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Transformation of Tri-Titanium(IV)-Substituted ?-Keggin Polyoxometalate (POM) into Tetra-Titanium(IV)-Substituted POMs : Reaction Products of Titanium(IV) Sulfate with the Dimeric Keggin POM Precursor under Acidic Conditions

ABSTRACT: 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 tri-titanium(IV)-substituted ?-Keggin polyoxometalate (POM) subunits are described. Two novel titanium(IV)-containing ?-Keggin POMs were obtained under different conditions. One product was a dimeric species through two intermolecular Ti-O-Ti bonds of the two tetra-titanium(IV)-substituted ?-Keggin POM subunits, i.e., [[{Ti(H2O)3}2(?-O)](?-PW9Ti2O38)]26- (1). The other product was a monomeric ?-Keggin species containing the tetra-titanium(IV) oxide cluster and two coordinated sulfate ions, i.e., [{Ti4(?-O)3(SO4)2(H2O)8}(?-PW9O34)]3- (2). Molecular structures of 1 and 2 were also discussed based on host (lacunary site)-guest (titanium atom) chemistry.

SUBMITTER: Mouri Y

PROVIDER: S-EPMC5525177 | biostudies-literature | 2010 Jan

REPOSITORIES: biostudies-literature

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