Photoelectron spectroscopy of transition metal complexes. Effect of electron relaxation on spectrum informativity

Orbital ionization energies are compared with the results of ab initio calc ulations for three-atomic linear BeCl2, XeF2, CrCl2 and five-atomic tetrahe dral TiCl4, RuO4 molecules to investigate the effect of electron relaxation in ions on the informativity of photoelectron spectra of molecules and com plex compounds. For all compounds except CrCl2 there is satisfactory agreem ent between theory and experiment in respect of the sequence and character of electronic levels and the orbital nature of chemical bonds. In the serie s of 3d metal tris-beta-diketonates, for metal complexes of the second half of the series there are wide discrepancies between the photoelectron, X-al pha-DV, and ab initio data on the electronic structure of the complexes, wh ich are due to electron relaxation in the ions. The calculations exaggerate the miring of levels between the metal and ligands, since the energy split ting of the corresponding spin-orbitals (spin polarization) considerably ex ceeds the multiplet splitting of states corresponding to a vacancy on the l igand MO estimated from the photoelectron spectra.