Synthesis,Crystal Structure and Theoretical Calculations of a Zinc（II） Coordination Polymer Assembled by Pyrazine-2,3-dicarboxylic Acid and Bis（imidazol） Ligands

A new metal-organic coordination polymer [Zn(pzdc)(mbix)]n·nH2O (H2pzdc = pyrazine-2,3dicarboxylic acid, mbix = 1,3-bis(imidazol-1-ylmethyl)-benzene) 1 has been hydrothermally synthesized and structurally characterized by elemental analysis, IR, TG, fluorescence spectrum and single-crystal X-ray diffraction. Yellow crystals crystallize in monoclinic system, space group P21/n with a = 8.5519(6), b = 14.8764(10), c = 16.4108(11) A, β = 103.4520(10)o, V = 2030.5(2) A, C20H18N6O5Zn, Mr = 487.77, Dc = 1.596 g/cm, F(000) = 1000, Z = 4, μ(MoKα) = 1.257 mm, the final R = 0.0260 and wR = 0.0706 for 3445 observed reflections (I > 2σ(I)). The structure of 1 exhibits a one-dimensional chain-like structure. In addition, natural bond orbital (NBO) analysis was performed by the PBE0/LANL2DZ method in Gaussian 03 Program. The calculation results show obvious covalent interaction between the coordinated atoms and Zn(II) ion.