A tetranuclear oxomolybdenum(V) complex with bridging squarate ligands, [MoV4O8(OH)2(H2O)2(C4O4)2]2−

The new tetranuclear polyoxomolybdate(V) ion [MoV4O8(OH)2(H2O)2(C4O4)2]2− has been obtained in one step by the reaction of sodium molybdate, hydrazine and squaric acid in water and crystallized as a potassium salt. The structure has been solved by single-crystal X-ray diffraction showing the location of the hydroxo and water molecule ligands.