Tuning the Energy of the NIR Absorption of Dinuclear Triphos-Cobalt-Complexes

Z. Naturforsch. 54 b, 1147-1154 (1999); received June 2, 1999 Dinuclear Complexes, NIR Dyes, Cobalt, Tripodal Ligands, Bridging Ligands Dinuclear Co(III) complexes of the type [(triphos)Co(C6X2Z' Z2Z3Z4)Co(triphos)]2+ (Z1 ~4 = O, NR, S; R = H, Me; X = H, Cl, Br, I; 1 62+) have been prepared and characterized by MS, IR, NMR, cyclovoltammetric and UV/VIS/NIR measurements and by X-ray analyses (12+, 3a2+ and 42+). Their redox behaviour and the energy of their low energy LMCT bands was studied and compared to the properties of the mononuclear complexes [(triphos)Co(C6H4Z 'Z 2)]+ (Z1-2 = O, NH, S).