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Six different polyoxotungstate-based transition metal complexes were synthesized, namely [Cu5(2,2′-bpy)5(μ2-Cl)2(PO4)2(H2O)2][HPW12O40]·2H2O (1), [Cu1.5(2,2′-bpy)1.5(inic)2(H2O)1.5]3[H1.5PW12O40]2·16.25H2O (2), [Cu(2,2′-bpy)2]2[SiW12O40]·10H2O (3), [Zn(phen)3]2[PWVW VI11 O40]·5H2O (4), [Zn(phen)2(H2O)]2[SiW12O40]·2H2O (5), and [Zn(2,2′-bpy)2]2[SiW12O40] (6) (2,2′-bpy = 2,2′-bipyridine, inic = isonicotinic acid, phen = 1,10-phenanthroline). Compound 1 is based on [HPW12O40]2− anions, which are accommodated within the open channels of a supramolecular network formed by novel Cu–P–Cl coordination clusters. Compound 2 is constructed from [H1.5PW12O40]1.5− and novel [Cu1.5(2,2′-bpy)1.5(inic)2(H2O)1.5]+ coordination fragments, and polyoxoanions are encapsulated within the pores created by the copper coordination fragments, resulting in a unique three-dimensional supramolecular architecture. Compound 3 is a two-dimensional structure formed through the covalent linkage between [SiW12O40]4− and [Cu(2,2′-bpy)2]2+. Compound 4 is a supramolecular architecture formed by [PWVW VI11 O40]4− and [Zn(phen)3]2+ coordination fragments, while compound 5 is a supramolecular structure based on POM bi-supported Zn coordination complexes. Compound 6 is a two-dimensional framework structure constituted by [SiW12O40]4− and [Zn(2,2′-bpy)2]2+via covalent interactions. In addition, electrochemical measurement results show that the copper-based tungstate compounds 1–3 and zinc-based tungstate compounds 4–6 exhibit different performances and durabilities as electrochemical capacitors (compound 1 shows the highest specific capacitance of 94.0 F g−1 at 1.5 A g−1, whereas compound 6 maintains the best cycling stability with the capacity retention of 80.7% after 1000 cycles at 4 A g−1.). This study contributes to the development of POM-based transition metal complexes with high capacitance by providing insights into the design and synthesis process. [ABSTRACT FROM AUTHOR]

Three compounds based on Ge-V-O clusters were hydrothermally synthesized and characterized by IR, UV-Vis, XRD, ESR, elemental analysis and X-ray crystal structural analysis. Both [Cd(phen)(en)]2[Cd2(phen)2V12O40Ge8(OH)8(H2O)]∙12.5H2O (1) and [Cd(DETA)]2[Cd(DETA)2]0.5[Cd2(phen)2V12O41Ge8(OH)7(0.5H2O)]∙7.5H2O (2) (1,10-phen = 1,10-phenanthroline, en = ethylenediamine, DETA = diethylenetriamine) are the first Ge-V-O cluster compounds containing aromatic organic ligands. Compound 1 is the first dimer of Ge-V-O clusters, which is linked by a double bridge of two [Cd(phen)(en)]2+. Compound 2 exhibits an unprecedented 1-D chain structure formed by Ge-V-O clusters and [Cd2(DETA)2]4+ transition metal complexes (TMCs). [Cd(en)3]{[Cd(η2-en)2]3[Cd(η2-en)(η2-μ2-en)(η2-en)Cd][Ge6V15O48(H2O)]}∙5.5H2O (3) is a novel 3-D structure which is constructed from [Ge6V15O48(H2O)]12− and four different types of TMCs. We also synthesized [Zn2(enMe)3][Zn(enMe)]2[Zn(enMe)2(H2O)]2[Ge6V15O48(H2O)]∙3H2O (4) and [Cd(en)2]2{H8[Cd(en)]2Ge8V12O48(H2O)}∙6H2O (5) (enMe = 1,2-propanediamine), which have been reported previously. In addition, the catalytic properties of these five compounds for styrene epoxidation have been assessed. [ABSTRACT FROM AUTHOR]

Three compounds, [AsMo8V6O42][Cu(2,2ʹ-bpy)2]2[Cu(2,2ʹ-bpy)]·4H2O (1), [PMo8V6O42][Cu(2,2ʹ-bpy)2]2[Cu(2,2ʹ-bpy)]·3H2O (2) and [PMo8V6O42][Cu(2,2ʹ-bpy)2]2[Cu(2,2ʹ-bpy)]·3.5H2O (3), have been synthesized under hydrothermal conditions and characterized by IR, UV–vis, XRD, TG, elemental analysis, and X-ray diffraction analysis. Single-crystal X-ray structure analysis reveals that1and2are isostructural and isomorphous, whereas2and3are polymorphs. Polymorphs of1have not been synthesized yet. The mixed-valent transition metal ion in1–3has been further confirmed by TG analyses. Catalytic properties of1and2have also been studied. [ABSTRACT FROM PUBLISHER]

Two new compounds, [CuCl(Phen)(H2O)][PW12O40][4,4′-H2bpy]·1.5H2O (1) and [Cd2(Phen)4Cl2][HPMo12O40](4,4′-bpy) (2) (bpy = bipyridine, Phen = phenanthroline), have been hydrothermally prepared and characterized by IR, UV–vis, XPS, XRD, elemental analysis, cyclic voltammetry analysis, and single-crystal X-ray diffraction analysis. Compound1exhibits a 1-D chain structure constructed from polyoxometalates (POMs) and transition metal complexes, whereas2presents a supramolecular structure constructed from POMs, metal halide clusters, and organic ligands. [ABSTRACT FROM AUTHOR]

Three novel heteropolyanions [PMo12Sb2O40][Cu(enMe)2]·4H2O (1), [PMo12Sb2O40][Ni(enMe)2]·4H2O (2) and [PMo12Sb2O40][Cu(en)2]·H3O·H2O (3) (enMe = 1,2-diaminopropane, en = ethylene diamine) have been synthesized and characterized by IR spectroscopy, X-ray photoelectron spectroscopy (XPS), thermogravimetric analyses and elemental analyses. Single-crystal X-ray diffraction analyses reveal that these three compounds represent the first examples of compounds based on the novel polyoxoanion {PMo12Sb2O40} and different transition metal coordination complexes. 1and 2are isostructural and both exhibit novel 1-D structures. In contrast to 1and 2, 3exhibits a substantially distinct novel 1-D structure. In addition, 3is the first example of an extended structure constructed from polyoxoanions and Cu+transition metal coordination complexes. [ABSTRACT FROM AUTHOR]

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 polyoxometalates (1) and (2) (en=ethylenediamine, phen=1,10-phenanthroline) have been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction, IR, EPR, XPS, elemental analysis and thermogravimetry. Their structures exhibit interesting 3D supramolecular networks, and contain new bicapped (pseudo-) Keggin-type tungsten–vanadium cluster and the template transition-metal complexes (TMCs) being generated in situ under mild hydrothermal conditions. Interestingly, compound 1 contains four different kinds of nickel complex countercations. [Copyright &y& Elsevier]

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]

Three new compounds based on arsenic–vanadium clusters {[Cu(im) 2 ] 4 [H 2 As 8 V 14 O 42 (SO 4 )]}·H 2 O ( 1 ) and [Cu(phen)(im)] 3 [Cu(phen) 2 ][As 8 V 14 O 42 (H 2 O)] ( 2 , 3 ) (im = imidazole, phen = phenanthroline) have been synthesized and characterized by IR, UV–Vis, XRD, TG analysis, elemental analysis, single-crystal X-ray diffraction analysis and catalytic properties. Crystal analysis reveals that compound 1 shows an unprecedented 3-D twofold interpenetrating network structure with each of the two interpenetrating frameworks exhibiting a novel diamondoid framework structure based on POMs and transition metal complexes. Compounds 2 and 3 are based on identical polyanions and identical transition metal complexes. However, the two compounds are not isomorphous and isostructural with each other. That is to say, the two compounds have an identical chemical formula with different structures: the two are polymorphs of each other. In addition, catalytic properties of compounds 1 – 3 have been studied. [ABSTRACT FROM AUTHOR]

Abstract: Four new organic–inorganic hybrid compounds based on bicapped Keggin polyoxometalate {PMo12Sb2O40}: [H24,4′-bpy][PMo12Sb2O40]·6H2O (1), [Him]2[PMo12Sb2O40]·H2O (2), [H3(DABCO)2][PMo12Sb2O40]·2H2O (3) and [Mn(phen)3][PMo12Sb2O40] (4) (bpy=bipyridine, im=imidazole, DABCO=1,4-diazabicyclo[2,2,2]octane, phen=phenanthroline) 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. The four compounds are new examples of hybrid compounds based on bicapped Keggin polyoxometalate {PMo12Sb2O40}. Compound 1, 2 and 3 are constructed from {PMo12Sb2O40} anions and different organic moieties, respectively. Compound 4 is formed by combining {PMo12Sb2O40} anions and manganese coordination complexes. [Copyright &y& Elsevier]

Abstract: Two new hybrid compounds based on Keggin-type polyoxometalates: {[PMo12O40][Ni(Phen)2(H2O)]2}·K·2OH− (1) and [Cd2(Phen)4Cl2][HPW12O40]·H2O (2) (Phen=1,10-phenanthroline), have been prepared and characterized by IR, UV–vis, XPS, XRD and single crystal X-ray diffraction analyses. Compound 1 exhibits a 1-D chain structure constructed from Pseudo-Keggin polyoxometalate bi-supported transition metal coordination complexes linked by K+ ions. Compound 2 contains Pseudo-Keggin polyoxoanions [HPW12O40]2− and novel metal–chloride–ligand coordination complexes [Cd2(Phen)4Cl2]2+. [Copyright &y& Elsevier]

Abstract: A new compound [Mo8V7O42][Cu(2,2′-bpy)2]2[Cu(2,2′-bpy)]·2H3O (1) has been synthesized under hydrothermal conditions and characterized by IR, UV–vis spectrum, elemental analysis, XRD, ESR, XPS, X-ray diffraction analysis and magnetic property study. Single-crystal X-ray structure analysis indicates that the compound 1 is a novel Keggin polyoxoanion tri-supported mixed-valent transition metal coordination complex. [ABSTRACT FROM AUTHOR]

Abstract: A novel polyoxometalate (1) has been hydrothermally synthesized and characterized by elemental analysis, IR spectrum, ESR spectrum and single crystal X-ray diffraction analysis. It is a novel Weakley-type POM supported transition metal coordination complex, also it contains a novel (H2O)14 water cluster in the structure. The study of the magnetic susceptibility of 1 demonstrates the presence of ferromagnetic interactions. [Copyright &y& Elsevier]

Abstract: A novel compound [P2W18M3O68][Cu(en)2]4·7H2O·2OH− (M=0.5W+0.5Cu) 1 which contains the first example of extended structure constructed from Knoth-type sandwich polyoxoanions and transition metal coordination complexes has been hydrothermally synthesized and characterized by elemental analysis, IR spectrum, UV–Vis spectrum and single-crystal X-ray diffraction analysis. Crystal data for 1: triclinic, space group, P-1, a =13.2718(7)Å, b =13.6432(8)Å, c =25.7307(15)Å, α =104.7340(10)°, β =96.7630(10)°, γ =90.0330(10)°, V =4472.2(4)Å3, Z =2. Structure solution and refinement based on 1090 parameters gave R1 (wR2)=0.0409 (0.0993). [Copyright &y& Elsevier]

Five new compounds based on {XM 12 O 40 } (X ​= ​P, Si, M ​= ​W, Mo) were synthesized and characterized by IR, UV–Vis, XRD, cyclic voltammetry and single crystal X-ray diffraction analysis. [Cd 2 (phen) 4 (inic)(Cl)][HPW 12 O 40 ] (1 , inic ​= ​isonicotinic acid, phen ​= ​1,10-phenanthroline), [Cd 2 (phen) 4 (inic)(Cl)][HPMo 12 O 40 ]∙H 2 O (2), and [Cd 2 (phen) 4 (nic)(Cl)][HPMo 12 O 40 ]∙H 2 O (3 , nic ​= ​nicotinic acid) are isostructural and isomorphous to one another. Compounds 1 and 2 are both constructed from [XM 12 O 40 ]3- and transition metal mixed-organic-ligand complexes (TMMCs) of inic−, whereas compound 3 is formed by [XM 12 O 40 ]3- and TMMCs of nic−. [Cd 2 (phen) 4 (pic)][PMo 12 O 40 ] (4 , pic ​= ​picolinic acid) is made up of [PMo 12 O 40 ]3- and supported cadmium-pic-phen complexes. [Ag(py) 2 ] 0.75 [H 3.25 SiW 12 O 40 ](py) (5 , py ​= ​pyridine) is based on [H 3.25 SiW 12 O 40 ]-0.75 and silver complexes of py. It should be noted that py ligands in compound 5 are in-situ synthesized from pic hydrothermally. The photodegradation properties for compounds 1 – 5 have been studied. Five new compounds constructed from Keggin polyoxoanions and cadmium (silver) complexes have been synthesized and characterized. Image 1 • New Compounds based on polyoxometalates and cadmium mixed-organic-ligand complexes. • Mixed ligand complexes of both nitrogen-containing and pyridinecarboxylate organic ligands. • Compounds with isostructural and isomorphous structure formed by different organic ligands. [ABSTRACT FROM AUTHOR]