Reaction products of titanium(IV) sulfate in HCl-acidic aqueous solution with the dimeric species linked through three intermolecular Ti-O-Ti bonds of the two trititanium(IV)-substituted α-Keggin polyoxometalate (POM) subunits are described. Two novel titanium(IV)-containing α-Keggin POMs were obtained under different conditions. One product was a dimeric species through two intermolecular Ti-O...

A novel intercluster compound, [{{Au(PPh(3))}(4)(μ(4)-O)}{{Au(PPh(3))}(3)(μ(3)-O)}][α-PW(12)O(40)]·EtOH (1) constructed between a heptakis{triphenylphosphinegold(i)}dioxonium cation and an α-Keggin polyoxometalate (POM) is synthesized and unequivocally characterized by elemental analysis, TG/DTA, FTIR, X-ray crystallography, solid-state CPMAS (31)P NMR and solution ((1)H, (31)P{(1)H}) NMR. The ...

Nine new Sb-bicapped α-Keggin-type heteropolyoxoniobates (HPNb) were synthesized under hydrothermal conditions. Among them, the As-centered HPNb was never reported before, and the two dimer compounds are the biggest isolated HPNbs at present.

Caps in α-Keggin-type polyoxometalates [PM2Nb12O40](9-) (M: Nb[double bond, length as m-dash]O or V[double bond, length as m-dash]O) can be removed in basic condition to produce uncapped [PNb12O40](15-). Transmetalation or capping occurs from the reaction of [PNb14O42](9-) or [PNb12O40](15-) with either Sb2O3 or V2O5 to form [PSb2Nb12O40](9-) or [PV2Nb12O42](9-), respectively.

Fluorescent microtubes based on α-Keggin tungstosilicate and fluorescein (SiW(12)-F) have been obtained by using a simple method, which present tunable photoluminescence from sky blue to green to red by variation of excitation light. The SiW(12) component can inhibit photobleaching of fluorescein.

New organophosphonate derivatives of monovacant Keggin-type polyoxotungstates that contain naphthyl groups have been synthesized and characterized in both solid state and solution. Single-crystal structural analysis shows that two phosphonate groups occupy the vacant position of the lacunary cluster unit in the isostructural compounds [N(C4H9)4]3[H(POC11H9)2(α-HBW11O39)] (TBA-1) and [N(C4H9)4]3...

The synthesis and molecular structure of a monomeric diplatinum(II) complex composed of mono-lacunary α-Keggin polyoxometalate is described. The polyoxometalate, Cs(3)[α-PW(11)O(39){cis-Pt(NH(3))(2)}(2)]·8H(2)O (Cs-1), afforded by a stoichiometric reaction of mono-lacunary Keggin polyoxotungstate with cis-diamminedichloroplatinum(ii) in water, followed by crystallization from water, was obtaine...

The interaction between the plenary Keggin H3PW12O40, lacunary Keggin K7PW11O39 and the Eu(III)-substituted Keggin K4EuPW11O39 (Eu-Keggin) type polyoxometalates (POMs), and the proteins human and bovine serum albumin (HSA and BSA) was studied using steady state and time-resolved Eu(III) luminescence and tryptophan (Trp) fluorescence spectroscopy. The excitation spectrum of the Eu-Keggin POM is ...

We report the formation of two polyoxotungstates of the general formula [M6(PW6O26)(α-P2W15O56)2(H2O)2](23-) (M = Co(II) or Mn(II)), which contain {PW6} fragments generated from the [P2W15O56](12-) precursor, which demonstrates for the first time the transformation of a Dawson lacunae into a Keggin lacunary building block. Solution analysis of the clusters has been conducted via electrospray io...

Herein, we report for the first time polyoxometalate (POM)-based single-molecule magnets with mononuclear transition metal cores. The mononuclear Fe(III)-, Co(II)-, and Mn(III)-containing POMs have successfully been synthesized from a trivacant lacunary Keggin-type silicotungstate precursor TBA4H6[A-α-SiW9O34]·2H2O (TBA = tetra-n-butylammonium), and the highly distorted octahedral geometries of...