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A new metal-organic framework, {[Co1.5(μ2-OH)(L)(bipy)0.5] ·0.5DMF}n (1) (H2L = (4,4'-(hexafluoroisopropylidene)bis(benzoic acid) and bipy = 4,4'-bipyridine), has been prepared under solvothermal conditions using flexible dicarboxylate and rigid N-donor co-ligands in the presence of Co(II) ion as the building blocks. The x-ray single-crystal diffraction analysis indicates that 1 possesses a three-dimensional (3D) layer-pillar structure with one-dimensional (1D) metal-carboxylate chain. The Co(II) ions are bridged by L2- to generate a two-dimensional (2D) sheet, which is further pillared by bipy into a 3D framework with {44.62}{45.65}2 topology. In addition, the variable-temperature magnetic susceptibility measurement indicates there exists an anti-ferromagnetic behavior between in the Co(II) ions of 1. [ABSTRACT FROM AUTHOR]

Using a triazole carboxylic ligand (H2L = 4-(1H-1,2,4-triazol-1-yl) isophthalic acid), four water-stable lanthanide metal-organic frameworks (Ln(III)-MOFs) (1-Ln, Ln(III) = Tb, Eu, Dy, and Sm), [Ln(L)(HL)(H2O)2], where the deprotonated H2L ligands have two different coordination modes: L2− and HL− [(a): η2μ2χ2, η2μ1χ2; (b): η2μ1χ2], have been synthesized by solvothermal reaction and characterized by elemental analysis, FT-IR spectroscopy, powder X-ray diffraction (PXRD), and thermogravimetric analysis (TGA). Single-crystal X-ray diffraction analyses show that Ln(III)-MOFs are isostructural with 2D-layered structures with uncoordinated carboxylic and triazole groups. The luminescent properties of 1-Tb in aqueous solution containing different cationic solutions and small organic solvents have been explored under ultraviolet irradiation at room temperature. The high quenching constant KSV values and low detection limits indicate that 1-Tb exhibits extremely high detection sensitivity and selectivity toward Fe3+ ions and nitrobenzene; 1-Tb can keep its original network and be reused after the sensing experiments, which provide us with an optical material for detecting Fe3+ ions and nitrobenzene. Magnetic studies show that antiferromagnetic exchange interactions exist between Dy(III) ions in 1-Dy. [ABSTRACT FROM AUTHOR]

A new zinc(II) coordination polymer, namely [Zn(bipy)2(H2O)4]n·n(dsba) (1), has been synthesized by the mixed 4,4'-biphenyldisulfonic acid (H2dsba) and 4,4'-bipyridine (bipy) ligands with Zinc(II) salt under the common solution evaporation method. The results of the X-ray crystal diffraction analysis show that complex 1 belongs to the monoclinic system with P21/c space group. The unit cell constants of complex 1 are a = 9.2579 Å, b = 12.2016 Å, c = 14.447 Å, α = γ = 90°, β = 93.476°. Complex 1 exhibits a three-dimensional supramolecular network based on the discrete structure by utilizing various H-bonded interactions. In addition, the properties of complex 1, such as the elemental analysis, FT-IR spectroscopy, X-ray powder diffraction, and fluorescence spectroscopy were also characterized and are discussed in detailed. [ABSTRACT FROM AUTHOR]

A coordination polymer, [Pb2(OH)(tzia)]·2H2O (1), has been prepared by solvothermal reaction of 5-(1H-tetrazol-5-yl)isophthalic acid (H3tzia) and Pb(NO3)2. The polymer1is based on an unprecedented centrosymmetric tetranuclear [Pb4(OH)2(COO)4(ttaz)2] cluster linked by a multidentate tzia ligand, affording a 2-D 3,6-connectedkgdlayer. The adjacent layers are further jointed by Pb⋯O interactions to form a 3-D supramolecular framework with a rare (3,8)-connectedtfz-d; UO3topology. Photoluminescent properties of H3tzia,1, and1-desolvated have been further investigated, and it was interesting to find that1-desolvated due to the removal of lattice water molecules reveals stronger photoluminescence than1. [ABSTRACT FROM PUBLISHER]

Three new complexes, {[Mn(dtb)(bpe)·2H2O]·H2O}n(1), {[Mn(dtb)(bpa)·2H2O]·H2O}n(2), and {[Mn(dtb)(phen)]}n(3) [H2dtb = 5,5′-dithiobis(2-nitrobenzoic acid), bpe = 1,2-bis(4-pyridyl)ethene, bpa = 1,2-bi(4-pyridyl)ethane, phen = 1,10-phenanthroline], have been synthesized under hydrothermal conditions with Mn(OAc)2·4H2O, dtb, and differentN-donor ligands. X-ray structure analyses of1and2reveal analogous structures with 1D helical chains and 2D 44chiral layers. The structure of3shows a 1D chain which is outwardly decorated with phen ligands. These neutral polymeric complexes exhibit structural diversity due to the different coordination modes of the flexible dtb ligand and the N-donor ligands. The thermogravimetric analyses and X-ray powder diffractions of1–3are also presented. [ABSTRACT FROM AUTHOR]

A novel dysprosium(III) complex with N-(2-propionic acid)-salicyloyl hydrazone (C10H10N2O4, H3L) and 2,2-dipyridyl (C10H8N2, dipy) was prepared and characterized. The crystal structure of [Dy(H2L)(HL)(H2O)3]·0.5dipy·2H2O was determined by X-ray single crystal diffractometry. The crystal complex crystallizes in the triclinic system with space group . In the structure, Dy(III) is 9-coordinated by carboxyl O and acyl O atoms and azomethine N atoms of two ligands (H2L and HL forms) and O atom from three water molecules. H2L and HL act as tridentate ligands which form two stable five-numbered rings shared one side with keto-mode as indicated by the result of the crystal structure and infrared spectral analysis. The coordination polyhedron around Dy(III) was described as a monocapped square antiprism. One free 2,2-dipyridyl and two lattice waters connecting with coordinated water and ligands by hydrogen bonds lie in the crystal cell. The complex formed a three-dimensional super molecule in space through hydrogen bonds. The complex exhibits good fluorescence property. [ABSTRACT FROM AUTHOR]