Cyclobutadiene

• Formula: C₄H₄
• Molecular weight: 52.0746
• IUPAC Standard InChI: InChI=1S/C4H4/c1-2-4-3-1/h1-4H Copy

  
• IUPAC Standard InChIKey: HWEQKSVYKBUIIK-UHFFFAOYSA-N Copy
• CAS Registry Number: 1120-53-2
• Chemical structure:
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• Information on this page:
  • Gas phase thermochemistry data
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Vibrational and/or electronic energy levels
• Data at other public NIST sites:
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Gas 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: Glushko Thermocenter, Russian Academy of Sciences, Moscow

Constant pressure heat capacity of gas

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:
LL - Sharon G. Lias and Joel F. Liebman
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron

View reactions leading to C₄H₄⁺ (ion structure unspecified)

Ionization energy determinations

References

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

Dorofeeva O.V., 1986
Dorofeeva O.V., Thermodynamic properties of twenty-one monocyclic hydrocarbons, J. Phys. Chem. Ref. Data, 1986, 15, 437-464. [all data]

Kohn and Chen, 1993
Kohn, D.W.; Chen, P., Vibrational structure in the photoelectron spectrum of cyclobutadiene as a probe of structure, J. Am. Chem. Soc., 1993, 115, 2844. [all data]

Li and McGee, 1969
Li, P.H.; McGee, H.A., Jr., Mass spectrum and ionization potential of condensed cyclobutadiene, Chem. Commun., 1969, 592. [all data]

Hedaya, Miller, et al., 1969
Hedaya, E.; Miller, R.D.; McNeil, D.W.; D'Angelo, P.F.; Schissel, P., Flash vacuum pyrolysis. V. Cyclobutadiene, J. Am. Chem. Soc., 1969, 91, 1875. [all data]

Dewar and Worley, 1969
Dewar, M.J.S.; Worley, S.D., Photoelectron spectra of molecules. I. Ionization potentials of some organic molecules and their interpretation, J. Chem. Phys., 1969, 50, 654. [all data]

Kreile, Munzel, et al., 1986
Kreile, J.; Munzel, N.; Schweig, A.; Specht, H., UV Photoelectron spectrum of cyclobutadiene. Free cyclobutadiene stable up to high temperatures, Chem. Phys. Lett., 1986, 124, 140. [all data]

Notes

Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, References

• Symbols used in this document:
  

  Cp,gas

  Constant pressure heat capacity of gas

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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