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A family of penta‐rare‐earth incorporated tetravacant Dawson selenotungstates [H2N(CH3)2]10H3[SeO4RE5(H2O)7(Se2W14O52)2] ⋅ 40H2O [RE=Ho3+ (1), Er3+ (2), Tm3+ (3), Tb3+ (4)] were synthesized. It should be noted that a penta‐RE [SeO4RE5(H2O)7]11+ central core connecting two tetra‐vacant Dawson‐type [Se2W14O52]12− subunits generates a dimeric assembly of [SeO4RE5 (H2O)7(Se2W14O52)2]13− in the structures of 1–4. Meanwhile, a class of Ho3+/Tm3+ co‐doped derivatives based on 1 with a Ho3+/Tm3+ molar ratio of 0.75:0.25–0.25:0.75 were also prepared and characterized by energy‐dispersive spectroscopy (EDS) analyses. Moreover, their luminescence properties were systematically investigated, which indicate that Tm3+ ions can sensitize the emission of Ho3+ ions in the visible region and prolong the fluorescence lifetime of Ho3+ ions to some extent. Energy transfer from Tm3+ ions to Ho3+ ions was probed by time‐resolved emission spectroscopy (TRES), and the CIE 1931 diagram has been applied to evaluate all possible luminescence colors. [ABSTRACT FROM AUTHOR]

A novel 3-connected SrSi2-type 3D chiral framework constructed from hexa-NiII-cluster-substituted polyoxometalate (POM) units [Ni(enMe)2]3[WO4]3[Ni6(enMe)3(OH)3PW9O34]2⋅9H2O ( 1) (enMe=1,2-diaminopropane) has been made from a hydrothermal synthetic method. This POM represents the first 3D framework based on {Ni6PW9} units and {WO4} connectors. [ABSTRACT FROM AUTHOR]

Abstract: Three new sandwich-type polyoxotungstates (POTs) decorated by nickel-2,2′-bpy complexes [{Ni(2,2′-bpy)2(H2O)}2{Ni(2,2′-bpy)}2 {Ni4(H2O)2(B-α-XW9O34)2}]n− (X=PV, n=4 for 1; X=AsV, n=4 for 2; X=GeIV, n=4 for 3) (2,2′-bpy=2,2′-bipyridine) were successfully synthesized under hydrothermal conditions and structurally characterized by elemental analyses, IR spectroscopy, single-crystal X-ray diffraction, and magnetic properties. Single-crystal structural analyses indicate that 1 and 2 are isostructural and both crystallize in the monoclinic space group C2/c, whereas 3 belongs to the triclinic space group . To our knowledge, 1, 2 and 3 represent rare examples of the organic–inorganic hybrid sandwich-type polyoxometalates functionalized by multiple nickel-aromatic amine complexes. Magnetic measurements of 1 exhibit the presence of ferromagnetic interactions within the rhombic tetranuclear-NiII cluster. [Copyright &y& Elsevier]

Abstract: A novel di-copperII-complex substituted monovacant Keggin polyoxotungstate [Cu(2,2′-bpy)(H2O)][H2PW11O39Cu2(2,2′-bpy)2(H2O)(OH)]·1.5H2O (1) (2,2′-bpy=2,2′-bipyridine) with a 1D polymeric chain has been hydrothermally synthesized and structurally characterized. To our knowledge, 1 is the rare magnetic di-transition metal-complex substituted monovacant Keggin polyoxotungstate with a unique 1D dual-bridging chain structure. Its magnetic behavior has been quantitatively analyzed by the Bleaney–Bowers equation, indicating the presence of weak antiferromagnetic interactions within dinuclear CuII centers. [Copyright &y& Elsevier]

Abstract: Combination of in-situ generated monocopperII-substituted Keggin polyoxoanions with copperII–organoamine complexes under hydrothermal conditions results in seven inorganic–organic composite polyoxotungstates [Cu(en)2(H2O)]2{[Cu(en)2][α-PCuW11O39Cl]}·3H2O (1), {[Cu(en)2(H2O)][Cu(en)2]2[α-PCuW11O39Cl]}·6H2O (2), {[Cu(en)2(H2O)]2[Cu(en)2][α-XCuW11O39]}·5H2O (3/4, X=SiIV/GeIV), {[Cu(deta)(H2O)2]2[Cu(deta)(H2O)][α-XCuW11O39]}·5H2O (5/6, X=GeIV/SiIV) and [Cu(dap)2]2{[Cu(dap)2]2[Cu(dap)2][α-PCuW11O39]2} (7) (en=ethylenediamine, dap=1,2-diaminopropane and deta=diethylenetriamine). 1 is an isolated structure whereas 2 is a 1-D chain structure, but both contain [α-PCuW11O39Cl]6− polyoxoanions. 3–6 contain the 1-D linear chains made up of [α-XCuW11O39]6− polyoxoanions in the pattern of –A–A–A– (A=[α-XCuW11O39]6−), while 7 demonstrates the first 1-D zigzag chain constructed from [α-PCuW11O39]2 10− polyoxoanions via [Cu(en)2]2+ bridges in the pattern of –A–B–A–B– (A=[α-PCuW11O39]2 10−, B=[Cu(en)2]2+). The successful syntheses of 1–7 can provide some experimental evidences that di-/tri-/hexa-vacant polyoxoanions can be transformed into mono-vacant Keggin polyoxoanions under hydrothermal conditions. [Copyright &y& Elsevier]

The reaction of the mono-lacunary silicotungstate ligand α-K8SiW11O39 · 13H2O with praseodymiumIII cation results in a new Keggin-type derivative K3[(Pr(H2O)4SiW11O39)(NaPr2(H2O)12)(Pr(H2O)4SiW11O39)] · 13.5H2O (1), whose polyanion consists of two crystallographically distinct [Pr(H2O)4SiW11O39]5- building block units and one [NaPr2(H2O)12]7+ subunit, which are connected by alternating praseodymium and sodium centers via the terminal and bridging oxygen atoms from the precursor [α-SiW11O39]8- to construct a 1D infinitely chainlike structure. [Copyright &y& Elsevier]

Abstract: A novel polyoxotungstate cluster (H2en)2.5H9[Fe6Ge3W24O94(H2O)2]·14H2O (1) (en=ethylenediamine) has been hydrothermally synthesized and structurally characterized by IR, TGA and single-crystal X-ray diffraction. The polyoxoanion skeleton of 1 is composed of two tri-FeIII substituted B-α-(Fe3GeW9O40) Keggin units connected by an unique hexavacant GeW6O26 Keggin fragment, leading to the first Fe(III)-containing banana-shaped tungstogermanate. Magnetic measurements of 1 reveal that the exchange interactions within the trimetal clusters are antiferromagnetic. [Copyright &y& Elsevier]

POM framework In their Communication on page 2315 ff. J. ‐ W. Zhao, G ‐ Y. Yang et al. report an unprecedented SrSi2 ‐ type 3D chiral framework based on Ni6PW9 SBUs and tetrahedral WO42− linkers under hydrothermal conditions. Their work provides an effective and feasible strategy in constructing POM ‐ based frameworks by linking transition ‐ metal ‐ substituted POM clusters using inorganic oxometal anionic linkers. [ABSTRACT FROM AUTHOR]

Abstract: An unprecedented Keggin-type tungstogermanate dimer bearing dinuclear copper-organic coordination ions {H8[Cu(phen)(μ2-CH3COO)2Cu(phen)(H2O)]2[Ge2W23CuO80]}·24H2O has been synthesized and characterized by IR, UV, ICP analyses, ESR spectra, element analysis, TG and single crystal X-ray diffraction analysis. The compound is built up from a dimeric heteropolyanion constituted by two corner-shared Keggin-type building subunits and two dinuclear copper-organic coordination cations [Cu(phen)(μ2-CH3COO)2Cu(phen)(H2O)]2+, each of which consists two square pyramidal copper-phen ions bridged by two μ2-acetate ligands. [Copyright &y& Elsevier]

This review summarizes the state-of-the-art research progresses on polyoxoniobates made in the past decade with an emphasis on abundant structure characteristics and their related catalytic properties. [Display omitted] • The advances of polyoxoniobate-based materials. • Structural features and catalytic applications of polyoxoniobate-based materials. • Catalytic properties involving photocatalysis, base catalysis and oxidation catalysis. • The challenges and outlook in polyoxoniobate-based materials. Polyoxoniobates (PONbs), a remarkable category of metal-oxo cluster materials, have attracted significant attention, owing to their structural diversity and high nucleophilicity. Because of their special electronic structures, adjustable energy bands, and high stabilities, PONb-based functional materials can be environmentally friendly catalyst candidates. Herein, we systematically summarise typical PONbs reported in the past several decades, which can be generally classified into five categories: isopolyoxoniobates, heteropolyoxoniobates, transition-metal-containing PONbs, rare-earth-containing PONbs, and transition-metal-rare-earth-containing PONbs. Their compositions, structural diversities, and catalytic properties and applications have been comprehensively discussed. This review provides some instructive guidance for the further discovery and development of efficient and robust PONb-based functional materials in the future. [ABSTRACT FROM AUTHOR]

Abstract: A novel 2-D hexa-CuII substituted sandwich-type polyoxotungstate [Cu(H2O)4][Cu(dien)(H2O)2]2[Cu(dien)(H2O)]2[Cu6(en)2(H2O)2(B-α-HGeW9O34)2][Cu6(Hdien)2(H2O)2(B-α-HGeW9O34)2]·24 H2O (1, en=ethylenediamine, dien=diethylenetriamine) has been hydrothermally synthesized and structurally characterized by elemental analyses, IR spectroscopy, powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA) and single-crystal X-ray diffraction. 1 represents the first 2-D inorganic–organic hybrid sandwich-type germanotungstate constructed by two kinds of hexa-CuII substituted sandwich-type POM hybrid units accompanying the mixed organoamine components in the structure. The TGA curve of 1 displays two continuous weight loss stages. [Copyright &y& Elsevier]