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A lanthanide coordination polymer based on H 2 sfdb ligand, namely [Tb 4 (sdbc) 4 (phen) 2 (μ 3 -OH) 4 ] n ∙ 1.5 n H 2 O ( 1 ) (H 2 sfdb = 4,4′-sulfonyldibenzoic acid, phen = 1,10-phenanthroline) has been hydrothermal synthesized and characterized. Compound 1 exhibits an unprecedented three-dimensional framework that comprised new cubane-like hydroxo clusters [Tb 4 (μ 3 -OH) 4 ] 8 + as the nodes and flexible (sfdb) 2 − ligands as the linkers. In 1 , (sfdb) 2 − ligands display completely different four kinds of coordination modes. Interestingly, not only the carboxylate groups but also one oxygen atom of sulfonyl group of (sfdb) 2 − ligand are coordinated with Tb III ions in 1 , which is first found in the compounds based on H 2 sfdb ligand. The luminescence experiments show that Tb III compound exhibits the typical Tb III -centered luminescence. [ABSTRACT FROM AUTHOR]

Abstract: A new cadmium(II) coordination polymer [Cd2(L)2(bpy)]n·nCH3OH (1) (H2L=2-(3-oxo-3-phenylpropionyl)-6-pyridinecarboxylic acid N-oxide, bpy=4,4′-bipyridine), has been synthesized from the reaction of H2L, 4,4′-bipyridine with CdSO4·8/3H2O. Compound 1 is an exceptional non-interpenetrating three-dimensional framework and contains double helical chains and rare cross bpy configuration. Interestingly, these helical chains can span two different directions on other alternate layers. Compound 1 shows intense photoluminescence at room temperature. [Copyright &y& Elsevier]

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 silver(I) coordination polymer, [Ag2(bpdc)]n (1) (H2bpdc = 2,2'-bipyridyl-3,3'-dicarboxylic acid), has been synthesized and characterized. Compound 1 exhibits a 2-D network containing 1-D channels. Each (bpdc)2- is an octadentate μ6-1igand coordinating with six Ag(I)'s in 1. This coordination of (bpdc)2- ligand is first observed here. Neighboring networks are arranged in a [ABAB···] pattern to form 3-D supramolecular architecture by π···π stacking. Compound 1 shows intense photoluminescence at room temperature. [ABSTRACT FROM AUTHOR]

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]