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Cyclopentadienyl radical


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


 Energy 
 (cm-1
 Med.   Transition   «lambda»min 
 (nm) 
 «lambda»max 
 (nm) 
 References

To = 29572.166 ± 0.002 gas A-X 306 395 Thrush, 1956
Porter and Ward, 1968
Engleman and Ramsay, 1970
Nelson, Pasternack, et al., 1983
Yu, Foster, et al., 1988
Sun and Bernstein, 1995
Applegate, Bezant, et al., 2001


Vib. 
sym. 
 No.   Approximate 
 type of mode 
 cm-1   Med.   Method   References

a1' 2 1055 gas LF Sun and Bernstein, 1995
Applegate, Bezant, et al., 2001
e1 8 CH deform. 166 H gas AB LF Thrush, 1956
Porter and Ward, 1968
Engleman and Ramsay, 1970
Yu, Williamson, et al., 1989
Sun and Bernstein, 1995
Applegate, Bezant, et al., 2001
e2' 11 1019 gas LF Sun and Bernstein, 1995
Applegate, Bezant, et al., 2001
12 797 gas AB LF Engleman and Ramsay, 1970
Yu, Williamson, et al., 1989
Sun and Bernstein, 1995
Applegate, Bezant, et al., 2001

State:   X


Vib. 
sym. 
 No.   Approximate 
 type of mode 
 cm-1   Med.   Method   References

a1' 2 1071 gas LF Applegate, Bezant, et al., 2001
a2' 3 1244 gas LF Applegate, Bezant, et al., 2001
a2 4 681 gas LF Applegate, Bezant, et al., 2001
4 661 vs Ar IR Korolev and Nefedov, 1993
e1' 5 CH stretch 3079 w m Ar IR Korolev and Nefedov, 1993
6 1383 m Ar IR Korolev and Nefedov, 1993
7 1001 gas LF Applegate, Bezant, et al., 2001
e1 8 766 H gas LF Applegate, Bezant, et al., 2001
e2' 10 1320 gas LF Applegate, Bezant, et al., 2001
11 1041 gas LF Applegate, Bezant, et al., 2001
12 872 gas PD LF Engelking and Lineberger, 1977
Nelson, Pasternack, et al., 1983
Yu, Williamson, et al., 1989
Applegate, Bezant, et al., 2001
e2 13 861 H gas LF Applegate, Bezant, et al., 2001
14 576 H gas LF Applegate, Bezant, et al., 2001

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

Notes

wWeak
mMedium
vsVery strong
H(1/2)(2nu)
oEnergy separation between the v = 0 levels of the excited and electronic ground states.

References

Go To: Top, 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.

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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