| Bis-imidazole ligands possess good coordination capability, versatile coordination modes and provide several donor atoms and flexible molecular deformation. The resulting complexes can be widely applicated in catalysis, adsorption, separation and luminescence. Therefore, designing bis-imidazole ligands with different spacer lengths with metal salts could not noly enrich their structural chemistry, but also explore novel functional compounds.In this thesis, we selected a flexible ligand 1,1′-(1,6-hexanediyl) bis-1H-benzimidazole (hbbm) to react with IIB metal salts and got seven 1D, 3D coordination polymers. These complexes were characterized by elemental analysis, IR spectra and single-crystal X-ray diffraction analysis. The contents of this thesis are described as follows:1) The development of coordination polymers containing imidazole ligands were reviewed.2) The reactions of hbbm with IIB metal halide afforded five coordination polymers [ZnCl2(hbbm)]n (1) , [ZnBr2(hbbm)]n (2) , [CdCl2(hbbm)2]n (3) ,[CdI2(hbbm)·0.5H2O]n (4) and [HgI2(hbbm)]n (5). In compounds 1,2,4 and 5, [MX2] cores(1: M = Zn, X = Cl; 2: M = Zn, X = Br; 4: M = Cd,X = I and 5: M = Hg,X = I) and hbbm alternatively constructed to form 1D chain. While in compound 3, the rhombic [Cd4Cl8(hbbm)4] units interconnect through hbbm bridges to form infinitely extended 2D (4,4) net structure. The emission maxima of 1-5 are red-shifted compared to that of hbbm.3) The reactions of hbbm with Cd(OAc)2·2H2O and Zn(OAc)2·H2O produced one [Zn2(μ-OAc)4(hbbm)]n (7)。In compound 6, the trinuclear [Cd(OAc)2]3 fragments are linked by hbbm bridges to form a 1D double chain structure. While in compound 7, 3D structure is obtained via interweaving of U-type chains achieving a 1Dâ†'3D dimensional expansion. The emission maxima of 6-7 are red-shifted compared to that of hbbm. |
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