The electron relaxation and UP spectra of metal coordination compounds

The electronic structure of 3d-metals bis and tris-beta-diketonates was stu died by methods of UP spectroscopy and quantum chemistry in ab initio, X al pha-DV and INDO approximations. According to PE data, the covalent interact ion metal-legand is realized, on the whole, by n-electrons, and IE1 in all compounds caused by d-electrons. The X alpha-DV calculations give a good ag reement with experimental picture of interaction of metal AOs and ligand or bitals. Ab initio calculations showed the main role of high sigma-orbitals in covalent interaction. All quantum chemical methods overstate multiplet s plitting of ligand levels caused by overestimation of a delocalization fact or of d-electrons. (C) 1998 Elsevier Science B.V. All rights reserved.