ABSORPTION, CIRCULAR-DICHROISM, AND LUMINESCENCE SPECTROSCOPY OF ELECTROGENERATED DELTA-[RU(BIPY)(3)](+ 0/-) AND DELTA-[OS(BIPY)(3)](+/0/-)(BIPY=2,2'-BIPYRIDINE)/

The electronic absorption and circular dichroism (CD) spectra of the c omplexes produced by the one, two, and three electron reduction of Del ta-[Ru(bipy)(3)](2+) and Delta-[Os(bipy)(3)](2+) are reported. The CD spectra give unequivocal proof that the added electrons are localized on individual bipiridine ligands and thus that the complexes are corre ctly formulated [M(bipy)(2)(bipy(-))](+), [M(bipy)(bipy(-))(2)](0), an d [M(bipy(-))(3)](-). The absorption spectra of the triply reduced spe cies [M(bipy(-))(3)](-) (M = Ru, Os) are compared to those of the Fe-I I and Ir-III analogs. The luminescence spectra of the two triply reduc ed complexes [Ru(bipy(-))(3)](-) and [Os(bipy(-))(3)](-). are also pre sented. The MLCT luminescence found in the parent complexes is complet ely quenched and is replaced by a weak luminescence attributed to the pi(10) --> pi(7) transition of the (coordinated) [bipy](-) ion.