INFLUENCE OF PERIPHERAL LIGANDS ON THE METAL-METAL INTERACTION IN DINUCLEAR METAL-COMPLEXES WITH N-HETEROCYCLIC BRIDGING LIGANDS

Metal-metal interactions, as inferred from comproportionation constants calculated from electrochemical data, have been examined in more than 30 dinuclear metal complexes having N-heterocyclic bridging ligands. It is shown that the peripheral ligands strongly affect the metal-metal electronic coupling. A simple (intuitive) approach shows that the interaction proceeds via an electron or hole transfer mechanism depending on the electronic properties of both bridging and peripheral ligands. Although the proposed view is essentially qualitative, the results are of interest for the design of systems featuring switchable electron and energy transfer processes. Novel possibilities for controlling metal-metal interaction are also proposed.