Spectroscopic and structural properties of binuclear platinum-terpyridine complexes

Binuclear platinum-terpyridine (tpy) complexes have been prepared with a variety of bridging ligands resulting in a range of metal-metal distances (2.998(2) to 3.342(3) A). The energy of an intense visible absorption is strongly dependent on this metal-metal separation and is assigned to a d sigma *(Pt2) yield pi*(tpy) transition.