ZnCl2(4,4′-bpy):: a one-dimensional coordination polymer with two isomorphic phases

Two isomorphic phases of one-dimensional coordination polymer ZnCl2(4,4 ' -bpy) were prepared from hydrothermal reactions of ZnCl2 and 4,4 ' -bipyridyl (4,4 ' -bpy). alpha -ZnCl2(4,4 ' -bpy) (I) crystallizes in the monoclinic space group C2/c, with n=15.821(3) Angstrom, b=5.109(1) Angstrom, c=14.612(3) Angstrom, beta= 110.33(3)degrees. V=1107.5(4) Angstrom (3), Z=4. beta -ZnCl2(4,4 ' -bpy) (II) crystallizes in the orthorhombic space group Pnma, with a=17.349(3) Angstrom, b=12.407(2) Angstrom, c=5.114(1) Angstrom, V=1100.8(3) Angstrom, Z=4. The crystal structures of the two compounds are closely related to each ether. In both phases, the Zn metal center is tetrahedrally coordinated to two terminal Cl and two bridging 4,4 ' -bpy. Each 4,4 ' -bpy acts as a bifunctional ligand and is bonded to two Zn to give rise to a Zn(4,4 ' -bpy) zig-zag chain. The extended Huckel (EH) calculations were performed on both structures to analyze the bonding. The solubility of the title compounds was also tested. (C) 2001 Elsevier Science B.V. All rights reserved.