Synthesis of Centered Icosahedral Europium Cluster Formed by Bis(L-prolinato)nickel(II) Ligands and Isolation of an Electrochemically Reduced Product of Its Cluster

A centered icosahedral europium(III) cluster formed by bis(L-prolinato)nickel(II) ligands was prepared and an electrochemically reduced product of its cluster was isolated. The crystal of the reduced product was isomorphous to that of the EuIII-cluster and the cluster structure was retained in the reduced product.