Properties of excited states and one-electron reduced forms of Ruthenium(II)-diimine photosensitizers

In this paper we compare the spectral, acid-base, electrochemical, and kinetic properties of the excited states and one-electron reduced forms of homo- and heteroleptic Ru(II)-diimine photosensitizers that contain 2,2’-bipyridine, 2,2’-bipyrazine, and 2,2’-bipyrimidine ligands. These species, represented as *(RuIIIL.-)2+ and (RuIIL.-)+, respectively, are orbital analogues in that the intra- or intermolecularly transferred electron resides on the same uniquely reduced ligand. The variations in the properties of these species, resulting from changes in the coordinating ligands, permit the fine-tuning of photochemical systems.