Redox behavior of edge-shared bioctahedral (Re2 mu-NCS 2 NCS 8)3- and its relationship to the direct metal-metal-bonded ion (Re2 NCS 8)2-: a spectroelectrochemical study

The redox reactivity of edge-shared bioctahedral (ESBO) (Re2 mu-NCS 2 NCS 8)3- is determined by electrochemical and spectroelectrochemical studies. The dirhenium complex undergoes reversible oxidation and one-electron reduction to yield stable species (Re2 mu-NCS 2 NCS 8)2- and (Re2 mu-NCS 2 NCS 8)4- of similar structure. Further redox reactions result to more reactive species, while two-electron reduction of (Re2 NCS 10)4- yields a new structural conformation in the direct metal-metal-bonded complex (Re2 NCS 8 NCS 2)6- which re-oxidizes back to (Re2 NCS 10)4-.