| Abstract: | Theoretical Investigations on the Charge Transfer of d6-Metal Complexes with Acceptor Ligands On the basis of the electronic structure of pentaammineruthenium(II) and pentacyanoferrate(II) complexes with aromatic N-heterocyclic ligands L the different tendency of the complex fragments to charge-transfer interactions with acceptor molecules is discussed. The increased energy and the reduced absorption intensity of the metal oxidation band of [Fe(CN)5L]3? are due to the diminished orbital interaction between the pentacyanoferrate(II) fragment and the nitrogen acceptor ligand caused by π-bonding interaction of the central metal with the cyanide co-ligands. The possibility of the variation of the energy of the acceptor levels connected with the position of the MLCT bands of the mixed-ligand complexes has been investigated by numerous azine and α-diimine ligands of different structure. Besides inductive and mesomeric effects the steric influences on the π-acceptor ability of the ligand and on the energy and absorption intensity of the MLCT band are examined. |
