Salt effects on the electron transfer transition within the binuclear complex [(NH3)5RuIII(μ-CN)FeII(CN)5]−

Abstract

By a combination of spectroscopic and electrochemical techniques the reorganization and reaction free energies of the intramolecular electron transfer within the binuclear complex [(NH₃)₅Ru^III–NC–Fe^II(CN)₅]⁻ in different salt solutions were obtained. It is concluded that the variations of these parameters, as well as those in the energy of the maximum of the metal-to-metal charge transter (MMCT) band, are caused by ion pairing of the binuclear complex with the ions of the electrolytes. Also demonstrated was that the static, optical and electrochemical data permit reliable obtention of the activation free energies of the thermal electron transfer reactions.