A New 2D Zinc(II) Coordination Polymer Constructed by Imidazole-4,5-dicarboxylic Acid(H_3IDC) and 1,4-Bis(imidazol-1-ylmethyl)-benzene(bix)

A new 2D Zn(Ⅱ) coordination polymer [Zn(HIDC)(bix)0.5]n(1) was obtained by the hydrothermal reaction of ZnCl2,imidazole-4,5-dicarboxylic acid(H3IDC) and 1,4-bis(imidazol-1-ylmethyl)-benzene(bix) with a 2:2:1 mole ratio.X-ray diffraction crystal structural analysis reveals it crystallizes in monoclinic,space group P21/n with a = 12.125(3),b = 10.541(3),c = 12.484(3) ,β = 115.834(4)°,V = 1436.0(6) 3,Mr = 338.60,Z = 4,Dc = 1.566 Mg·m-3,F(000) = 684,μ(MoKα) = 1.730 mm-1,the final R = 0.0439 and wR = 0.0888 for 2101 observed reflections with I ≥ 2σ(I).In 1,each zinc(Ⅱ) ion is five-coordinated with a slightly distorted trigonal bipy-ramidal coordination geometry,and each μ2-HIDC2-acts as a bridge to bond two neighboring Zn(Ⅱ) ions,leading to a 1D zigzag chain architecture.The adjacent zigzag chains are further linked by μ2-bix to form an infinite 2D network structure.The fluorescence spectrum of 1 exhibits intense emission at 466 nm when excited at 397 nm in solid state at room temperature.