Pyridazine

• Formula: C₄H₄N₂
• Molecular weight: 80.0880
• IUPAC Standard InChI: InChI=1S/C4H4N2/c1-2-4-6-5-3-1/h1-4H Copy

  
• IUPAC Standard InChIKey: PBMFSQRYOILNGV-UHFFFAOYSA-N Copy
• CAS Registry Number: 289-80-5
• 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.
• Other names: Orthodiazine; 1,2-Diazabenzene; 1,2-Diazine
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• Information on this page:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Reaction thermochemistry data
  • References
  • Notes
• Other data available:
  • Phase change data
  • Gas phase ion energetics data
  • IR Spectrum
  • Mass spectrum (electron ionization)
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  • Gas Chromatography
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Gas phase thermochemistry data

Go To: Top, Condensed phase thermochemistry data, Reaction thermochemistry 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: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

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 by: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

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 by: John E. Bartmess

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

C₄H₃N₂^- +  =

By formula: C₄H₃N₂^- + H⁺ = C₄H₄N₂

References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Reaction thermochemistry data, Notes

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

Tjebbes, 1962
Tjebbes, J., The heats of combustion and formation of the three diazines and their resonance energies, Acta Chem. Scand., 1962, 16, 916-921. [all data]

Meot-ner and Kafafi, 1988
Meot-ner, M.; Kafafi, S.A., Carbon Acidities of Aromatic Compounds, J. Am. Chem. Soc., 1988, 110, 19, 6297, https://doi.org/10.1021/ja00227a003 . [all data]

Wren, Vogelhuber, et al., 2012
Wren, S.W.; Vogelhuber, K.M.; Garver, J.M.; Kato, S.; Sheps, L.; Bierbaum, V.M.; Lineberger, W.C., C-H Bond Strengths and Acidities in Aromatic Systems: Effects of Nitrogen Incorporation in Mono-, Di-, and Triazines, J. Am. Chem. Soc., 2012, 134, 15, 6584-6595, https://doi.org/10.1021/ja209566q . [all data]

Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Reaction thermochemistry data, References

• Symbols used in this document:
  

  ΔcH°liquid	Enthalpy of combustion of liquid at standard conditions
  ΔfH°gas	Enthalpy of formation of gas at standard conditions
  ΔfH°liquid	Enthalpy of formation of liquid 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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