Electronic Structure of Metallocene Compounds. 3. Comparison of the

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J. Am. Chem. SOC.1982, 104, 1491-1506

Electronic Structure of Metallocene Compounds. 3. Comparison of the Results of Multiple-Scattering X a Calculations with Various Electronic Observables of Cobaltocene Jacques Weber,*lg Annick Goursot,lb Edouard P6nigault,lb John H. Ammeter,lc and Jurg BachmannlC Contribution from the Section de Chimie. UniuersitP de Gendue, 1211 Gendue 4 , Switzerland, the Laboratoire de Photochimie GPnZrale (E.R.A.No. 386), Ecole Nationale SupPrieure de Chimie de Mulhouse, 68093 Mulhouse Cedex, France, and the Anorganisch- Chemisches Institut, Uniuersitat Zurich, 8057 Zurich, Switzerland. Received June 1I , 1981

Abstract: Theoretical and experimental investigations are reported for cobaltocene Cp2Co (Cp = $-cyclopentadienyl), with the purpose of comparing as many electronic observables as possible with the corresponding expectation values calculated by the multiple-scattering Xa method. Particular emphasis has been placed on the study of the electronic structure, spectroscopic properties, and magnetic interactions of this compound. In agreement with experimental evidence, the ordering of the penultimate orbitals of the *E,, ground state (D5,,notation) is calculated as 4als(Lr) < ... < 4a2”(Lr)