A unique manganese (II) 2D polymer containing 2, 5-di(2',4'-dicarboxylphenyl) pyridine and oxalate mixed ligands: Structure and magnetic property

摘要

Solvothermal reaction of conjugated pyridine/benzene dicarboxylic acid ligand with manganese acetate in the presence of ammonium oxalate afforded a novel 2D polymer, {[Mn4(ddpp)2 (μ4-C2O4)·6H2O]·2H2O}_n (ddpp = 2, 5-di(2',4'-dicarboxylphenyl) pyridine) (1). It has been characterized by element analysis, thermogravimetry, infrared spectroscopy and single-crystal X-ray diffraction studies. Polymer 1 is constructed from tetranuclear Mn~(II) clusters through oxalate bridging, in which four adjacent Mn~(II) ions are linked into a parallelogram-core aggregate, and the polymer 1 exhibits 1D double-zigzag chains bearing a ladder-like topology feature. The ddpp ligands further interconnect these 1D double chains into 2D corrugated-shape network. Variable temperature magnetic susceptibility measurements indicate that polymer 1 exhibits weak antiferromagnet-ic interactions.