A Novel Three-dimensional Ni Coordination Polymer Based on Flexible Di-carboxylate Ligand and 4,4-Pyridine： Synthesis, Characterization and Topological Analysis

A novel Ni(II) coordination polymer Ni(dtba)(4,4′-bpy)] (1, H2dtba = 2,2′-dithio- bisbenzoic acid, 4,4′-bpy = 4,4′-bipyridine) has been synthesized by H2dtba and Ni(CH3COO)2·4H2O with exo-bidentate rigid ligand 4,4′-bpy by using hydrothermal method, and its structure was determined by single-crystal X-ray diffraction. X-ray crystal structure analysis reveals that complex 1 crystallizes in monoclinic, space group Cc with a = 11.7624(9), b = 18.7933(19), c = 10.3071(11), β = 97.6510(10)°, V = 2258.2(4)3, Z = 4, C24H16N2NiO4S2, Mr = 519.22, Dc = 1.527 g/cm3, μ = 1.079 mm-1 and F(000) = 1064. The structure was solved by direct methods and refined to R = 0.0434 and wR = 0.1000 for 3281 observed reflections (I > 2σ(I)). The coordination environment of Ni(II) is a distorted octahedron, and a three-dimensional structure was formed with the coordination effect of dtba2- and 4,4′-bpy ligands. The topological analysis reveals that the whole framework of 1 is a 2-nodal net of (52.6)(53.64.72.8) topology. The thermal stability and XRD pattern of 1 were also investigated.