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Abstract: A series of new polyoxometalates based on [Ni6(μ3-OH)3(H2O)6(en)3(B-α-PW9O34)] (en=ethylenediamine) clusters capped by different tripodal alcohol ligands have been hydrothermally synthesized and characterized by IR, TGA and single-crystal X-ray diffraction, respectively. The experimental results indicate that the tripodal alcohol ligands can substitute three hydroxyl groups located on the axial positions of the Ni6 cluster to form new polyoxometalates with different substituted modes. [Copyright &y& Elsevier]

Abstract: An unexpected 3D manganese vanadate (en)Mn2(V2O7) (1) (en=ethylenediamine) has been hydrothermally obtained by H2E2Ge2O3 (E=−CH2CH2COO−) ligands and well-prepared mixture of V–Mn-amine and characterized by IR spectroscopy, elemental analysis, thermal stability and powder X-ray diffraction. Single-crystal X-ray diffraction analysis reveals that the structure is a novel pillared-layer, in which MnO5N octahedra are corner-linked to form an infinite sheet with 4-membered rings (MRs) and further condensed to the 3D framework. The most prominent feature of 1 is the connection between the sheets via double bridges, namely, inorganic V2O7 dimeric units and organic en molecules. It is noteworthy that inorganic and organic double bridges between sheets have not been seen in manganese vanadates. [Copyright &y& Elsevier]

A new hybrid germanium vanadate (2,2′-bpy)2(VVO2)2(H2GeO4) · 6H2O 1 (2,2′-bpy=2,2′-bipyridine) was synthesized by hydrothermal method and structurally characterized by single-crystal X-ray diffraction, thermogravimetric analysis (TGA), IR, XRD and elemental analyses. Crystal data for 1: monoclinic, C2/c, a=16.6937(9) Å, b=11.3501(6) Å, c=17.4774(9) Å, β=118.19(2)°, V=2918.7(3) Å3, Z=4. Compound 1 is composed of the first germanium vanadate skeleton covalently attached to 2,2′-bpy ligands. [Copyright &y& Elsevier]

Two new inorganic frameworks HLa(H 2 O)5[La(H 2 O)6]2[La(H 2 O)2(GeW11O39)]2·7H 2 O ( 1 ) and HK(H 2 O)La 3 (H 2 O) 15 [La(H 2 O) 3 (GeW 11 O 39 )] 2 ·38H 2 O ( 2 ) based on 1:1 type lanthanide-substituted polyoxometalates (LSPs) have been synthesized under hydrothermal reactions. Compounds 1 and 2 are characterized by single-crystal X-ray diffraction analysis, thermogravimetry analysis, infrared spectroscopy and X-ray powder diffraction analysis. Interestingly, Compounds 1 and 2 can be selectively obtained by simply controlling the reaction temperatures under similar conditions. Both 1 and 2 are three-dimensional structures built from lanthanide-substituted polyoxoanions [La(H 2 O) n (GeW 11 O 39 )] 5 − building blocks. Furthermore, the ion-conducting properties of 1 and 2 were investigated. [ABSTRACT FROM AUTHOR]

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]

A neutral zincophosphate monomer [Zn(2,2′-bipy)]2(H2PO4)4 has been synthesized under hydrothermal condition in the presence of 2,2′-bipyridine ligands. The structure consists of a 4-membered ring formed by vertex-sharing ZnO3N2 square pyramids and H2PO4 tetrahedra, with two H2PO4 groups hanging from the zinc atoms. This compound exhibits intense photoluminescence upon photoexcitation at 388 nm. [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]

Polyoxoniobate [GeNb 18 O 54 ] 14 − and polyniobotungstate [Nb 3 W 3 O 19 ] 5 − are firstly found to co-crystallize at the same crystal to form a rare organic–inorganic hybrid polyoxometalate H[Cu(en) 2 (H 2 O)] 8 [Cu(en) 2 (H 2 O) 2 ] 2 {K 4 [Cu(en) 2 ] 2 [Cu(en) 2 (GeNb 18 O 54 )] 2 }[Nb 3 W 3 O 19 ]·32H 2 O ( 1 ). Interestingly, in 1 , the crescent-shaped polyoxoanions [GeNb 18 O 54 ] 14 − can form dimeric secondary building units (SBUs) {[GeNb 18 O 54 ] 2 [K 2 (H 2 O) 5 ] 2 } via the linkage of K + cations. These dimeric SBUs can be further bridged by copper complexes to generate 1D infinite double strand chains with completely different isolated polyoxoanions [Nb 3 W 3 O 19 ] 5 − filling the gaps between chains. [ABSTRACT FROM AUTHOR]

A unique {SiNb 18 O 54 }-based framework was prepared and characterized. The compound is very stable, and can selectively absorbs crystal violet from aqueous solution. Additionally, the proton-conduction property of the compound was also studied. • A novel polyoxoniobate framework based on crescent-like {SiNb 18 O 54 } clusters has been made. • The compound shows good thermal/chemical stabilities under various conditions. • The compound can selectively absorb crystal violet from aqueous solution. • The proton-conduction property of the compound was studied. A novel inorganic-organic hybrid polyoxoniobate framework based on crescent-like {SiNb 18 O 54 } building blocks and [Cu(en)]2+/K+ (en = ethylenediamine) linkers has been successfully made under hydrothermal condition. The compound is very stable under various conditions, and can selectively absorb crystal violet from aqueous solution. Additionally, the proton-conduction property of the compound was also studied. [ABSTRACT FROM AUTHOR]

A series of novel 4s–4f heterometallic cluster substituted polyoxometalates (POMs) with formula of H 9 Na 12 K 2 [K 3 Ln 4 (NO 3) 2 (GeW 10 O 37) 2 (Ge 2 W 18 O 66)]·34H 2 O (1-Ln) (Ln = Dy, Ho, Er) have been hydrothermally made by adopting a trilacunary [A-α-GeW 9 O 34 ]10− as a precursor. 1-Ln represent the first examples of metal-substituted POM clusters based on mixed POM fragments including dilacunary [α-GeW 10 O 37 ]10− and multilacunary open Well-Dawson [Ge 2 W 18 O 66 ]16− fragments. • Novel 4s–4f heterometallic substituted POMs have been prepared and characterized. • The compounds contain mixed Keggin/ open Well-Dawson POM fragments. • The Luminescent properties of these compounds were systematically studied. • The work enriches the diversity of heterometallic metal cluster substituted POMs. • This work provides a new route for making new POMs based on mixed POM units. By adopting a trilacunary [A-α-GeW 9 O 34 ]10− as a precursor under hydrothermal conditions, a series of novel 4s–4f cluster substituted polyoxometalates (POMs) containing two types of in situ generated lacunary POM fragments have been made. These compounds were characterized by single-crystal X-ray diffractions, powder X-ray diffractions, infrared spectroscopy, thermogravimetric analyses, respectively. Structural analyses indicate that these compounds constructed from a seven-nuclearity K-O-Ln (Ln = Dy, Ho, Er) heterometallic cluster stabilized by mixed dilacunary Keggin [α-GeW 10 O 37 ]10−/multilacunary open Wells-Dawson [Ge 2 W 18 O 66 ]16− fragments. Furthermore, the solid luminescent properties of the compounds at room temperature were studied. [ABSTRACT FROM AUTHOR]