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Two new coordination polymers [Cd(bmb)(hmph)]n (1), {[Ag(bmb)]·H2btc}n (2) (bmb=1,4-bis(2-methylbenzimidazol-1-ylmethyl)benzene, H2hmph=homophthalic acid, H3btc=1,3,5-benzenetetracarboxylic acid) were synthesized under hydrothermal conditions and characterized by single-crystal X-ray diffraction methods, IR spectroscopy, TGA, XRPD and elemental analysis. Complex 1 features a 3D threefold interpenetrating dia array with a 4-connected 6(6) topology. Complex 2 shows a 1D helix chain structure connected by L1 ligands, which is finally extended into a rarely 2D 4L2 supramolecular network via C-H⋯O hydrogen bond interactions. In addition, the luminescence and catalytic properties of the two complexes for the degradation of the methyl orange azo dye in a Fenton-like process were presented. The degradation efficiency of the methyl orange azo dye for 1 and 2 are 56% and 96%, respectively., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Three novel metal–organic frameworks, formulated as [Co(HDCPN)(4,4′-bibp)]·1.5H2O (1), [Cd3(DCPN)2(4,4′-bibp)2H2O]·1.5H2O (2) and [Mn3(DCPN)2(4,4′-bibp)3(H2O)4] (3) (H3DCPN = 6-(3,5-dicarboxylphenyl)nicotinic acid and 4,4′-bibp = 4,4′-bis(imidazolyl)biphenyl), have been solvothermally synthesized based on an unsymmetrical rigid carboxylate ligand. Single-crystal X-ray diffraction analysis shows that complex 1 is an sql/Shubnikov tetragonal plane network with mononuclear Co(ii) ions, which is connected by O2…H2…O1 hydrogen bonds to generate a 3D framework. Complex 2 is a new 3D (3,10)-c network based on trinuclear Cd clusters. Complex 3 is an extended 3D (3,10)-c network based on trinuclear Mn clusters, which belongs to 3,10T3 (MOF.ttd). Complex 2 exhibits potential application for the luminescence sensing of nitrobenzene derivatives. Furthermore, the variable-temperature magnetic susceptibilities of complexes 1 and 3 indicate that they exhibit antiferromagnetic behavior and ferromagnetic behavior between metal ions, respectively. [ABSTRACT FROM AUTHOR]

One chiral Cu(I) metal–organic framework {[Cu(DCI)]·0.1Cyc·0.45Nbenz} n ( 1 ) (HDCI = 4,5-dicyanoimidazole, Cyc = cyclohexanol, Nbenz = nitrobenzene), was obtained under solvothermal condition. Complex 1 presents a 3D chiral porous framework with 38.2% porosity. The 3D metal–organic framework can be regarded as a PtS net with the vertex symbol of {4 2 .8 4 }. The gas adsorption/desorption experiments of complex 1 have been measured at 77 K. Moreover, the CD spectrum and photoluminescent behavior of complex 1 have been studied. [ABSTRACT FROM AUTHOR]

Under hydrothermal conditions, three new AgI coordination polymers, [Ag(L1)(Hmip)] n ( 1), [Ag(L2)0.5(ndc)0.5] n ( 2), and {[Ag(L3)0.5(Htbi)] ·0.25H2O} n ( 3) [H2mip = 5-methylisophthalic acid, L1 = 1,4-bis(2-methylbenzimidazol-1-ylmethyl)benzene, H2ndc = 2,6-naphthalenedicarboxylic acid, L2 = 1,3-bis(2-methylbenzimidazol-1-ylmethyl)benzene, H2tbi = 5- tert-butyl isophthalic acid, L3 = 1,4-bis(5,6-dimethylbenzimidazole)butane] were synthesized by employing flexible bis(benzimidazole) and dicarboxylic acid ligands. Polymer 1 displays a 2D 4-connected 4L2 underlying net topology with the point symbol of (65.8) in standard representation. Compound 2 possesses a 2D uninodal 4-connected Shubnikov tetragonal plane net (sql) based on a dinuclear AgI clusters with the point symbol (44.62), which is further extended into a 3D supramolecular framework by π-π interactions. Compound 3 possesses dinuclear molecular complex groups, which form chains by weak Ag-O (2.6 Å) coordination bonds, and further assembled into a 2D supramolecular layer by hydrogen bonds and π-π stacking interactions. These complexes exhibit intense fluorescent emissions in solid state. UV/Vis diffuse reflection spectra and the excellent catalytic activity for the degradation of the congo red azo dye in a Fenton-like process are discussed. [ABSTRACT FROM AUTHOR]

Abstract: Gd2−x−y Eu x Sm y (MoO4)3 (x =0, 0.20, 0.40, 0.60, 0.80, 1.0, 1.2, 1.4, 1.6, 1.8, 2.0, and y =0, 0.020, 0.024, 0.028, 0.032, 0.036, 0.040) were prepared by solid-state reaction technique at 800°C and 950°C respectively; two types of host structure (monoclinic structure for 800°C and orthorhombic structure for 950°C) were obtained. The photo-luminescent results show that Gd0.372Eu1.6Sm0.028(MoO4)3 with orthorhombic structure exhibits the most intense red-emitting under near UV excitation. In the Eu3+–Sm3+ co-doped system, both Eu3+ and Sm3+ f–f transition absorptions are observed in the excitation spectra, the intensities of the main emission line (5D0 → 7F2 transition of Eu3+ at 615nm) are strengthened because of the energy transition from Sm3+ to Eu3+. With the broadened absorption around 400nm, strengthened emission intensity at 615nm and the appropriate chromaticity coordinates (x =0.65, y =0.33), the phosphor Gd0.372Eu1.6Sm0.028(MoO4)3 was combined with a ∼400nm emitting InGaN chip to obtain an intense red-emitting LED finally. [Copyright &y& Elsevier]

Abstract: A series of Eu3+-doped solid solution of tungstate and molybdate were prepared by solid-state reaction technique and their photoluminescence property were investigated for searching a new red phosphor for UV InGaN-based light-emitting diode (LED). The phosphors show intensely red emission with good color purity. Among these phosphors, GdEu(MoO4)0.5(WO4)2.5 exhibits the strongest red emission under 395nm light excitation and appropriate CIE chromaticity coordinates (x =0.67, y =0.33) same with the NTSC standard values, and with which a red UV InGaN-based LED was fabricated based on the standard LED technology at I F =20mA. The emission spectrum of the red LED indicates that this red phosphor is a potential candidate for the near UV InGaN based LEDs. [Copyright &y& Elsevier]

Two new copper( II) complexes with the formulas [Cu(btb)(pydc)( H2O)] n ( 1) and [Cu(btb)0.5(nph)( H2O)] n ( 2) have been synthesized under hydrothermal conditions by employing a rigid bis(triazole) ligand (btb = 4,4′-bis(1,2,4-triazolyl-1-yl)-biphenyl) and two carboxylic acids mixed ligands (H2pydc = pyridine-2,5-dicarboxylic acid and H2nph = 3-nitrophthalic acid). The copper atoms present different environments, with a tetragonal pyramidal geometry in 1 and octahedral configuration in 2. Complex 1 displays a dinuclear cluster, which is further packed into a 2D supramolecular layer by classical OH · · · O hydrogen bonds. Complex 2 possesses a trinodal 3,4,4-connected 3D framework with a rare sqc69 topology. In addition, thermal stability and luminescence property were investigated. [ABSTRACT FROM AUTHOR]

Two new coordination polymers, namely, {[Cu 3 (BCPB)(HBCPB)(H 2 BCPB)(H 2 O)]·(CH 3 OH)(H 2 O)} n ( 1 ), and {[Cd(HBCPB)(1,4-bib) 1.5 ]·4H 2 O} n ( 2 ) (H 3 BCPB = 3,5-bis(2-carboxy-phenoxy)-benzoic acid, 1,4-bib = 1,4-bis(1H-imidazol-4-yl)benzene), have been synthesized under hydrothermal conditions and characterized by single-crystal X-ray diffraction analysis, elemental analysis (EA), IR spectra (IR), powder X-ray diffraction (PXRD), and thermogravimetric (TG) analysis. The X-ray diffraction analysis reveals that complex 1 is an interesting (3,3,5,6)-connected 2D network of point symbol (3·4 2 ) 2 (3·4 3 ·5 2 ·6 3. 7) 2 (3 2 ·4 2 ·5 2 ·6 2 ·7 2 ·8 2 ·9 3 )(4 2 ·6) 2 , and the complex 2 is a 4-connected 3D dia framework of point symbol (6 6 ). Furthermore, the magnetic property of 1 , and luminescence sensing of complexes 1 and 2 for small organic molecules were also investigated. [ABSTRACT FROM AUTHOR]

Abstract: By employing asymmetric dicarboxylate and flexible N-donor ligands, four new coordination polymers, namely, Zn(ptmb)0.5(hpht)(H2O) (1), Cd2(ptmb)0.5(hpht)2(H2O) (2), [Co(ptmb)0.5(hpht)(H2O)2]·H2O (3), [Ni(ptmb)(hpht)(H2O)2]·H2O (4), (ptmb=1,4-bis(1,2,4-triazol-1-yl-methyl)benzene and H2hpht=homophthalic acid) have been synthesized. The networks feature diverse structures and coordination modes at the metal ions. Complex 1 is a deeply corrugated 2D layer structure of hcb topology, while the complex 2 presents the example of 3D sxd topological architecture. Complex 3 and 4 are both 2D sql topology, where 3 is a 2D structure with large Co6 honeycomb hexagon. In complex 4, the X–H⋯π (X=C, O) interactions exist and stabilize the stack of their 2D network. In all complexes, various non-covalent interactions are found and play important roles in structure expansion and stabilization. The structural diversities are discussed. TGA and XPRD of title complexes as well as the photoluminescent properties of complexes 1 and 2 are studied in the solid state at room temperature. [Copyright &y& Elsevier]