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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: Compound {(EMIM)2[Zn7(μ4-O)2(1,4-ndc)6]}n (1) (EMIM=1-ethyl-3-methylimidazolium and 1,4-ndc=1,4-naphthalenedicarboxylate) has been synthesized by using the mixed ionic liquids of 1-ethyl-3-methylimidazolium tetrafluoroborate and 1-ethyl-3-methylimidazolium l-lactate as solvent. Compound 1 has a 3D anionic framework with bcu-(424·64) topology based on a unique heptanuclear [Zn7(μ4-O)(μ2-COO)10] cluster as secondary building unit. The imidazolium cation [EMIM]+ of the ionic liquid acting as extra framework charge-balancing species occupies the channels of the 3D anionic framework. The roles of the ionic liquid in ionothermal synthesis and crystallization of compound 1 are briefly discussed. The thermal and photoluminescent properties of compound 1 have also been investigated. [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]

A 3D coordination polymer [CdK 6 (μ 2 -H 2 O) 2 (BODSDC) 2 (H 2 O)] n ( 1 ) based on the novel benzophenone-3,3′-disulfonyl-4,4′-dicarboxylate (BODSDC 4− ) ligand was synthesized and structurally characterized. The carboxylate and sulfonate groups of the organic ligands as well as the bridging water molecules connect the Cd 2+ and K + ions to produce a 2D layer, which is linked by the benzophenone moieties to give a 3D pillared framework. Compound 1 crystallizes in an acentric space group of Cc and has a large second-harmonic-generation (SHG) response of 1.3 times that of potassium dihydrogen phosphate (KDP) in the particle size of 25–210 μm. Further SHG measurements revealed that the material is type-I phase-matchable. The observed SHG efficiency is associated with the unsymmetrical geometry of the organic ligand and the distorted coordination polyhedrons of metal centers. [ABSTRACT FROM AUTHOR]

2-Fold interpenetrating chiral quartz nets with opposite handedness have been observed in a centrosymmetric coordination polymer {[Zn3(bmzbc)6]·11.5DMF}n (Hbmzbc = 4-(benzimidazole-1-yl)benzoic acid), which is a unique example of an interpenetrating enantiomorphic pair of quartz nets that have never been realized before. [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 isomorphous compounds [Eu(2,2′-bpdc)(NO3)(e-urea)3]n (1) and [Tb(2,2′-bpdc)(NO3)(e-urea)3]n (2) (2,2′-bpdc2−=2,2′-biphenyldicarboxylate and e-urea=ethyleneurea) have been synthesized using a deep-eutectic solvent of choline chloride/e-urea. The lanthanide ions are linked by the 2,2′-bpdc2− ligands to form one-dimensional helical chains in these compounds. Of special interest is the presence of parallel left- and right-handed single helices with the ratio of 1:1 in both compounds. Detailed photoluminescence studies show that both compounds exhibit typical lanthanide luminescent emissions and the excitation energy has been efficiently transferred to the lanthanide ions from the organic ligands. [ABSTRACT FROM AUTHOR]

Three cadmium(II) coordination polymers constructed from 5,7-disulfonate-1,4-naphthalenedicarboxylate and N-containing ligands, {[Cd2(DSNPDC)(phen)(H2O)4]·2.5H2O}n (1), {[Cd2(DSNPDC)(phen)2(H2O)4]·3H2O}n (2) and [Cd2(DSNPDC)(bpy)2(H2O)4]n (3) (H4-DSNPDC = 5,7-disulfonate-1,4-naphthalenedicarboxylic acid, phen = 1,10-phenanthroline, and bpy = 2,2′-bipyridine), were synthesized and characterized. Compound 1 displays a two-dimensional (2D) layered structure. In 2 and 3, the dinuclear [Cd2(COO)2] units are connected by DSNPDC4– ligands to generate one-dimensional (1D) chains. Due to the presence of the terminal chelating phen/bpy ligands, all compounds show low dimensional structures. Compounds 1–3 exhibit fluorescence emissions centered at 378, 419 and 376 nm, respectively, which are assigned to ligand-centered emissions or ligand-to-metal charge transfer. [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]

A three-dimensional structure [Zn(H-ntb)] n (1) constructed from the tetrahedrally coordinated Zn(II) atoms and 4,4′,4′'-nitrilotribenzoate ligands was presented. Compound 1 exhibits a phase-matchable second-harmonic-generation response of 1.2 times that of KDP. • A noncentrosymmetric coordination network. • A compound constructed from the 4,4′,4′'-nitrilotribenzoate. • Helical chains based on the 4,4′,4′'-nitrilotribenzoate and [ZnO 4 ] tetrahedrons. • A 3D zinc compound exhibits a large SHG response. A coordination polymer [Zn(H-ntb)] n (1) based on the tritopic carboxylate linker of 4,4′,4′'-nitrilotribenzoate (H 3 -ntb) was reported here. Compound 1 crystallizes in a polar space group of Pca 2 1 and contains two-dimensional layers formed from the left- and right-handed helical chains pillared by the benzoate moieties to give a three-dimensional structure. The present compound 1 features a noncentrosymmetric structure and displays a strong phase-matchable second-harmonic-generation (SHG) response of 1.2 times that of potassium dihydrogen phosphate (KDP). The inherent polarity of the 4,4′,4′'-nitrilotribenzoate and distortive [ZnO 4 ] tetrahedrons as well as the asymmetric arrangement of the building blocks are responsible for the SHG activity for 1. [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]

Two cadmium(II) coordination polymers, namely, [Cd3( m-phth)2(atz)2] n ( 1) ( m-phth = m-phthalate and atz = 3-amino-1,2,4-triazolate) and [Cd(atphth)(H2O)] n ( 2) (atphth = 2-aminoterephthalate), were synthesized and structurally characterized. Compound 1 features a three-dimensional (3D) pillared framework based on two-dimensional (2D) cadmium-benzenedicarboxylate ladders pillared by the triazolate ligands. Compound 2 has a 3D framework constructed from 2D cadmium-benzenedicarboxylate layers, which are further linked by Cd-N bonds between the cadmium ions and amino groups of the atphth2- ligands of the adjacent layers to form the final 3D structure. Compounds 1 and 2 exhibit solid-state photoluminescence with emission maxima at 448 and 470 nm, respectively. [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]