Photoelectron spectroscopy of Ce(η-C5H5)3 -: Accessing two ion states on 4f ionization

Valence PES have been measured for Ce(eta-C5H5)(3) in the gas phase with photon energies of 24-135 eV. Two ion states arising from ionization of the single 4f electron are unambiguously characterized by the intensity behaviour of the associated bands. Assignment is made using a VBCI model where purely ionic components are allowed to mix under configuration interaction. Thus the ground state of the [Ce(eta-C5H5)(3)](+) cation is described as a mixture of two configurations of (1)A(1) symmetry, one with no 4f electron, Lf(0) and one with a single 4f electron interacting strongly with a hole of the same symmetry in the ligand shell, L-T. (c) 2006 Elsevier B.V. All rights reserved.