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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: Two novel Zn(II) coordination polymers, [Zn5(pytpy)8(fum)4(H2O)4(OH)2] n · n(CH3OH)·2n(H2O) (1) and [Zn3(pytpy)4 (btc)2] n ·2n(H2O) (2) (pytpy=4′-(4-pyridyl)-3,2′:6′,3″-terpyridine, H2fum=fumaric acid, H3btc=1,3,5-benzenetricarboxylic acid) have been hydrothermally synthesized and structurally characterized. Complex 1 is a 2D layer structure, which is constructed from linear pentanuclear Zn(II) subunits interconnected via bidentate-bridging pytpy ligands and tridentate-bridging fum2− anions. Complex 2 is a 3D network structure, μ2-pytpy ligands link the layers based on the heart-like hexanuclear subunits to form the 3D network. Both complexes show strong fluorescence emission upon excitation at 310nm in solid state. Additionally, these two complexes possess great thermal stabilities, especially for 2, the framework is stable up to 350°C. [Copyright &y& Elsevier]

A series of Ln-sulfoterephthalate coordiantion polymers, namely, [Ln(2-stp)(4,4'-bbpi) (H2O)2]⋅H2O [Ln = Eu (1), Tb (2), Dy (3)] (2-H3stp = 2-sulfoterephthalate; 4,4'-bbpi = 4,4'-bisbiphenylimidazole), were prepared by hydrothermal method and characterizatied by EA, IR, TGA, and PXRD technologies. Single crystal X-ray diffraction analyses show that the three complexes are isostructral twodimensional network featuring helical chain structures. The fluorescence studies show that the emissions of the coordination polymers exhibit the characteristic peaks of lanthanide ions, which means they could be potential fluorescence materials. [ABSTRACT FROM AUTHOR]