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Abstract: A multifunctional ligand of 4,8-disulfonyl-2,6-naphthalenedicarboxylic acid (H4-DSNDA) and its Eu(III) coordination polymer {(H-dpp)[Eu(DSNDA)(H2O)4](H2O)4}n (dpp=1,3-di(4-pyridyl)propane) (1) have been synthesized. Compound 1 is a 2D anionic network based on the paddle-wheel Eu2(CO2)4 building blocks charge-balanced by the monoprotonated H-dpp molecules. Compound 1 shows intense red characteristic europium(III)-centered emission. The Eu(III) emissive state exhibits a single-exponential decay with a lifetime of 0.212ms as measured at 613nm after excitation at 346nm. No observable emission peak arising from the DSNDA4− ligand (λem =408nm) is observed in the emission spectrum of compound 1, indicating an efficient energy transfer occurs from DSNDA4− organic ligand to Eu(III) ions. The results reveal the large π-rich aromatic organic ligand is a suitable chromophoric moiety for sensitization of Eu(III) luminescence. [Copyright &y& Elsevier]

Abstract: Two coordination polymers, namely, [Co(IM)6][Co2(SIP)3] (1) (IM=imidazole, H3SIP=5-sulfoisophthalic acid) and [BMIM]2[Cd2(SIP)3] (2) (BMIM=1-n-butyl-3-methylimidazolium) were synthesized in ionothermal reactions by using ionic liquid 1-n-butyl-3-methylimidazolium tetrafluoroborate as solvent. Single-crystal X-ray analyses revealed that 1 has an anionic 1D polymeric chain charge balanced by an uncommon [Co(IM)6]2+ cation. Complex 2 features an anionic 2D layer containing unique tetranuclear [Cd4(CO2)6(SO3)2] cluster wherein the four Cd atoms are co-planar. The imidazolium cation [BMIM]+ of the ionic liquid acting as charge compensating agent intercalated into the [Cd2(SIP)2]2n− interlayers in structure 2. The rich ionic environments of the ionic liquid may be particularly helpful in the formation of the anionic frameworks of 1 and 2. [Copyright &y& Elsevier]

The title compound, [Zn(C8H4O4)] n, consists of one ZnII cation and one benzene-1,2-dicarboxylate dianion (BDC2−) as the building unit. The ZnII cation is four-coordinated by four carboxylate O atoms from four dianionic BDC2− ligands in a distorted tetrahedral geometry. The ZnII cations are linked by the BDC2− ligands to generate a structure featuring two-dimensional zinc-carboxylate layers containing left- and right-handed helical chains. The two-dimensional layers are stacked along the a direction. The thermal stability of the title compound has been studied. [ABSTRACT FROM AUTHOR]

The reactions of Ln(NO3)3with 2,5-dihydroxy-1,4-benzenedicarboxylic acid (H2-DHBDC) under solvothermal conditions produce a series of isomorphous lanthanide coordination polymers with the empirical formula {[Ln2(DHBDC)3(DMF)4](DMF)2}n(Ln = La(1), Nd(2), Sm(3), Gd(4), and Er(5)). Compound {[Ln2(DHBDC)3(DMF)4](DMF)2}ncontains dinuclear Ln2(COO)6units, which are linked by the –C6H2(OH)2– spacers to form a three-dimensional framework exhibiting α-Po topology (pcu-(412·63) net) based on dinuclear Ln2(COO)6nodes. The three-dimensional framework shows one-dimensional open channels that accommodate the coordinated and guest DMF molecules. Gas adsorption measurements on compound 4indicate that the desolvated solid of 4adsorbs CO2and shows nonporous behavior toward N2. The adsorption favoring CO2over N2may arise from the chemical environments of the host framework, which contains the polar –OH groups of the phenyl and the π-electrons of the ligands. Magnetic measurements on compound 4indicate that there is an antiferromagnetic interaction between Gd3+ions. [ABSTRACT FROM AUTHOR]

Solvo(hydro)thermal reactions of CuX (X = Cl, Br, I) with 4-methyl-1,2,4-triazole-3-thiol (Hmptrz) ligand afforded four new copper(I) coordination polymers, namely, [Cu(μ4-mptrz)]n(1), [Cu(μ2-Hmptrz)(μ2-I)]n(2), [Cu12(μ4-mptrz)4(μ4-I)3(μ3-I)4(μ2-I)]n(3), and [Cu(μ2-Hmptrz)(μ2-DmptrzSS)I]n(4) (DmptrzSS = 4,4′-dimethyl-3,3′-dithiodi-1,2,4-triazole), respectively. Single-crystal X-ray diffraction revealed that compound 1has a two-dimensional (2D) layered structure with (44·62) topology and contains meso-helical (CuS)nchains. Compound 2features a one-dimensional (1D) chain structure constructed from an unusual inorganic [Cu(μ2-S)2Cu(μ2-I)2Cu]nchain formed from two types of four-membered Cu2(μ2-S)2and Cu2(μ2-I)2rings. Compound 3is a two-dimensional (2D) structure constructed from rugby-shaped Cu6I5and planar Cu4I3cluster units, and two types of Cu(mptrz)2units. The I−ion in structure 3displays its coordination versatility with μ4-, μ3-, and μ2- bridging coordination modes. Compound 4has a double-stranded chain structure containing an Hmptrz ligand and DmptrzSS ligand formed from in situ reaction. The structural diversity of these materials is reflected in the variety of coordination polyhedra displayed by the metal sites: linear, trigonal, and tetrahedral. Compounds 1−3exhibit photoluminescences with fluorescent emissions varying from green to red in the solid state. Some structure-related emission shifts compared to the free ligand are studied. The reaction mechanism of the formation of DmptrzSS ligand has been proposed. In addition, elemental analysis, infrared spectra, and thermogravimetric analysis of compounds 1−4are also described. [ABSTRACT FROM AUTHOR]

Two coordination polymers, [Co2(DPSDSDC)(H2O)6]n (1) and {[Cu4(DPSDSDC)2(bpy)4(H2O)2]·11.5(H2O)}n (2) (H4-DPSDSDC =diphenylsulfone-3,3′disulfo-4,4′-dicarboxylic acid and bpy = 4,4'-bipyridine), were prepared and characterized. Compound 1 shows a two-dimensional (2-D) layered structure featuring hydrophilic interlayered spaces and a moderate proton conductivity of 5.22 × 10−5 S cm−1 at 95% RH and 85 °C. Compound 2 contains the linear trinuclear Cu3 units and mononuclear copper(II) units, which are connected by diphenylsulfone-3,3′-disulfo-4,4′-dicarboxylate and 4,4'-bipyridine ligands to afford a 3-D framework. Compound 2 exhibits low proton conductivity resulting from the hydrophobic aromatic rings on the pore walls. [ABSTRACT FROM AUTHOR]

Reactions of cadmium(II) salts with 3-amino-5-methylthio-1H-1,2,4-triazole (Hamstz) afforded two cadmium(II) coordination polymers, [Cd2(amstz)2Cl2]n(1) and [Cd2(amstz)2(NO3)2]n(2). Compounds1and2feature 2-D layered structures based on the dinuclear [Cd2(amstz)2] subunits. The cadmium coordination polyhedra are tetrahedral and tetragonal pyramidal in1and2, respectively, due to the presence of different coordinated anions, Cl−and NO3−. Compounds1and2exhibit photoluminescence emission with maxima at 620 and 621 nm upon excitation at 470 and 472 nm, respectively, which can be attributed to the ligand-to-metal charge transfer emssion. [ABSTRACT FROM AUTHOR]

Hydro(solvo)thermal reactions of cadmium(ii) salts with 4-methyl-1,2,4-triazole-3-thiol (Hmptrz) afforded six novel cadmium(ii) coordination polymers, namely, [Cd(mptrz)2]n(1), [Cd(mptrz)X]n(X = Br (2) and I (3)), [Cd(mptrz)(μ2-X)]n(X = Br (4) and Cl (5)), and [Cd3(μ3-OH)2(mptrz)4]n(6). Compound 1is a 1D looped chain structure. Compounds 2and 3are isostructural and have 1D ladder structures. Compounds 4and 5are isomorphs and feature 2D layered structures. Cadmium(ii) bromide formed 1D ladder of 2and 2D layer of 4, representing an unusual example of Br bond isomerism. Compound 6has a 1D tape structure with an uncommon 1D inorganic Cd2(μ3-OH)2–Cd–Cd2(μ3-OH)2 chain. The structural diversity of these materials is reflected in the variety of coordination polyhedra displayed by the cadmium sites: tetrahedral; trigonal bipyramidal; octahedral. The solid state photoluminescence of all compounds have been investigated. However, only compound 6exhibits photoluminescence with an emission maximum at 435 nm upon excitation at 346 nm. Solid-state density functional theory (DFT) calculations were performed on compound 6. In addition, these compounds were characterized by IR, elemental analysis, and thermogravimetric analysis. [ABSTRACT FROM AUTHOR]