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Two supramolecular compounds [Fe(2,2'-bipy)3]2[ [image omitted](Cl)] · 4.67H2O (1) and [Ni(enMe)3]2[ [image omitted](Cl)] · 2H2O (2) have been prepared under hydrothermal conditions and characterized by elemental analyses, IR, TGA, ESR, magnetic properties, and single crystal X-ray diffraction analyses. Crystal data for 1: tetragonal, I-42d, a = 13.6043(19), b = 13.6043(19), c = 50.544(10) Å, V = 9354(3) Å3; for 2: hexagonal, P6(3)/m, a = 12.6046(12), b = 12.6046(12), c = 22.563(5) Å, V = 3104.4(7) Å3. Compound 1 is constructed from cations [Fe(2,2'-bipy)3]3+, polyoxovanadates [ [image omitted](Cl)]6-, and water molecules. Compound 2 is composed of cations [Ni(enMe)3]2+, clusters [ [image omitted](Cl)]8-, and water molecules. There are hydrogen-bonding interactions between polyoxovanadates, organic moieties, and/or water molecules in 1 and 2, forming different 2-D layered networks. [ABSTRACT FROM AUTHOR]

Abstract: Two new molybdenum–vanadium polyoxometalate tri-supported transition metal complexes [Cu(2,2′-bipy)] [Cu(2,2′-bipy)2]2[PMo8V6O42]·nH2O (n =1.5 (1) and n =2 (2); 2,2′-bipy=2,2′-bipyridine) have been hydrothermally synthesized and characterized by elemental analyses, IR, XPS and single-crystal X-ray diffraction analyses. Both compound 1 and compound 2 contain molybdenum–vanadium polyoxometalates, each of which support one [Cu(2,2′-bipy)]2+ cation and two [Cu(2,2′-bipy)2]2+ cations, respectively. The difference between compound 1 and compound 2 is that the polyoxoanion of 1 is a bi-capped α-Keggin cluster and that of 2 is a bi-capped pseudo-Keggin one. Studies of magnetic properties indicated the presence of ferromagnetic behaviors for compounds 1 and 2. [Copyright &y& Elsevier]

Based on an aim of introducing the SCN − or SO 4 2 − group into the organically templated chlorocadmates, a series of room-temperature reactions at pH 2 were performed, creating four new Cd(II) hybrids as [L1] 4 [Cd 4 Cl 6 (SCN) 10 (H 2 O) 2 ] (L1 = 1,1′-dibenzyl-4,4′-bipyridium) 1 , [H 4 L2][CdCl 4 (SCN) 2 ] (L2 = 1,4-bis(4-pyridylmethyl)piperazine) 2 , [HL3] 3 [CdCl 3 ]SO 4 (L3 = 2-amino-6-chloropyridine) 3 , and [HL4] 3 [CdCl 3 ]SO 4 (L4 = 2-amino-6-bromopyridine) 4 . X-ray single-crystal diffraction analysis reveals that (i) templated by L1 2+ , 1 shows a 1-D single-chain structure, which is based on the dinuclear [Cd 2 Cl 3 (SCN) 4 (H 2 O)] 3 − clusters by the μ-1,3-mode SCN − groups; (ii) templated by H 4 L2 4+ , 2 only exhibits a mononuclear structure. However, via the intermolecular weak N pyridine H⋯Cl, N piperazine H⋯Cl and S SCN ⋯S SCN interactions, 2 self-assembles into a 3-D supramolecular network with a (4,6)-connected topology; (iii) 3 and 4 possess the similar structures. Via the N pyridine/amino H⋯O and π⋯π interactions, the introduced SO 4 2 − groups and the organic base molecules aggregate together into a 3-D supramolecular network with the 1-D channels. Within the channel, the Cl − ions triplely bridge the Cd 2+ centers into a 1-D linear [CdCl 3 ] − chain. Based on the structural information and the previous related reports, the role of the introduced SCN − or SO 4 2− group in the hybrid is revealed. SCN − acts as two roles: (i) a linker; (ii) a cutter. Sometimes SO 4 2− serves as a linker, while sometimes SO 4 2− connects with organic base into a supramolecular aggregation, acting as a new templating agent. The photoluminescence analysis reveals that 2 , 3 and 4 emit light with the maxima at 535 nm for 2 ( λ ex = 465 nm), 462 nm for 3 ( λ ex = 428 nm), and 465 nm for 4 ( λ ex = 430 nm), respectively. In particular, the emissions for all are strong, and can be seen under the ultraviolet (UV) lamp. [ABSTRACT FROM AUTHOR]

Abstract: Four new supramolecular architectures based on Keggin polyoxometalates (POMs): [(HSiMo12O40)(H4,4′-bpy)2][(H4,4′-bpy)(H2O)2]·2H2O (1), [(HSiW12O40)(H4,4′-bpy)2][(H4,4′-bpy)(H2O)2]·2H2O (2), [(SiW12O40)(H4,4′-bpy)4]·(4,4′-bpy)·2H2O (3) and [H4SiW12O40](2,2′-bpy)4 (4) (bpy=bipyridine) have been prepared hydrothermally and characterized by IR, UV–Vis spectroscopy, X-ray photoelectron spectroscopy (XPS), powder XRD analyses, elemental analyses, fluorescence analysis and single crystal X-ray diffraction analyses. Both compounds 1 and 2 exhibit supramolecular 2D layer structures. Compound 3 exhibits a novel supramolecular double chain structure. Compound 4 contains a 1D chain structure with two 2,2′-bpy ligands as double bridges. It should be noted that compound 4 is the first example of hybrid compound based on 2,2′-bpy ligands and POMs. [Copyright &y& Elsevier]

Abstract: The first example of cadmium complex containing methyl orange [MO, (CH3)2NC6H4N=NC6H4SO3Na], formulated as [Cd(en)2(H2O)2](MO)2 1 (en=ethylenediamine) was synthesized hydrothermally and characterized by single-crystal X-ray diffraction, IR, XRD, elemental analysis and Raman spectroscopic analysis. Compound 1 display a two-dimensional supramolecular layer structure with ladder-like supramolecular chain by X-ray crystallographic analysis. MO anion immobilized by H-bonds, as acid–base indicator, shows a similar behavior in comparison with its solution counterpart in terms of response to pH. [Copyright &y& Elsevier]

Abstract: Two new zinc(II)–triazole–aliphatic dicarboxylate coordination polymers, [Zn(trz)(Hsuc)] n (1), [Zn2(trz)2(tar)] n (2), have been hydrothermally synthesized by reaction of Zn salt, Htrz with H2suc and H2tar, respectively (Htrz=1,2,4-triazole, H2suc=succinic acid, H2tar=tartaric acid). Their structures were determined by single-crystal X-ray diffraction analyses and further characterized by X-ray powder diffraction, elemental analyses, IR spectra and TG analyses. Compound 1 displays a 2D layer structure containing {[Zn4(trz)4]4+} n layers decorated by the suc ligand. Compound 2 is in a 3D structure formed by the interconnection of 2D {[Zn4(trz)4]4+} n layers with tar ligand, resulting a 3,4-connected topological network. Due to the different coordination mode and conformation of aliphatic carboxylate ligand, the similar 2D {[Zn4(trz)4]4+} n layers stack in the –AAA– fashion in 1, while the {[Zn4(trz)4]4+} n layers hold together in the –ABAB– stacking sequence in 2. Additionally, the two compounds show strong fluorescence in the solid state at room temperature. [Copyright &y& Elsevier]

Abstract: A novel compound 1 which represents the missing link between the discrete POMs and the POMs as building blocks in extended structure has already been hydrothermally synthesized and characterized by elemental analysis, IR, UV–Vis, XPS spectrum, TG analysis and single-crystal X-ray diffraction analysis. The study of the magnetic susceptibility of the compound 1 demonstrates the presence of ferromagnetic interactions. [Copyright &y& Elsevier]

Abstract: Two novel polyoxometalate derivatives, {X IVWVI 10WV 2O40[Cu(en)2(H2O)]3} [X=V (1), Si (2); en=ethylenediamine], have been hydrothermally synthesized and characterized by elemental analyses, IR, UV–Vis, XPS, EPR, TG and single crystal X-ray diffraction analyses. They represent the first classical Keggin polyoxoanion supported by three transition metal complex moieties, which further act as the neutral molecular unit for the construction of the interesting three-dimensional supramolecular frameworks. The magnetic properties of 1 have also been studied in the temperature range of 4–300K, and its magnetic susceptibility obeys the Curie–Weiss law, showing antiferromagnetic coupling. [Copyright &y& Elsevier]

Abstract: A novel 3-D magnesium metal–organic framework [Mg1.5(μ5-btec) (H2O)2]·[H2N(CH3) 2]·H2O (btec=1,2,4,5-benzenetetracarboxylic acid) has been synthesized under solvothermal conditions, and characterized by single-crystal X-ray structure determination, thermogravimetric analysis, X-ray powder diffraction, IR, and photoluminescent studies. [Copyright &y& Elsevier]