查看文章

The blue dimer, cis,cis-[(bpy)₂(H₂O)Ru^IIIORu^III(H₂O)(bpy)₂]⁴⁺, is the first designed, well-defined molecule known to function as a catalyst for water oxidation. It meets the stoichiometric requirements for water oxidation, 2H₂O O−O, by utilizing proton-coupled electron-transfer (PCET) reactions in which both electrons and protons are transferred. This avoids charge buildup, allowing for the accumulation of multiple oxidative equivalents at the Ru−O−Ru core. PCET and pathways involving coupled electron–proton transfer (EPT) are also used to avoid high-energy intermediates. Application of density functional theory calculations to molecular and electronic structure supports the proposal of strong electronic coupling across the μ-oxo bridge. The results of this analysis provide explanations for important details of the descriptive chemistry. Stepwise e⁻/H⁺ loss leads to the higher oxidation states [(bpy)₂(O)Ru^V …