1. Niobium uptake by {P2W12} polyoxoanion with [NbO(C2O4)2(H2O)2]− as Nb source
- Author
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Eugeniy M. Glebov, Taisiya S. Sukhikh, Vadim V. Yanshole, Alexandra A. Shmakova, Dmitri V. Stass, Victoria V. Volchek, Maxim N. Sokolov, Eugeniy Yu. Filatov, and Pavel A. Abramov
- Subjects
Aqueous solution ,010405 organic chemistry ,Niobium ,chemistry.chemical_element ,010402 general chemistry ,01 natural sciences ,0104 chemical sciences ,law.invention ,Inorganic Chemistry ,Crystallography ,Diffuse reflectance spectra ,chemistry ,law ,Materials Chemistry ,Physical and Theoretical Chemistry ,Crystallization ,Thin film ,Powder diffraction ,Natural bond orbital - Abstract
Reaction of (NH4)[NbO(C2O4)2(H2O)2]·3H2O with K12[H2P2W12O48]∙24H2O in aqueous solution at pH 1.7 leads to the formation of mixed Nb/W species based on [(P2M18O60)2(µ-O)2]n− (M is a Nb/W mixture, when Nb ratio ranges from 6 to 8 and charge differs from 14- to 16- correspondingly) archetype. Direct crystallization from the reaction media results in colorless crystals with the composition formulated as K9(NH4)5[cis-(P2W15Nb3O61)2]·48H2O (1). Crystallization in the presence of (NMe2H2)Cl yields two phases (2a and 2b), containing the same [trans-(P2W14.7Nb3.3O61)2]14.6− anions but different cation/H2O compositions. Both phases are present in a mixture with bulk composition corresponding to (NMe2H2)14.6[P2W14.7Nb3.3O61]2·28H2O (2). The solution behavior of 1 and 2 was studied with HR-ESI-MS and HPLC-ICP-AES. During XRPD study of 2 we found blue coloration of the thin film of the complex. This effect has only surface nature and was studied by diffuse reflectance spectra.
- Published
- 2020