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Two new coordination polymers with an asymmetric dicarboxylate and 4,4?-bipyridine ligand, {[Co(bpy)(H2O)4]·(cpa)·0.5H2O}n(1) and {[Ag(cpa)(bpy)][Ag(bpy)]·4H2O}n(2) (H2cpa = 4-(2-carboxyethyl)benzoic acid, bpy = 4,4?-bipyridine), have been hydrothermally synthesized and characterized by elemental analysis, FT-IR spectroscopy, and single-crystal X-ray diffraction. Compound1displays a linear chain with guest molecule (cpa)2?ions existing in the structure. Compound2contains two independent units, [Ag(cpa)(bpy)]–(A) and [Ag(bpy)]+(B), which form a 1-D + 1-D structure.Ashows a 1-D chain structure bearing hooks formed by the carboxylates and organized into a tubular structure by hydrogen-bonding interactions.Bhas linear chains formed from Ag+and bpy. TheAandBchains co-crystallize with waters of crystallization to provide two linear [Ag(bpy)]+chains embedded in the tubular structure formed byAvia?…?stacking contacts. In1and2, hydrogen-bonding and?…?stacking interactions connect the discrete 1-D chains into 3-D supramolecular structures. The fluorescent properties, TG analysis, and X-ray powder diffraction patterns for1and2were also measured. [ABSTRACT FROM PUBLISHER]

Abstract: Four new mixed-ligand complexes, namely [Zn2(pam)2(2,2′-bpy)2] (1), [Cd(pam)(2,2′-bpy)2] n (2), [Zn(pam)(phen)] n (3) and [Cd (pam)(phen)] n ·0.5n CH3CH2OH·0.5nH2O (4) (H2pam=pamoic acid, 2,2′-bpy=2,2′-bipyridine, phen=1,10-phenanthroline) have been synthesized under hydro(solvo)thermal conditions. Complex 1 possesses a discrete dinuclear metallamacrocyclic structure. Complex 2 is a 1D homochiral helical coordination polymer that is built from achiral components, whereas 3 displays a 1D helical chain structure. 4 is an unusual 2D double-layered structure generated by π⋯π interactions of two 2D networks. The structural differences of these complexes are mainly due to the differences of the size of the rigid aromatic chelate ligands and d10 metal ions. It appears that the chelate ligands and metal ions of the larger size favor the formation of high-dimensional structures, whereas those of the smaller size favor the formation of low-dimensional structures in the present system. The photoluminescence and thermal stability of these complexes were investigated. [Copyright &y& Elsevier]