Assembly of 4-, 6-and 8-connected Cd(II) pseudo-polymorphic coordination polymers: Synthesis, solvent-dependent structural variation and properties

The reaction of Cd(NO3)(2)center dot 4H(2)O, 2,5-thiophenedicarboxylic acid (H(2)tdc) and 1,2-bis(imidazol-1'-yl)methane (bimm) by modulating solvent systems yielded three highly connected pseudo-polymorphic co-ordination polymers based on different dinuclear [Cd-2(CO2)(2)] subunits bridged by carboxylate groups. Single crystal structural analyses reveal structural variation from 4-connected 2D sql layer, 6-connected 2-fold interpenetrated 3D pcu to 8-connected 3D bcu-type network in compounds 1-3. The structural dissimilarity in the structures dependent on the coordination environments of Cd(II) ions and linking modes of mixed ligand influenced by different solvent systems during the synthesis process. Moreover, thermogravimetric and photoluminescence behaviors of 1-3 were also investigated for the first time, and all the complexes emit blue luminescence in the solid state. (C) 2016 Elsevier Inc. All rights reserved.