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A polyoxometalate [Co(phen)3][Co(en)3][Co(en)2(H2O)2][Co(en)2]0.5[ [image omitted]O40(VIVO)2] · 6H2O (1) (en = ethylenediamine, phen = 1,10-phenanthroline) has been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction, IR, electron paramagnetic resonance, X-ray photoelectron spectroscopy, elemental analyses, and thermogravimetry. The structure is an interesting 3-D supramolecular network containing bi-capped Keggin-type molybdenum-vanadium clusters with transition metal complexes generated in situ under mild hydrothermal conditions. Compound 1 contains four different counteractions being coordinated complexes of cobalt. The magnetic properties of 1 have also been studied in the temperature range of 4-300 K, and its magnetic susceptibility obeys the Curie-Weiss law, showing ferromagnetic coupling. [ABSTRACT FROM AUTHOR]

Two new polyoxometalates [HN(C2H5)3]3[PMo12O40] (1) and [NH2(C2H4NH3)2]2[Mo5P2O23] (2) have been hydrothermally synthesized and characterized by IR, UV-Vis, XPS spectra, TG analyses, and single crystal X-ray diffraction. Crystal data for 1: monoclinic, space group C2/c, a = 24.651(5) Å, b = 10.822(2) Å, c = 22.413(5) Å, β = 120.37(3)°, and V = 5158.7(18) Å3; for 2: triclinic, space group P-1, a = 9.821(2) Å, b = 9.948(2) Å, c = 14.687(3) Å, α = 95.490(3)°, β = 98.870(3)°, γ = 95.710(3)°, and V = 1401.7(5) Å3. The crystal structure analyses reveal complex hydrogen bonds in both 1 and 2 in 3-D supramolecular arrays constructed from different polyoxoanions and organic ligands. [ABSTRACT FROM AUTHOR]

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]

Three new supramolecular compounds, [Cu( o -HPIDC)(bpy)(H 2 O)]·2H 2 O 1 , [Cu( o -H 2 PIDC)(phen)Cl]·[Cu(phen) 2 Cl]·10H 2 O·Cl 2 and {[Cd( o -H 2 PIDC)(H 2 O) 2 Cl]·H 2 O} 2 3 ( o -H 3 PIDC = 2-(pyridine-2-yl)-1H-imidazole-4,5-dicarboxylic acid, bpy = 2,2'-bipyridine, phen = 1,10-phenanthroline), were hydrothermally synthesized and characterized. In compound 1 , the adjacent two supramolecular layers are constructed from different types of helical chains with the same pitch. In compound 2 , the adjacent 2D water-chloride layers, {[(H 2 O) 10 Cl] − } n , are pillared by [Cu( o -H 2 PIDC)(phen)Cl] units to form the overall 3D supramolecular network with 1D channels through O H⋯O hydrogen bond interactions. In compound 3 , two Cd(II) are linked into a binuclear [Cd 2 ( o -H 2 PIDC) 2 (H 2 O) 4 Cl 2 ] with a ten-membered ring by two o -H 2 PIDC − ligands. The three compounds self-assemble into 3D supramolecular structures via hydrogen bond and π-π stacking interactions. The fluorescence properties of compound 3 was also investigated. [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: 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: Two new supramolecular compounds based on tungsten–vanadium polyoxoanions formulated as [Cu(2,2′-bipy)3]2H14[PW2.2V9.8O40(VO)2[Cu(2,2′-bipy)2H2O]2][PW2.2V9.8O40(VO)2]·10H2O (1) and [Cu4(2,2′-bipy)4(H2O)2(PO4)2]H6.5[PW8.4V3.6O40]·2H2O (2) (2,2′-bipy=2,2′-bipyridine) have been synthesized hydrothermally and characterized by IR, TG, XPS and X-ray diffraction analyses. Crystal structure analyses reveal that compounds 1 and 2 exhibit novel 2D supramolecular layer structures constructed from tungsten–vanadium polyoxoanions and different types of secondary building units (SBUs), respectively, the different SBUs are formed by [Cu(2,2′-bipy)2H2O]2+ and [Cu(2,2′-bipy)3]2+ cations in compound 1 and [Cu4(2,2′-bipy)4(H2O)2(PO4)2]2+ cations in 2, respectively. Study of magnetic properties indicated the presence of antiferromagnetic behaviors for both compound 1 and 2. [Copyright &y& Elsevier]

By hydrothermal method, a novel supramolecular compound, Co(NIA)2(H2O)4 was synthesized and its structure was characterized with elemental analysis, FT-IR spectrum, TGA and X-ray diffractometer, indicating that it is a novel polyporous supramolecule with molecular ladder hydrogen-bonded chains. TGA curve shows its thermal stability up to 520 °C. [Copyright &y& Elsevier]