A New 2D Zinc(II) Coordination Polymer Constructed by Imidazole-4,5-dicarboxylic Acid (H3IDC) and 1,4-Bis(imidazol-1-ylmethyl)-benzene (bix)

A new 2D Zn(II) coordination polymer [Zn(HIDC)(bix)(0.5)] (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 P2(1)/n with a = 12.125(3), b = 10.541(3), c = 12.484(3) angstrom, beta = 115.834(4)degrees, V = 1436.0(6) angstrom(3), M-r = 338.60, Z = 4, D-c = 1.566 Mg.m(-3), F(000) = 684, mu(MoK alpha) = 1.730 mm(-1), the final R = 0.0439 and wR = 0.0888 for 2101 observed reflections with I >= 2 sigma(I). In 1, each zinc (II) ion is five-coordinated with a slightly distorted trigonal bipyramidal coordination geometry, and each mu(2)-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 mu(2)-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.