Synthesis,Crystal Structure and Spectral Property of a Water-bridged Co(Ⅱ) Coordination Polymer with 3-Flavonoxylacetic Acid Ligand

A new cobalt complex with flavonoid carboxylate ligand was synthesized and characterized. X-ray diffraction data revealed that the compound crystallizes in the monoclinic crystal system, space group P2_1/c with a = 7.936(3), b = 21.475(7), c = 20.010(7) ?, β = 102.856(14)o, V = 3325(2) ?~3, Z = 4, C_(34)H_(32)CoO_(15), M_r = 739.53, D_c = 1.477 g/cm~3, F(000) = 1532, μ = 0.591 mm~(-1), R = 0.1123 and w R = 0.1419. In the crystal structure, the Co(Ⅱ) shows 6 coordination geometry, and the flavonoid ligand coordinated with the Co(Ⅱ) ion in a monodentate mode. Hydrogen bonding interactions and π-π stacking interactions lead to the three-dimensional stacking of crystal and increase its stability. Moreover, the thermal stability and luminescent properties of the complex are also investigated. The fluorescence of the complex shows a great reduction of the intensity than that of the ligand.