Electrochemical and electrocatalytical investigations on the trimanganese sandwich complex [NaMn3(H2O)2(P2W15O56)2]17−

The trimanganese sandwich complex [ NaMn 3 II ( H 2 O ) 2 ( P 2 W 15 O 56 ) 2 ] 17 - (abbreviated {NaMn3P4W30}) has been characterized by FTIR spectroscopy, 31P NMR spectroscopy and elemental analysis. Despite the close structural similarity of {NaMn3P4W30} with the parent anion αββα-[Mn4(H2O)2(P2W15O56)2]16− (abbreviated {Mn4P4W30}), the two compounds exhibit slightly different electrochemical behaviors. By comparison with {Mn4P4W30}, the MnII centers of {NaMn3P4W30} are more difficult to oxidize while the W centers are more easily reduced. Both complexes present a catalytic effect on nitrite reduction.