Manganese-manganese separations in oxide- and alkoxide-bridged complexes: correlation of structure with ligand type and number

The Mn(IV) oxide dimer of 1,3-bis(salicylideneamino)propane and the Mn(III) chloride dimer of methanolic 1-(salicylideneamino)-3-hydroxypropane complement 20 other oxide- and alkoxide-bridged manganese complex dimers in a correlation study between Mn-Mn separation and the Mn-O-Mn bridge angle. The study shows that mu-oxo bridges follow the law of cosine correlation while single-atom mu-alkoxo bridges do not. Despite deviations, the study manages to set an empirical correlation slope of 0.03 angstroms/degree within the 2.86-3.81 angstrom range. The implications of these findings in the behavior of multinuclear manganese enzymes are discussed.