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A nanoscale polyoxoniobate based on trivalent nickel complex and Lindqvist-type cluster, [Ni(en)3]2[H2Nb6O19]·8H2O (abbreviated as NEN) (en = ethylenediamine, C2H8N2) has been synthesized and structurally characterized by elemental analyses, IR spectrum, UV–visible spectra, X-ray photoelectron spectrum (XPS), thermogravimetric analysis (TGA) and single-crystal X-ray diffraction. Structural analysis shows that NEN is an ionic compound, in which the cations are two trivalent nickel complexes [Ni(en)3]3+ and the anion is a Lindqvist-type polyoxoniobate [Nb6O19]8− cluster. Notably, NEN can catalyze the production of reactive oxygen species efficiently in aqueous solution system. [ABSTRACT FROM AUTHOR]

Three oxalate-bridging lanthanide-based polyoxometalates (Ln-POMs) K17Na2H5[{(As2W19O67(H2O))Ln(H2O)2}2(C2O4)]·50H2O. [Ln = Sm3+ (1), Pr3+ (2), and Ce3+ (3)] were successfully synthesized. The structures were further characterized by single-crystal X-ray diffraction analyses, Raman spectroscopy, elemental analyses, powder X-ray diffraction (PXRD), IR spectra, UV/vis diffuse reflectance spectroscopy, and thermogravimetric analysis (TGA). The structural characterization study reveals that Ln-POMs 1–3 crystallize in the form of the triclinic space group P1¯ and consist of an oxalate bridging di-Ln3+-incorporated H-shaped dimer, which can also be viewed as a combination of two half-units {Ln(As2W19O67(H2O))(H2O)2}222− related by an inversion center. It is worth noting that the opening angle (33.01°) from the [As2W19O67(H2O)]14− fragment in 1–3 is less than that of the [As2W19O67(H2O)]14− precursor (40.99°). Furthermore, the stability of 1–3 in aqueous solution and their solid-state photoluminescence properties have also been investigated in this work. [ABSTRACT FROM AUTHOR]

A high-nuclearity nickel-substituted polyoxotungstate, Na6K5.5H4.5 {[Ni8(OH)6(H2O)2](CO3)3(SiW9O34)2}·22H2O (1), has been obtained by the reaction of Na10[α-SiW9O34]·18H2O, Ni(NO3)2·6H2O and K2CO3 in aqueous solution and characterized by IR spectroscopy, single crystal X-ray diffraction, thermal gravimetric analysis and elemental analysis. Carbonate is not only used to adjust the pH of the solution, but also is a structure-stabilizing agent. The polyoxoanion {[Ni8(OH)6(H2O)2](CO3)3(SiW9O34)2}16- (1a) can be regarded as two {[Ni4(OH)3(H2O)](SiW9O34)} subunits connected by three carbonate groups, which represents the first polyanion containing an octanuclear nickel cluster based on trivacant Keggin-type polyoxotungstate {XW9} (X = heteroatom). The subunit {[Ni4(OH)3(H2O)](SiW9O34)} can be viewed as a tetranuclear nickel cluster linked to a trivacant Keggin-type polyoxotungstate {SiW9O34}. Furthermore, magnetic measurements show that 1 exhibits antiferromagnetic interactions. [ABSTRACT FROM AUTHOR]

The first example of wholly inorganic ruthenium-containing polyoxomolybdate Cs3Na6H[MoVI14RuIV2O50(OH)2]·24H2O (1) was isolated and systematically characterized by element analysis, infrared spectroscopy (IR), thermogravimetric analyses (TGA), X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDX) and single-crystal X-ray diffraction. Compound 1 is composed of an unprecedented {Mo14}-type isopolymolybdate with a di-ruthenium core precisely encapsulated in its center, exhibiting a three-tiered ladder-like structure. The title compound can act as an efficient heterogeneous catalyst in the transformation of 1-phenylethanol to acetophenone. This catalyst is also capable of being recycled and reused for at least ten cycles with its activity being retained under the optimal conditions. [ABSTRACT FROM AUTHOR]

A novel organic-inorganic hybrid polyoxometalate-based 3D framework K 5 H 4 {Ce 3 (H 2 O) 9 [As 2 W 21 O 72 (mal) 2 ]}·20H 2 O (1) (mal = malic acid) has been synthesized by the metastable precursor [As 2 W 19 O 67 (H 2 O)] 14 − , which was further characterized by IR spectrum, thermogravimetric analysis (TGA), and X-ray single-crystal diffraction. Structural analysis revealed that 1 consists of the organo-functionalized [As 2 W 21 O 72 (mal) 2 ] 18 − units linked together by the Ce 3 + ions resulting in 3D network-like architecture. Magnetic property studies indicate that obvious antiferromagnetic interactions exist in three Ce 3 + ions. [ABSTRACT FROM AUTHOR]

A novel octa-nuclear cerium(III)-containing organic-inorganic hybrid polyoxometalate [N(CH 3 ) 4 ] 8 H 16 [{Ce( η 1 -C 6 H 5 NO 2 ) 2 (H 2 O) 6 [Ce(H 2 O) 3 ( α 2 -P 2 W 17 O 61 )]}{Ce( η 2 -C 6 H 5 NO 2 ) 2 (H 2 O) 5 [Ce(H 2 O)( α 2 -P 2 W 17 O 61 )]}] 2 ·90H 2 O (C 6 H 5 NO 2 = isonicotinic acid) ( 1 ) was obtained, which had been hydrothermally synthesized and characterized by IR spectrum, thermogravimetric analysis (TGA), and X-ray single-crystal diffraction. Structural analysis indicated at 1 is composed of four lacunary Dawson-type units [ α 2 -P 2 W 17 O 61 ] 10 − joined together by eight cerium cations forming an uncommon zigzag tetrameric structure with eight isonicotinic acids as the organic pendants coordinating to the cerium cations. Magnetic property studies indicate that obvious antiferromagnetic interactions exist in eight Ce 3 + cations. [ABSTRACT FROM AUTHOR]

Two new organic–inorganic polyoxometalates [Cu(dien)(H2O)]2{[Cu2(dien)2(OH)]2[Cu4(B-α-XW9O33)2]}·4H2O (X = Sb,1;X = As,2) (dien = diethylenetriamine) were hydrothermally synthesized and characterized by elemental analysis, IR spectra, thermogravimetric (TG) analyses, and single-crystal X-ray diffraction. Both compounds are constructed from one four-coordinate [Cu(dien)(H2O)]2+, one {[Cu2(dien)2(OH)]2[Cu4(B-α-XW9O33)2]} building unit, and four water molecules of crystallization. Structural analysis shows that the sandwich-like polyoxotungstate cluster anions [Cu4(B-α-XW9O33)2]10−are linked by six adjacent dimeric cations [Cu2(dien)2(OH)]3+into a 2-D architecture with a (6,3)-connected topology. Magnetic measurements of1and2exhibit the presence of antiferromagnetic interactions within the tetranuclear-CuIIcluster. Two new organic–inorganic polyoxometalates with 2-D (6,3)-connected topology architecture [Cu(dien)(H2O)]2{[Cu2(dien)2(OH)]2[Cu4(B-α-XW9O33)2]}·4H2O (X = Sb,1;X = As,2) (dien = diethylenetriamine) were hydrothermally synthesized. [ABSTRACT FROM PUBLISHER]

Abstract: A novel Dy(III)-based organodiphosphonate-functionalized polyoxomolybdate [NH2(CH3)2]3{[Dy(DMF)2(H2O)4]3[Dy(DMF)3{(Mo3O8)(O3PCOCH3PO3)}3]2}∙6DMF·2H2O (1) (DMF=N,N-Dimethylformamide) has been synthesized and characterized by elemental analysis, IR spectrum, thermogravimetric analysis (TG), UV spectroscopy, fluorescence spectroscopy and single-crystal powder X-ray diffraction (PXRD). Compound 1 is composed of two monocapped [Dy(DMF)3{(Mo3O8)(O3PCOCH3PO3)}3]6− subunits and three [Dy(DMF)2(H2O)4]3+ coordination cations, which contain an internal capsule. The UV spectra indicate that compound 1 is stable in the pH range of 2.76–4.75. [Copyright &y& Elsevier]

By controlling the pH of the reaction system, a dilacunaryγ-Keggin silicotungstate [Cu(en)2(H2O)][H2en]{γ-SiW10O36[Cu(en)2(H2O)]2}·7.5H2O (1) (en = ethylenediamine) has been hydrothermally synthesized by the reaction of CuCl2withα-H4SiW12O40and characterized by IR spectra, thermogravimetric analysis, and single-crystal X-ray diffraction. The product is prepared in the pH range 7.9–8.2, which reveals that pH plays a key role in the assembly of saturatedα-H4SiW12O40to dilacunary [γ-SiW10O36]8−polyoxometalate. The polyoxoanion {γ-SiW10O36[Cu(en)2(H2O)]2]}4−of1presents a rare [γ-SiW10O36]8−-retaining structure, in which two lacunary sites of [γ-SiW10O36]8−are unoccupied, meanwhile, two [Cu(en)2(H2O)]2+groups are grafted on either side of the [γ-SiW10O36]8−unit by Cu–O–W bond. [ABSTRACT FROM AUTHOR]

An organic–inorganic coplanar-shaped hexa-CuII sandwiched hybrid, (H2en){[Cu(en)2]2[Cu2(en)2Cu4(H2O)2](B-α-AsW9O34)2} · 5H2O (en = ethylenediamine) (1), has been synthesized via hydrothermal method and further characterized by IR spectroscopy, thermogravimetric analysis, and X-ray single-crystal diffraction. Single-crystal X-ray diffraction analysis shows that 1 contains an organic–inorganic hybrid polyoxoanion {Cu2(en)2Cu4(H2O)2(B-α-AsW9O34)2}6−, which can be described as a coplanar-shaped hexa-CuII cluster sandwiched by two trivacant [B-α-AsW9O34]9− fragments. Complex 1 represents a rare organic–inorganic coplanar-shaped hexa-CuII cluster sandwiched arsenotungstate. Magnetic susceptibility measurements indicate that 1 demonstrates ferromagnetic coupling interactions within the CuII centers. [ABSTRACT FROM PUBLISHER]

Abstract: Two novel zinc coordination polymers [Zn2(H2O)L(MoO4)] n (1) and [Zn4(PO4)2L′(H2O)] n (2) (H2L=2,2′-bipyridine-6.6′-dicarboxylic acid, H2L′=2,2′-bipyridine-4,4′-dicarboxylic acid) have been hydrothermally synthesized and characterized by elemental analyses, IR spectra, UV spectra, single-crystal X-ray diffraction and thermogravimetric analyses. Structural analyses indicate that 1 represents a 2-D sheet structure built by dimeric [Zn2L(H2O)]2+ units and MoO4 2– groups whereas 2 displays an interesting 3-D framework constructed by tetranuclear zinc clusters, L′2− ligands and PO4 3– groups. Examination of UV spectra suggests that both 1 and 2 can stably exist in the pH range of 2.45–5.45 and 3.01–8.55 in aqueous solution, respectively. The room-temperature solid-state photoluminescence of 1 and 2 are derived from the intra-ligands π–π⁎ transitions of H2L and H2L′ ligands and the ligand-to-metal-charge-transfer transitions. [Copyright &y& Elsevier]

Abstract: A new two-dimensional (2D) polyoxoniobate K2[Cu(H2O)6]{[Nb6O19][Cu(NH3)]2}·8H2O (1) has been synthesized by the diffusion method and structurally characterized by elemental analyses, infrared (IR) spectrum, ultraviolet (UV) spectroscopy, X-ray photoelectron spectroscopy (XPS), thermogravimetric (TG) analysis and single crystal X-ray diffraction. Crystal structure analysis reveals that 1 exhibits a novel 2D network architecture constructed from Lindqvist-type [Nb6O19]8− polyoxoanions and copper coordinated cations. The XPS measurement indicates the oxidation state of Cu ion is +2. Surface photovoltage spectroscopy (SPS) and electric field induced surface photovoltage spectroscopy (EFISPS) measurements indicate that 1 possesses the n-type semiconductor characteristic. [Copyright &y& Elsevier]

Two 3d-4f heterometallic monovacant Keggin phosphotungstate derivatives [Cu(dap)(H2O)2]0.5[Cu(dap)2]4H2[Pr(α-PW11O39)2] · 3H2O (1) and [Cu(en)2(H2O)]2[Cu(en)2]1.5H4[Pr(α-PW11O39)2] · 10H2O (2) (dap = 1,2-diaminopropane, en = ethylenediamine) have been hydrothermally synthesized by reaction of the trivacant Keggin phosphotungstate precursor Na9[A-α-PW9O34] · 7H2O with CuCl2 · 2H2O and PrCl3 in the presence of dap or en and structurally characterized by elemental analyses, IR spectra, X-ray single-crystal diffraction, and thermogravimetric analyses. Compound 1 crystallizes in the triclinic space group P1 with a = 17.325(3), b = 18.917(3), c = 19.938(3) Å, α = 104.481(2), β = 98.968(3), γ = 91.306(3)°, V = 6236.4(18) Å3, Z = 2, GOOF = 1.000, R1 = 0.0806, wR2 = 0.2016. Compound 2 also belongs to the triclinic space group P1 with a = 16.005(4), b = 18.053(4), c = 21.127(5) Å, α = 113.894(3), β = 90.745(4), γ = 94.255(4)°, V = 5560(2) Å3, Z = 2, GOOF = 0.999, R1 = 0.0686, wR2 = 0.1885. Both 1 and 2 display organic-inorganic hybrid 2-D sheet architectures built by classic mono-PrIII sandwiched dimeric moieties [Pr(α-PW11O39)2]11- through [Cu(L)2]2+ bridges (L = dap, en), which represent rare organic-inorganic hybrid 2-D 3d-4f heterometallic monovacant Keggin polyoxometalates. [ABSTRACT FROM AUTHOR]

Two new organic-inorganic hybrid cobalt-molybdovanadates [Co(phen)3]H2[H2V2Mo6O26] · 7H2O (1) and [Co(2,2'-bipy)3][Na(H2O)7][VMo12O40] (2) have been hydrothermally synthesized and structurally characterized by elemental analyses, IR, UV, XPS spectroscopy, thermogravimetric (TG) analyses, and X-ray single crystal diffraction. The molecular structure of 1 consists of a [V2Mo6(OH)2O24]4- polyoxoanion, a [Co(phen)3]2+, two H+ and seven lattice water molecules. The structure of [V2Mo6(OH)2O24]4- consists of six MoO6 octahedra and two VO4 tetrahedra; six MoO6 octahedra are linked by edge-sharing oxygens forming a {Mo6} ring, and two VO4 tetrahedra cap opposite sides of the {Mo6} ring. The molecular structural unit of 2 is constructed from a typical Keggin-type [VMo12O40]3- polyoxoanion and a [Co(2,2'-bipy)3]2+ cation and a Na+ countercation; Co2+ is coordinated by six nitrogens from three 2,2'-bipyridines forming a distorted octahedron. [ABSTRACT FROM AUTHOR]

A new transition-metal (TM) complex of the Lindqvist polyanion Na[Cu(1, 3-pda)2]3[HNb6O19] · 3H2O (1, 3-pda = 1, 3-diaminopropane) has been prepared using pre-prepared TBA4[H4Nb6O19] · 7H2O as a precursor and characterized by single crystal X-ray diffraction, elemental analyses, IR spectra, and thermogravimetric analysis. Crystal data for the compound: rhombohedral, space group R-3c, a = 14.927(4) Å, b = 14.927(4) Å, c = 36.940(18) Å, γ = 120°, V = 7128(4) Å3, Z = 6. The structural unit of the title compound consists of a polyanion [HNb6O19]7-, a Na+, three [Cu(1, 3-pda)2]2+, and three crystal water molecules. The occupancy of all Cu atoms and water molecules is 0.5. X-ray diffraction indicated that the cations and the polyanion were linked through electrostatic interactions and intermolecular forces. [ABSTRACT FROM AUTHOR]

Twohybrid organic–inorganic organobisphosphonatepolyoxomolybdates, Na4H2[(Mo3O8)2(O){O3PC(O)(CH2-3-C5NH5)PO3}2]·12H2O (1) and Na8[(Mo3O8){O3PC(O)(CH2-3-C5NH5)PO3}]4·30H2O (2), have been successfullysynthesized and structurally characterized. Compounds 1and 2are prepared in aqueous solution by one-pot reactionof 1-hydroxo-2-(3-pyridyl) ethylidenebisphosphonate (risedronicacid) with molybdate. Structural analysis reveals that the two polyanionsare composed of the same building blocks and can be described as adimeric and tetrameric assembly of [(Mo3O8){O3PC(O)(CH2-3-C5NH5)PO3}]2–subunits, respectively.Elemental analysis, IR spectra, thermogravimetric analysis, and luminescenceproperties of the compounds have been studied in the solid state.The compounds are also characterized in the solution by multinuclear 31P NMR spectrometry, which evidences a subtle equilibriumbetween some species, and the results indicate that 1presents two conformers of these hexanuclear polyanions in solution,whereas 2is metastable, which might gradually decomposeinto one isomer of the dimer units. The photochromic property of 1is determined under ultraviolet (UV) irradiation of 365nm, and the sample develops a reddish coloration. [ABSTRACT FROM AUTHOR]

A series of organic–inorganic hybrid lacunaryKeggin silicotungstate3d-4f heterometallic derivatives, {[Cu (en)2]1.5Ln[(α-SiW11O39)2]}220–[Ln = GdIIIfor 1,TbIIIfor 2, DyIIIfor 3, ErIIIfor 4, LuIIIfor 5], {[Cu(en)2]1.5Ln[(α-SiW11O39)]}2–[Ln = LaIIIfor 6, CeIII, for 7] and {[Cu(en)2(H2O)][Cu(en)2]nLn[(α-SiW11O39)2]}m−[(Ln, n, m) = (PrIII, 2, 7) for 8, (SmIII, 3, 5) for 9] (en = ethylenediamine) havebeen successfully synthesized under hydrothermal conditions and furthercharacterized by elemental analyses, inductively coupled plasma atomicemission spectrometry (ICP-AES) analyses, X-ray powder diffraction(XRPD), IR spectra, thermogravimetric (TG) analyses, and single-crystalX-ray diffraction. The common features of 1–5and 8–9are that they allconsist of a sandwich-type [Ln(α-SiW11O39)2]13–polyoxoanion, whereas both 6and 7consist of the unusual 1:1 [Ln(α-SiW11O39)]5–units and [Cu(en)2]2犊⭶⧚똪 cations. 1–5show dimeric structures, and 6–9display unprecedented three-dimensional (3D) frameworks,representing the first 3D 3d-4f heterometallic silicotungstates. Thefeatures of 6and 7are that the componentsare closely packed along the 21screw axis to generatescarce 5-connected network structures with the Schläfli symbolof (48·62), while 8and 9exhibit the 4-connected (66) topology and 6-connected(48·54·63) topologystructures, respectively. Furthermore, 2, 3, and 9manifest apparent fluorescence signals, whichcan be assigned to the characteristic emissions of TbIII, DyIII, and SmIIIcations, respectively. [ABSTRACT FROM AUTHOR]

Abstract: Three novel organic–inorganic hybrid borotungstates {[Ni(phen)2(H2O)]2H(α-BW12O40)}·4H2O (1), [CuI(2,2''-bipy)(4,4′-bipy)0.5]2{[CuI(2,2′-bipy)]2CuI(4,4′-bipy)2(α-BW12O40)} (2) and {[CuI(4,4′-bipy)]3H2(α-BW12O40)}·3.5H2O (3) (phen=1,10-phenanthroline, 2,2′-bipy=2,2′-bipyridine, 4,4′-bipy=4,4′-bipyridine) have been hydrothermally synthesized and structurally characterized by elemental analyses, IR, UV spectra, powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA), single-crystal X-ray diffraction, X-ray photoelectron spectroscopy (XPS) and photoluminescence. The structural analysis reveals that 1 consists of a 0-D bisupporting polyoxometalate cluster where two [Ni(phen)2(H2O)]2+ cations are grafted on the polyoxoanion [α-BW12O40]5– through two terminal oxygen atoms, 2 shows a 1-D infinite chain constructed from [α-BW12O40]5– polyoxoanions and {[CuI(2,2′-bipy)]2CuI(4,4′-bipy)2}3+ cations by means of alternating fashion, and 3 displays an unprecedented 2D extended structure built by [α-BW12O40]5– polyoxoanions and –CuI–4,4′-bipy– linear chains, in which each [α-BW12O40]5– polyoxoanion acts as a tetradentate inorganic ligand and provides three terminal oxygen atom and one two-bridging oxygen atom. The presence of NiII and WVI in 1, CuI ions and WVI in 2 and 3 are identified by XPS spectra. The photoluminescence of 2 and 3 are also investigated. [Copyright &y& Elsevier]

A novel organic-inorganic hybrid dimeric tungstoantimonate [Cu(H 2 O) 4 ]{[Cu(bpy)] [Cu 3 (bpy) 3 (H 2 O)](SbW 9 O 33)} 2 ·15H 2 O (1) (bpy = 2, 2′-bipyridine) was synthesized by the metastable precursor [NaSb 9 W 21 O 86 ]18−, which was further characterized by IR spectrum, thermogravimetric analysis (TGA), and X-ray single-crystal diffraction. Structural analysis revealed that 1 consists of the two trivacant organo-functionalized {[Cu(bpy)][Cu 3 (bpy) 3 (H 2 O)](SbW 9 O 33)}− units linked together by one [Cu(H 2 O) 4 ]2+ group resulting in a dimeric architecture. Magnetic property studies indicate that obvious antiferromagnetic interactions above 25 K and weak ferromagnetic coupling interactions below 25 K in these paramagnetic Cu(II) ions. A new tungstoantimonate-based dimeric architecture is constructed by two trivacant organo-functionalized {[Cu(bpy)][Cu 3 (bpy) 3 (H 2 O)](SbW 9 O 33)}− units linked together by one [Cu(H 2 O) 4 ]2+. Unlabelled Image • New organic-inorganic hybrid dimeric tungstoantimonate • Constructed by two [SbW 9 O 33 ]9− units linked together by one [Cu(H 2 O) 4 ]2+ cation • [SbW 9 O 33 ]9− unit is decorated by one [Cu(phen)(H 2 O)]2+ and three [Cu(phen)]2+ group. • Displays four kinds of different coordination geometries [ABSTRACT FROM AUTHOR]

A new [P 2 W 16 O 59 ] 12− ({P 2 W 16 })-based polyoxometalate (POM) derivative (TMA) 10 H 5 [Ce 3 (H 2 O) 6 (P 2 W 16 O 59 ) 2 ]⋅41H 2 O ( 1 ) (TMA = tetramethyleneamine) was successfully synthesized, which has been characterized by single crystal X-ray diffraction analysis, elemental analyses, cyclic voltammetry, thermogravimetric analyses (TGA), IR spectroscopy and 31 P NMR spectroscopy. The single crystal X-ray diffraction analyses indicate that polyanion of 1 consists of two divacant {P 2 W 16 } units connected by one standard isosceles triangle {Ce 3 } bridging cluster via Ce O W and Ce O P linkages. The investigation of 31 P NMR spectroscopy shows the presence of two types of phosphorus in compound 1 . The study of magnetic susceptibility for 1 reveals the strong spin-orbital coupling and weak antiferromagnetic interactions exist in the three Ce 3+ ions. The photoluminescence study indicates that the presence of 5d → 4f electron transition of Ce 3+ ion in 1 . [ABSTRACT FROM AUTHOR]

A novel cubane-type Ni-substituted polyoxotungstate based on trivacant Dawson-type [P 2 W 15 O 56 ] 12 − unit with the formula of Na 4 H 4 [P 2 W 15 O 56 (W 0.5 Ni 3.5 )(OH) 6 (H 2 O) 3 ]·18.5H 2 O ( 1 ) has been synthesized in aqueous medium and characterized by IR spectroscopy, EDX spectrum, thermogravimetric analysis and magnetic measurements. Structural analysis indicates that 1 consists of a trivacant Dawson-type unit [P 2 W 15 O 56 ] 12 − incorporated in a cubane-type {Ni 3.5 W 0.5 O 7 (OH) 6 (H 2 O) 3 } group. Magnetic studies show that the ferromagnetic Ni Ni exchange interactions exist in the cubane-type cluster. [ABSTRACT FROM AUTHOR]

A one-dimensional linear chainlike phosphotungstate based on Dawson-type [P 2 W 17 O 61 ]10- building unit was synthesized, which exhibits reversible photochromic behavior. [Display omitted] • A one-dimensional linear chainlike phosphotungstate was synthesized. • Constructed by monolacunary Dawson-type [α 2 -P 2 W 17 O 61 ]10- unit. • Shows reversible photochromic property. A one-dimensional linear chainlike phosphotungstate based on Dawson-type [P 2 W 17 O 61 ]10- building unit [H 2 N(CH 3) 2 ]{Sm 2 (H 2 O) 15 [Sm(H 2 O) 3 (α 2 -P 2 W 17 O 61)]}⋅21H 2 O (1) was prepared under routine aqueous condition, which was further characterized by IR spectroscopy, elemental analysis, powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA) and UV–vis diffuse reflectance spectra. Single-crystal X-ray diffraction result illustrated that compound 1 displays a one-dimensional infinite chainlike architecture constructed by monolacunary Dawson-type [α 2 -P 2 W 17 O 61 ]10- building unit and Sm3+ connectors. The reversible photochromic property of 1 was tested under UV radiation, which was able to change from white to visible saturated blue in 2 min and recover the natural state after dark treatment for about 10 h. [ABSTRACT FROM AUTHOR]

An inorganic–organic hybrid hexa-copper-substituted germanotungstate Na2[Cu(dap)2]2[Cu(dap)2] {[Cu6(H2O)2(dap)2][B-α-GeW9O34]2}·4H2O (1) (dap=1,2-diaminopropane) has been hydrothermally prepared and characterized by elemental analyses, inductively coupled plasma atomic emission spectrometry (ICP–AES) analyses, IR spectra, powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA) and single-crystal X-ray diffraction. 1 displays the six-connected 3D network with the long topological (O′Keefe) vertex symbol is 4·4·64·4·4·4·4·64·4·4·4·64·4·4·4 and the short vertex (Schläfli) symbol of 41263. Magnetic measurements indicate that there are the overall ferromagnetic exchange interactions in the belt-like hexa-CuII cluster in 1. Furthermore, the electrochemical behavior and electrocatalysis of 1 modified carbon paste electrode (1-CPE) have been studied. The reductions of nitrite, bromate and hydrogen peroxide are principally mediated by the WVI-based wave. [ABSTRACT FROM AUTHOR]

A novel organic–inorganic hybrid sandwich-type germanotungstate [enH2]8[Fe4(en)(α-GeW9O34)2] [Fe4(en)2(α-GeW9O34)2]·en·14H2O has been synthesized by reaction of K8Na2[A-α-GeW9O34]·25 H2O, FeCl3, Ce(NH4)4(SO4)4·4H2O and en (en=ethylenediamine) under hydrothermal conditions and characterized by elemental analyses, IR spectrum, powder X-ray diffraction (PXRD), X-ray photoelectron spectroscopy (XPS) and single-crystal X-ray diffraction. To our knowledge, 1 represents the first organic–inorganic hybrid sandwich-type germanotungstate with discrete [Fe4(en)2(α-GeW9O34)2]8− polyoxoanions and 1-D [Fe4(en)(α-GeW9O34)2]n 8n− polymeric chains in polyoxometalate chemistry. Thermogravimetric curve of 1 between 25 and 700°C indicates two steps of weight loss. Variable-temperature magnetic susceptibilities of 1 exhibit the ferromagnetic interactions within the belt-like tetra-FeIII clusters mediated by the oxygen bridges. [ABSTRACT FROM AUTHOR]

Abstract: An organic–inorganic hybrid 1-D double-chain CuII–YIII heterometallic silicotungstate [Cu(dap)2(H2O)]2 {Cu(dap)2[α-H2SiW11O39Y(H2O)2]2}·10H2O (1) has been synthesized by reaction of Na10[A-α-SiW9O34]·18H2O, CuCl2·2H2O, YCl3 and dap (dap=1,2-diaminopropane) under hydrothermal conditions and characterized by elemental analyses, IR spectrum, UV spectrum and single-crystal X-ray diffraction. 1 exhibits a novel 1-D double-chain structure constructed from dimeric CuII–YIII heterometallic silicotungstate units. To our knowledge, 1 is the first organic–inorganic hybrid 1-D double-chain CuII–YIII heterometallic polyoxometalate. Thermogravimetry-differential thermal analysis of 1 has been measured from 25 to 750°C and the thermogravimetric curve indicates two steps of weight loss. [Copyright &y& Elsevier]

Abstract: Three lanthanide (Ln) substituted polyoxometalates [{(α-PW11O39H2)Ln(H2O)(η2,μ-1,1)-CH3COO}2]10− (Ln=Dy(III) for 1, Y(III) for 2, Lu(III) for 3) have been synthesized successfully in moderate aqueous solution and characterized by elemental analyses, IR spectra, UV spectroscopy, thermogravimetric analyses, fluorescence spectra, X-ray powder diffraction (XRPD) and single-crystal X-ray diffraction. The structure analyses reveal that 1–3 are isostructural and constructed by two mono-lanthanide substituted units [(α-PW11O39H2)Ln(H2O)(η2,μ-1,1)-CH3COO]5−, which are bridged by two (η2,μ-1,1)-acetato ligands. The solid-state photoluminescence properties of 1–3 were studied and the results indicate that only 1 demonstrates yellow luminescence. Magnetic measurements reveal that 1 shows spin–orbital coupling interactions and weak antiferromagnetic exchange interactions. [Copyright &y& Elsevier]

Six crystalline polyoxometalate-based three-dimensional(3D) metal–organicframeworks {[AgL4(DMF)][AgL4]2(PMo12O40)·DMF·3H2O}n(1), {[AgL4]3(PW12O40)·6H2O}n(2), {[AgL5]3(PMo12O40)·(CH3CN)3}n(3), {[AgL5(PW12O40)][AgL5(H2O)0.25(MeOH)0.25)][AgL5]0.5·DMF·(H2O)1.5}n(4), {[AgL6]3(PMo12O40)·DMF·H2O}n(5), and {[AgL7]3(PMo12O40)·DMF·(CH3CN)3}n(6) have been successfully synthesized based on one-dimensional (1D)coordination polymers constructed by the coordination of polydentateSchiff-base ligands and silver cations and saturated α-Kegginpolyoxoanion [PM12O40]3–(M= W, Mo) as building blocks, where L4, L5, L6, and L7are 2,5-bis(3-pyridyl)-3,4-diaza-2,4-hexadiene,1,4-bis(3-pyridyl)-2,3-diaza-1,3-butadiene, 2,5-bis(4-pyridyl)-3,4-diaza-2,4-hexadiene,and 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene, respectively. Compounds 1–6are structurally characterized byelemental analyses, IR spectroscopy, thermogravimetric analyses (TG),powder X-ray diffraction (XRD), and complete single-crystal X-raydiffraction analyses. The structures of 1–6exhibit 3D supramolecular networks formed by linking 1DAg-Schiff base chains and α-Keggin polyoxoanion units throughthe cooperativity of multiform supramolecular interactions, such asintermolecular Ag···O weak interactions, Ag···πinteractions, π···π interactions, and hydrogenbonds. The photoluminescent properties of 1–6have been investigated in the solid state. [ABSTRACT FROM AUTHOR]

Abstract: A novel 2-D organic–inorganic hybrid tetra-CoII-substituted sandwich-type Keggin germanotungstate {[Co(dap)2(H2O)]2[Co(dap)2]2[Co4(Hdap)2(B-α-HGeW9O34)2]}·7H2O (1) (dap=1,2-diaminopropane) has been hydrothermally synthesized and structurally characterized by elemental analyses, IR spectrum, UV spectrum, powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA) and single-crystal X-ray diffraction. Structural analysis shows that 1 displays a rare 2-D (4,4)-topological network constructed by tetra-CoII-substituted sandwich-type Keggin germanotungstate units and [Co(dap)2]2+ bridges. To our knowledge, 1 represents the first 2-D organic–inorganic hybrid cobalt-substituted sandwich-type polyoxotungstate. Magnetic preperties of 1 have been investigated. The decrease of the product of the molar magnetic susceptibility at higher temperatures results from the spin-orbit coupling of the CoII ion and/or the antiferromagnetic interactions whereas the maximum at the lower temperatures is indicative of the ferromagnetic interactions within the tetranuclear CoII spin cluster in the sandwich belt. [Copyright &y& Elsevier]

Abstract: A polyoxometalate cluster based on Strandberg-type phosphomolybdate [K3Ca(H2O)4(HP2Mo5O23)]·6H2O (1) has been synthesized by the conventional solution method and characterized by IR spectrum, UV spectra, electrochemical measurements, thermogravimetric analysis, ICP techniques and X-ray crystallography. X-ray single crystal diffraction analysis shows that 1 contains a novel polyoxoanion [Ca(H2O)4(HP2Mo5O23)]3− (1a) based on a Strandberg-type phosphomolybdate [HP2Mo5O23]5−. Notably, it represents the first 2D polymolybdate inorganic structure constructed from Strandberg-type phosphomolybdates linked through alkaline earth metal clusters. Interestingly, the phenomenon that 1a and heteropolyoxoanion {[Ca(H2O)]6[P4Mo6O34]2}12− can be mutually transformed when the pH of the solution is adjusted to ca. 4.50 in aqueous solution has been observed. [Copyright &y& Elsevier]

A new organic-inorganic polyoxoniobate KNa[Co(en) 3 ] 2 [(HNb 6 O 19 )Co(en)] 2 ·30H 2 O ( 1 ) has been successfully synthesized under hydrothermal condition which has been characterized by single-crystal X-ray diffraction, IR spectrum, thermogravimetric analysis and X-ray photoelectron spectroscopy. Compound 1 crystallizes in Ibam space group with a = 19.0985(8) Å, V = 27581(2) Å 3 , Z = 8. X-ray structure analysis reveals that the title polyanion consists of a dimeric alignment constructed from two Lindqvist-type {Nb 6 O 19 } subunits via two {Co III (en)} connectors. [ABSTRACT FROM AUTHOR]

• Compound 1 has been successfully synthesized and characterized. • 1 displays high activity and selectivity for cationic dyes. • The adsorbent 1 exhibits good recyclability and high stability. A new hexatungstate compound, [Ni 2 (L) 3 ] 2 [W 6 O 19 ]·2H 2 O (1) (HL = 2-acetylpyrazine-N(4)-methyl thiosemicarbazone) has been synthesized and characterized by elemental analyses, infrared (IR) spectroscopy, thermal gravimetric analysis (TGA), powder X-ray diffraction (PXRD), single-crystal X-ray diffraction, X-ray photoelectron spectroscopy (XPS) and UV–Vis spectra. A 3D supramolecular structure of 1 is formed by hydrogen bonding, which exhibits a highly selective adsorption for methylene blue (MB), gentian violet (GV) and fuchsin basic (FB) organic dyes with the efficiencies of 99%, 94% and 94%, respectively. Additionally, the adsorption kinetics demonstrates that the MB removal corresponds to the pseudo-second-order model. The recyclability experiments illustrated that 1 could be reused at least five cycles, revealing a potential ability in the disposal to dye wastewater. Image, graphical abstract [ABSTRACT FROM AUTHOR]

A new nano-linear Zn-substituted Strandberg-type phosphomolybdate (H 2 en) 6 {[Zn(H 2 O) 4 ](P 2 Mo 5 O 23)} 3 ·10H 2 O (abbreviated as ZPM) (en = ethanediamine) has been synthesized and structurally characterized by elemental analyses, X-ray powder diffraction (XRPD), IR spectrum, UV–Vis spectroscopy, scanning electron microscope with energy dispersive X-ray (SEM-EDX), thermogravimetric analysis (TGA) and single-crystal X-ray diffraction. Structural analysis shows that [Zn(H 2 O) 4 ]2+ as a linker connected with two adjacent [P 2 Mo 5 O 23 ]6– clusters to form a 1-D structure. Notably, the chemical environment of three adjacent {[Zn(H 2 O) 4 ](P 2 Mo 5 O 23)}4– are different in solid state. To our knowledge, the phenomenon is very rare in polyoxometalates. Moreover, ZPM can catalyze the production of ROS efficiently and can inhibit the proliferation of E. coli by the synergy effect of Zn2+ and [P 2 Mo 5 O 23 ]6– clusters. Image 1 • To our knowledge, ZPM represents the first nano-linear Zn-substituted Strandberg-type phosphomolybdate, in which the three adjacent {[Zn(H2O)4](P2Mo5O23)}4– take different orientations in solid state. • The synthetic method of ZPM will serve as a good example for subsequent synthesis and formation of such transition metal substituted phosphomolybdate clusters. • ZPM can catalyze the production of reactive oxygen species (ROS) in water phase efficiently. • ZPM can inhibit the proliferation of E. coli. [ABSTRACT FROM AUTHOR]