Polytypism and oxo-tungstate polyhedra polymerization in novel complex uranyl tungstates
Andrey N Seliverstov1, Evgeny V Suleimanov, Evgeny V Chuprunov
1Lobachevsky State University of Nizhny Novgorod, Gagarin Av. 23b, 603950 Nizhny Novgorod, Russia.
Abstract:
Three new uranyl tungstates, α-, β-Cs(2)[(UO(2))(2)(W(2)O(9))], and Rb(6)[(UO(2))(7)(WO(5))(2)(W(3)O(13))O(2)], have been obtained by high temperature solid state reactions. All three compounds display novel structure topologies: α- and β-Cs(2)[(UO(2))(2)(W(2)O(9))] are based upon layers with a new topology that can be related to the uranophane topology; Rb(6)[(UO(2))(7)(WO(5))(2)(W(3)O(13))O(2)] is a rare example of a non-molecular inorganic phase with layers containing oxo-tungstate trimers. The structural relationship between α- and β-Cs(2)[(UO(2))(2)(W(2)O(9))] can be assigned to polytypism.
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