The photoelectron spectroscopy and electronic structure of metal β-diketonates and their analogs

He(I) photoelectron spectra of transition and non-transition metal bis- and tris-beta-diketonate complexes were studied. Spectra have been interpreted based on the study of regularities in spectra of compound rows and results of quantum chemical calculations of ground and ionized states by X-alpha-DV and ab initio methods. In group III d-metal complexes, the bond covalency changes in the sequence YL3 < LuL3 < ScL3, whereas for complexes of final elements in the transition row, the bond covalency is directly proportional to the period row. Ionization energy changes for O to NR group substitution, gamma-H to Cl and CH3 group, beta-CH3 groups to H, C(CH3) and C6H5, are discussed. It was shown that for high-spin complexes, despite the closeness of the final state energies, psi-function symmetry prohibits the interaction between states caused by d- and L-electrons removal. (C) 1998 Elsevier Science B.V.