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By systematic change of the solvothermal synthesis, three new coordination polymers, [Cd(L)∙(H2O)]∙2H2O (1), [Cd(L)∙(H2O)]∙H2O (2), and [Cd(L)] (3), have been synthesized based on a tritopic ligand 4-(pyridin-3-yl)isophthalic acid (H2L). Compounds 1 and 2 show very similar two-dimensional (2D) bilayers further linked by interlayer hydrogen bonds into three-dimensional (3D) supramolecular structures, while 3 displays a 3D structure constructed form one-dimensional (1D) Cd-carboxyl chains. Notably, 1 and 2 have a pair of unusual isomers with the opposite orientation of coordinated H2O on the metal centers, leading to different hydrogen bonding interactions. Thermal stabilities and solid-state photoluminescences for 1-3 were also investigated. [ABSTRACT FROM AUTHOR]

A new lead coordination polymer [Pb2(mip)2] (1) has been synthesized under the intervention of polycarboxylic acid by hydrothermal method (H2mip = 5-methylisophthalic acid). X-ray single-crystal structure determination reveals that the polymer crystallizes in monoclinic C2/c space group:a= 21.118(2) Å,b= 8.0055(7) Å,c= 25.556(3) Å, and β = 111.1730(10)°. The Pb(II) cations are connected by four mip anions to produce a 2D (6,3) double-layered framework. It should be noted that four-membered rings by two Pb atoms with twoμ-O atoms of mip groups link each other to form a one-dimensional Pb–O chain through a corner-sharing Pb center. [ABSTRACT FROM PUBLISHER]

Abstract: Six new coordination polymers based on V-shaped linkage 2,5-bis(4-pyridyl)-1,3,4-thiadiazole (bpt) and transition metal ions, [Co(bpt)(pm)0.5(H2O)] n ·3nH2O (1), [Cu2(bpt)(pm)(H2O)4] n (2), [Co(bpt)(pydc)] n ·2nCHCl3 · nH2O (3), [Cu2(bpt)(pydc)2(H2O)2] n (4), [Cu2(bpt)(pydco)2(H2O)2] n · nH2O (5) and [Cd(bpt)(pydco)] n (6) (H4pm=pyromellitic acid, H2pydc=pyridine-2,6-dicarboxylic acid, H2pydco=pyridine-2,6-dicarboxylic acid N-oxide), have been synthesized under the intervention of various polycarboxylate ligands. Complex 1 exhibits a 3-D 4-connected structure with 1-D nanosized open channels encapsulated lots of water molecules. Complex 2 represents a 2-D grid containing two types of rectangular windows. When pydc and pydco instead of pm, complexes 3 and 6 were obtained with highly undulated 2-D layers. The interlayers of 3 are filled with two kinds of solvent molecules, whereas 6 is a double-layered framework without free molecules. Complexes 4 and 5 consist of two distinct 1-D infinite chains held together to form different 2-D supramolecular networks. Importantly, bpt spacer shows changeful conformational geometries and generates complicated crystalline architectures with the introduction of polycarboxylate ligands. Additionally, thermal stability of complexes 1, 3 and 5, fluorescent properties of 6 and X-ray powder diffraction of 1 have also been investigated. [Copyright &y& Elsevier]

Abstract: Via hydrothermal synthesis, the self-assembly of d10 metal, 2,4′-dipyridylamine (L) and 1,3-adamantanediacetic acid (H2ADA) generated two unprecedented coordination polymers [Zn(ADA)(L)] n (1) and [Cd(ADA)(L)2] n (2). Complex 1 possesses a novel 1D looped-chain topology structure decorated with arms. Complex 2 shows an extended threaded framework involving 2D coordination layers of square (44) topology with dangling ligands, which gives the novel (2D→3D) polythreaded array. To the best of our knowledge, complex 2 is the first example with four dangling arms coordinated in the axial sites of dinuclear nodes. In addition, both of the complexes show strong photoluminescence at room temperature, and may be good candidates for potential luminescence materials. [Copyright &y& Elsevier]

Abstract: A novel coordination polymer based on silver(І) and mixed ligands {[Ag2(bpdc)(bpp)(H2O)]·2H2O} n (1) (H2bpdc=2,2′-bipyridyl-4,4′-dicarboxylic acid, bpp=1,3-bis(4-pyridyl)propane), has been prepared by hydrothermal method. Compound 1 has a 2D polymeric structure extended with subunits tetranuclear silver with Schläfli symbol {3^12;4^9;5^6;6^9}{3^18;4^22;5^5}. Compound 1 represents an Ag-containing polymeric compound possessing room-temperature luminescence. [Copyright &y& Elsevier]