Cyclopentadienyl radical

• Formula: C₅H₅
• Molecular weight: 65.0932
• IUPAC Standard InChI: InChI=1S/C5H5/c1-2-4-5-3-1/h1-5H Copy

  
• IUPAC Standard InChIKey: HPYIUKIBUJFXII-UHFFFAOYSA-N Copy
• CAS Registry Number: 2143-53-5
• Chemical structure:
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• Information on this page:
  • Vibrational and/or electronic energy levels
  • References
  • Notes
• Other data available:
  • Gas phase ion energetics data
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Vibrational and/or electronic energy levels

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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: Marilyn E. Jacox

State:   A

State:   X

Additional references: Jacox, 1994, page 385; Jacox, 1998, page 344; Jacox, 2003, page 364; Liebling and McConnell, 1965; DiMauro, Heaven, et al., 1986

Notes

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.

Thrush, 1956
Thrush, B.A., Spectrum of the Cyclopentadienyl Radical, Nature, 1956, 178, 4525, 155, https://doi.org/10.1038/178155a0 . [all data]

Porter and Ward, 1968
Porter, G.; Ward, B., The Photolytic Preparation of Cyclopentadienyl and Phenyl Nitrene from Benzene Derivatives, Proc. Roy. Soc. (London) A303, 1968, 303, 1473, 139, https://doi.org/10.1098/rspa.1968.0044 . [all data]

Engleman and Ramsay, 1970
Engleman, R., Jr.; Ramsay, D.A., Electronic absorption spectrum of the cyclopentadienyl radical (C, Can. J. Phys., 1970, 48, 8, 964, https://doi.org/10.1139/p70-125 . [all data]

Nelson, Pasternack, et al., 1983
Nelson, H.H.; Pasternack, L.; McDonald, J.R., Excitation and emission spectra of the 2A´´2 «8637» → 2E´´1 system of the gas-phase cyclopentadienyl radical, Chem. Phys., 1983, 74, 2, 227, https://doi.org/10.1016/0301-0104(83)80025-1 . [all data]

Yu, Foster, et al., 1988
Yu, L.; Foster, S.C.; Williamson, J.M.; Heaven, M.C.; Miller, T.A., Rotationally resolved electronic spectrum of jet-cooled cyclopentadienyl radical, J. Phys. Chem., 1988, 92, 15, 4263, https://doi.org/10.1021/j100326a004 . [all data]

Sun and Bernstein, 1995
Sun, S.; Bernstein, E.R., Vibronic structure of the cyclopentadienyl radical and its nonrigid van der Waals cluster with nitrogen, J. Chem. Phys., 1995, 103, 11, 4447, https://doi.org/10.1063/1.470633 . [all data]

Applegate, Bezant, et al., 2001
Applegate, B.E.; Bezant, A.J.; Miller, T.A., The Jahn--Teller and related effects in the cyclopentadienyl radical. II. Vibrational analysis of the A [sup 2]A[sub 2][sup ´´]--X [sup 2]E[sub 1][sup ´´] electronic transition, J. Chem. Phys., 2001, 114, 11, 4869, https://doi.org/10.1063/1.1348276 . [all data]

Yu, Williamson, et al., 1989
Yu, L.; Williamson, J.M.; Miller, T.A., Rotationally resolved electronic spectrum of jet-cooled deuterated cyclopentadienyl radical, Chem. Phys. Lett., 1989, 162, 6, 431, https://doi.org/10.1016/0009-2614(89)87003-4 . [all data]

Korolev and Nefedov, 1993
Korolev, V.A.; Nefedov, O.M., Izv. Akad. Nauk, 1993, Ser. Khim., 1497. [all data]

Engelking and Lineberger, 1977
Engelking, P.C.; Lineberger, W.C., Laser photoelectron spectrometry of C₅H₅-: A determination of the electron affinity and Jahn-Teller coupling in cyclopentadienyl, J. Chem. Phys., 1977, 67, 1412. [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]

Liebling and McConnell, 1965
Liebling, G.R.; McConnell, H.M., Study of Molecular Orbital Degeneracy in C5H5, J. Chem. Phys., 1965, 42, 11, 3931, https://doi.org/10.1063/1.1695862 . [all data]

DiMauro, Heaven, et al., 1986
DiMauro, L.F.; Heaven, M.; Miller, T.A., Lifetimes of the lowest excited states of the cyclopentadienyl and the monomethylcyclopentadienyl radicals, Chem. Phys. Lett., 1986, 124, 6, 489, https://doi.org/10.1016/0009-2614(86)85061-8 . [all data]

Notes

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