Hydrothermal syntheses, structures and characterizations of three one-dimensional polyoxomolybdates with 4,4′-dimethylenebiphenyl diphosphonic acid as bridge

Three heterometallic 1-D polymers, [{Ni(1,10-phen)2(H2O)}2 {(Mo5O15)(4,4′-dbp)}·(5.75H2O)] (4,4′-dbp=O3PCH2C6H4C6H4CH2PO3) (1), [{Co(1,10-phen)2(H2O)}2 {(Mo5O15)(4,4′-dbp)}·(5.5H2O)] (2) and [{Ni(2,2′-bpy)3}{Ni(2,2′-bpy)2(H2O)} {(Mo5O15)(4,4′-dbp)}·(4.75H2O)] (3), have been synthesized under hydrothermal conditions. Their structures were determined by single crystal X-ray diffraction. The 1-D chains is constructed of [Mo5O15(4,4′-dbp)]4− units, which are further decorated and charge compensated by [M(1,10-phen)2] (M=Ni, Co) or [Ni(2,2′-bpy)2] subunits. The thermogravimetric analyses and magnetic properties of 1 and 2 were studied.