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The sodium and cesium salts of two new heteropolyoxometalate complexes [{Ln3O3(OH2)2}(PW9O34)2]15- were synthesized and studied using spectroscopy and cyclic voltammetry. The stoichiometry of the trilacunary Keggin 9-tungstophosphate reaction with Ln(III) ions was detd. with the aid of conductometric titrns. of aq. solns. Ion-exchange as well as ES-MS expts. provided evidence for covalent, inner-sphere bonding of lanthanide cations to the trilacunary
Read moreMonolacunary Wells-Dawson 16-tungsto-molybdo-phosphate [P2MoW16O61]10- reacts with [Ti(H2O)6]4+ in aqueous solution to give the [Ti(H2O)P2MoW16O61]6- complex, isolated as the potassium salt. Optimal synthesis conditions were established by spectrophotometric and conductometric studies. The molecular formula of the complex was determined by elemental analysis, thermogravimetric analysis and basicity titration. The Ti(IV) complex was further characterized
Read moreTwo tris(oxouranium)-substitued Keggin and Dawson sandwich-type tungstophosphate heteropolyanions Na12[(UO)3(H2O)6(PW9O34)2]·21 H2O (1) and Na18[(UO)3(H2O)6(P2W15O56)2]·27 H2O (2) have been prepared by reaction of uranium sulphate with [PW9O34]9- and [P2W15O56]12-, respectively, in aqueous media at 4.7 pH. The products were characterized by elemental and thermal analyses, IR, UV-Vis spectroscopy and magnetical susceptibility. The results of these
Read moreMono- or bis(organoelement)-substituted Keggin molybdotungstophosphates K4[C6H5SnPMo2W9O39]·14H2O, K4[C4H9SnPMo2W9O39]·14H2O, K3[(C2H3Si)2 PMo2W9O40]·17H2O, tris(organoelement)-substituted Keggin tungstophosphates and tungstoarsenates Cs12[(C4H9SnOH)3(PW9O34)2]·19H2O, K11H[(C2H3SiOH)3(PW9O34)2] ·14H2O, Cs12[(C4H9SnOH)3(AsW9O33)2]·43H2O, Cs12[(C2H3SiOH)3(AsW9O33)2] ·12H2O, and mono- or bis(organoelement)-substituted pseudo-Keggin tungstoantimonates
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