Optical electron transfer in the symmetrical, mixed-valence dimer [(NH3)5RuII(4,4/-bpy)RuIII(NH3)5]5+(4,4/-bpy is 4,4'-bipyridine) has been examined in mixtures of acetonitrile and dimethyl sulfoxide (Me2SO) as solvent. From spectral and electrochemical measurements evidence was found for strong selective solvation by Me2SO. For the metal-to-metal charge-transfer transition, unexpectedly large energetic effects were observed for the Me2SO mole fraction range between 0 and ~0.1. The energetic effects were found to result from unsymmetrical secondary coordination for (NH3)5RuIIIvs. (NH3)5RuII. The appearance of such effects suggests the existence of parallel rate effects for related thermal self-exchanges.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Inorganic Chemistry