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
  • Vibrational and/or electronic energy levels
  • References
  • Notes
• Other data available:
  • Gas phase ion energetics data
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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

Vibrational and/or electronic energy levels

Go To: Top, Gas phase 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: Marilyn E. Jacox

State:   X

Additional references: Jacox, 1994, page 378; Jacox, 1998, page 338; Jacox, 2003, page 355

Notes

References

Go To: Top, Gas phase thermochemistry data, Vibrational and/or electronic energy levels, Notes

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]

Arnold, Radziszewski, et al., 1991
Arnold, B.R.; Radziszewski, J.G.; Campion, A.; Perry, S.S.; Michl, J., The Raman spectrum of matrix-isolated cyclobutadiene. Evidence for environmental hindrance to heavy-atom tunneling?, J. Am. Chem. Soc., 1991, 113, 2, 692, https://doi.org/10.1021/ja00002a058 . [all data]

Maier, 1988
Maier, G., Tetrahedran und Cyclobutadien, Angew. Chem., 1988, 100, 3, 317, https://doi.org/10.1002/ange.19881000304 . [all data]

Orendt, Arnold, et al., 1988
Orendt, A.M.; Arnold, B.R.; Radziszewski, J.G.; Facelli, J.C.; Malsch, K.D.; Strub, H.; Grant, D.M.; Michl, J., Carbon-13 NMR and polarized IR spectra of vicinally labeled cyclobutadiene-13C2 in an argon matrix: interconversion of valence tautomers, J. Am. Chem. Soc., 1988, 110, 8, 2648, https://doi.org/10.1021/ja00216a049 . [all data]

Arnold and Michl, 1993
Arnold, B.R.; Michl, J., Ultraviolet and polarized infrared spectroscopy of matrix-isolated cyclobutadiene and its isotopomers, J. Phys. Chem., 1993, 97, 50, 13348, https://doi.org/10.1021/j100152a046 . [all data]

Masamune, Souto-Bachiller, et al., 1978
Masamune, S.; Souto-Bachiller, F.A.; Machiguchi, T.; Bertie, J.E., Cyclobutadiene is not square, J. Am. Chem. Soc., 1978, 100, 15, 4889, https://doi.org/10.1021/ja00483a043 . [all data]

Chapman, McIntosh, et al., 1973
Chapman, O.L.; McIntosh, C.L.; Pacansky, J., Photochemical transformations. XLVIII. Cyclobutadiene, J. Am. Chem. Soc., 1973, 95, 2, 614, https://doi.org/10.1021/ja00783a066 . [all data]

Lin and Krantz, 1972
Lin, C.Y.; Krantz, A., J. Chem. Soc., 1972, Chem. Commun. 1111. [all data]

Maier, Hartan, et al., 1976
Maier, G.; Hartan, H.-G.; Sayrac, T., Cyclobutadien --- ein quadratisches Singulett-Molekül?, Angew. Chem., 1976, 88, 8, 252, https://doi.org/10.1002/ange.19760880805 . [all data]

Maier and Lautz
Maier, G.; Lautz, C., Eur. J. Org. Chem. 1998, 769.. [all data]

Jacox, 1994
Jacox, M.E., Vibrational and electronic energy levels of polyatomic transient molecules, American Chemical Society, Washington, DC, 1994, 464. [all data]

Jacox, 1998
Jacox, M.E., Vibrational and electronic energy levels of polyatomic transient molecules: supplement A, J. Phys. Chem. Ref. Data, 1998, 27, 2, 115-393, https://doi.org/10.1063/1.556017 . [all data]

Jacox, 2003
Jacox, M.E., Vibrational and electronic energy levels of polyatomic transient molecules: supplement B, J. Phys. Chem. Ref. Data, 2003, 32, 1, 1-441, https://doi.org/10.1063/1.1497629 . [all data]

Notes

Go To: Top, Gas phase thermochemistry data, Vibrational and/or electronic energy levels, 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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