Reprint of “Theory of chemical bonds in metalloenzymes XVIII. Importance of mixed-valence configurations for Mn5O5, CaMn4O5 and Ca2Mn3O5 clusters revealed by UB3LYP computations. A bio-inspired strategy for artificial photosynthesis”

Mixed-valence (MV) manganese clusters have been calculated by UB3LYP to elucidate possible roles of substitutions of Mn(II) with Ca(II) in parent manganese oxides; for example hole-doping in Mott insulators for water oxidation. Electron-doping in Mott insulator for reduction reactions is also discussed.