Spectroscopic and Electrochemical Properties of a Series of Mixed-Metal d6,d8Bimetallic Complexes of the Form [(bpy)2M(BL)PtCl2]2+(bpy = 2,2‘-Bipyridine; BL = dpq (2,3-Bis(2- pyridyl)quinoxaline) or dpb (2,3-Bis(2-pyridyl)- benzoquinoxaline); M = OsIIor RuII)

A series of new polymetallic complexes have been prepared which couple d6 pseudooctahedral lightabsorbing centers to a d8 square planar platinum site. These systems have lowest lying excited states that are M → BL charge transfer in nature. Hence, optical excitation directs charge flow toward the coupled platinum site. Synthetic variation of the lightabsorbing metal and the bridging ligand has been quite useful in the interpretation of the spectroscopic and electrochemical properties of these systems.