermodynamic properties of molecular organic crystals containing nitrogen, oxygen, and sulfur II. Molar heat capacities of eight compounds by adiabatic calorimetry, J. Chem. Thermodyn., 1983, 15, 9, 891, https://doi.org/10.1016/0021-9614(83)90095-2 . [all data]

De Wit, Van Miltenburg, et al., 1983
De Wit, H.G.M.; Van Miltenburg, J.C.; De Kruif, C.G., Thermodynamic properties of molecular organic crystals containing nitrogen, oxygen, and sulphur 1. Vapour pressures and enthalpies of sublimation, The Journal of Chemical Thermodynamics, 1983, 15, 7, 651-663, https://doi.org/10.1016/0021-9614(83)90079-4 . [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]

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]

De Wit, De Kruif, et al., 1983, 2
De Wit, H.G.M.; De Kruif, C.G.; Van Miltenburg, J.C., Thermodynamic properties of molecular organic crystals containing nitrogen, oxygen, and sulfur II. Molar heat capacities of eight compounds by adiabatic calorimetry, The Journal of Chemical Thermodynamics, 1983, 15, 9, 891-902, https://doi.org/10.1016/0021-9614(83)90095-2 . [all data]

Johnson, 1967
Johnson, E.A., UV atlas of organic compounds, 1967, 3, G1/7. [all data]

Notes

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• Symbols used in this document:
  

  Cp,solid	Constant pressure heat capacity of solid
  Tboil	Boiling point
  Tfus	Fusion (melting) point
  Ttriple	Triple point temperature
  ΔcH°solid	Enthalpy of combustion of solid at standard conditions
  ΔfH°solid	Enthalpy of formation of solid at standard conditions
  ΔfusH	Enthalpy of fusion
  ΔfusS	Entropy of fusion
  ΔsubH	Enthalpy of sublimation
  ΔsubH°	Enthalpy of sublimation at standard conditions

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