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Two novel d10 metal coordination polymers [Cd2(Hmna)4] n ( 1), [Zn2(ddca)2 (dpe)] n ·nH2O ( 2) (H2mna = 6-mercaptonicotinic acid, H2ddca = 6, 6'-dithiodinicotinic acid, dpe = 1, 2-bis(4-pyridyl)ethylene), were hydrothermally synthesized and characterized by single-crystal X-ray diffraction. Compound 1 is a cyclic double chain structure containing 16-number and 32-number circles with (Hmna)- ligands as bridges, in which the starting H2ddca reagent was unprecedentedly converted into H2mna ligands via in situ cleavage of S-S bonds during the course of hydrothermal treatment. In compound 2, two five-coordinate zinc centers are connected with carboxylate groups of H2ddca ligands to give a binuclear [Zn2(CO2)4] unit, which are linked by dpe ligands to form a 2D network structure. It is worth noting that compound 2 displays a twofold 2D+2D parallel interpenetration framework containing a polyrotaxane-like motif. In addition, the thermal stablities and photoluminescence properties of compounds 1 and 2 were also studied. [ABSTRACT FROM AUTHOR]

Abstract: Three novel d10 metal coordination polymers, {[Cd(H2odpa)(phen)2]·H2O} n (1), [Cd2(odpa)(phen)(H2O)2] n (2), {[Zn4(odpa)2(phen)2(H2O)2]·H2O} n (3), (H4odpa=4,4′-oxydiphthalic acid, phen=1,10-phenanthroline) were obtained with different metal/ligand ratios through hydrothermal method and characterized. Compound 1 forms a one dimensional zigzag chain, in which two phen ligands chelate to one cadmium atom. Compound 2 shows a three dimensional network structure comprised of new tetranuclear cadmium clusters as the nodes and (odpa)4− anions as the linkers, exhibits an unusual topological structure. Compound 3 is an unprecedented three dimensional polymer based on octanuclear zinc clusters cross-linked by (odpa)4− anions. In 1–3, central CdII/ZnII ions and (odpa)4− ligand display completely different coordination modes and conformations. In addition, the thermal stabilities and photoluminescence properties of 1–3 were also studied. [Copyright &y& Elsevier]

Abstract: Two novel cadmium(II) coordination polymers [Cd(pyip)(ox)]·H2O (1) and [Cd2(pyip)2(ox)2·(H2O)][Cd(pyip)(ox)]·4(H2O) (2) (pyip=2-(pyridin-3-yl-1H-imidazo [4,5-f][1,10]phenanthroline, H2ox=oxalic acid), have been hydrothermal synthesized and characterized by single crystal X-ray diffraction. Compound 1 is 1D zigzag chain, in which oxalate anion as bridging ligand is responsible for the formation of the main framework and pyip as chelating ligand grafts on two sides of the zigzag chain. Compound 2 contains two kinds of independent polymers [Cd2(pyip)2(ox)2(H2O)] (A) and [Cd(pyip)(ox)] (B) to form an interdigitated 1D+1D structure, in which polymers A and B are paratactically assembled in an ABCD sequence. The fundamental unit of polymer B in 2 is the same as that in 1. For compounds 1–2, weak interactions, primarily hydrogen bonding and π⋯π stacking interactions, have greatly influence on the supramolecular motifs recognized in the crystal packing. Especially, the oxalate anions as bridging ligand simultaneously adopt multiform coordination modes in two compounds. In addition, 1 and 2 displayed a strong fluorescent emission in the solid state at room temperature. [Copyright &y& Elsevier]

Abstract: To determine the influence of metal ion and the auxiliary ligand on the formation of metal–organic frameworks, six new coordination polymers, {[Mn2(bpdc)(bpy)3(H2O)2]·2ClO4 ·H2O} n (1), {[Mn(bpdc)(dpe)]·CH3OH·2H2O} n (2), {[Cu(bpdc)(H2O)2]} n (3), {[Zn(bpdc)(H2O)2]} n (4), {[Cd(bpdc)(H2O)3]·2H2O} n (5), and {[Co(bpdc)(H2O)3]·0.5dpe·H2O} n (6) (H2bpdc=2,2′-bipyridine-3,3′-dicarboxylic acid, bpy=2,2′-bipyridine, dpe=1,2-di(4-pyridyl) ethylene), have been synthesized and characterized. Compound 1 forms 1D helical chain structure containing two unique MnII ions. In 2, the bridging ligand dpe links Mn-bpdc double zigzag chains to generate a layer possesses rectangular cavities. In 3, bpdc2− ligand connects to three metal centers forming a 2D network. Different from the above compounds, 4 displays a 1D double-wavelike chain. Compound 5 features a helical chain. Compound 6 also displays a helical chain with guest molecule dpe existing in the structure. These diverse structures illustrate rational adjustment of metal ions and the second ligand is a good method for the further design of helical compounds with novel structures and properties. In addition, the magnetic properties of 2, 3 and 6, the thermal stabilities and photoluminescence properties of 4 and 5 were also studied. [Copyright &y& Elsevier]

Abstract: A novel Ag(I) compound [Ag(H2cpop)(bpy)] n (1) (H3cpop=4-(4-carboxyphenoxy) phthalic acid, bpy=4,4′-bipyridine), has been hydrothermally synthesized and structurally characterized. H3cpop came from the in situ decarboxylation of H4odp (H4odp=4,4′-oxydiphthalic acid) in the hydrothermal reactions. Compound 1 was obtained from the self-assembly of Ag(I) salt with bpy and H4odp ligands to form a 1D chain bearing hooks with carboxyl groups. The two chains are recognized each other to generate molecular zipper structure by hydrogen bonding interaction between the bearing carboxyl groups. Compound 1 is stable in air, and show intense photoluminescence at room temperature. [Copyright &y& Elsevier]

One new heterometallic complex [Cd 2 Cu(BTC) 2 (H 2 O) 2 ]⋅2H 2 O ( 1 ) (BTC = benzene-1,3,5-tricarboxylate), has been synthesized and characterized by elemental analysis and single-crystal X-ray diffraction techniques. The structure indicates that the complex 1 crystallizes in triclinic, space group P ī, in which, the carboxylate groups of BTC ligand adopt μ 2 –η 1 :η 1 , and μ 2 –η 2 :η 1 coordination modes, bridging Cd(II) and Cu(II) atoms to generate 2D Cd-BTC bilayer then to a (4,6)-connected open 3D framework with 1D channels occupied by guest water molecules. In addition, thermal gravimetric analysis (TGA) and luminescent property of 1 were investigated. [ABSTRACT FROM AUTHOR]