MADE-TO-ORDER CONTROL OF THE DIRECTION OF ELECTRONIC-ENERGY TRANSFER IN TETRANUCLEAR LUMINESCENT METAL-COMPLEXES

We have synthesized the tetranuclear complexes Ru[(mu-2,3-dpp)Ru(bpy)2]2[(mu-2,3-dpp)Ru(biq)2]8+ and Ru[(mu-2,3-dpp)Ru(bpy)2]2[(mu-2,3-dpp)Os(bpy)2]8+ which belong to the M[(BL)M(L)2]3(8+) family (M = Ru2+ or Os2+; BL = 2,3-dpp or 2,5-dpp; L = bpy or biq; dpp = bis(2-pyridyl)pyrazine; bpy = 2,2'-bipyridine; biq = 2,2'-biquinoline). Luminescence investigations show that in the complexes of this family the electronic energy originated upon light absorption can be channelled in any desired direction along the supramolecular structure by a suitable choice of M, L, and BL.