Ba3[Sn(OH)6][SeO4]2·3H2O, a hydrated 1:2 double salt of barium hexa-hydroxidostannate(IV) and barium selenate(VI).

Abstract

Single crystals of tribarium hexa-hydroxidostannate(IV) bis-[selenate(VI)] trihydrate, Ba3H12O17Se2Sn or Ba3[Sn(OH)6][SeO4]2·3H2O, prepared from solid BaSnO3 and aqueous Na2[SeO4] solutions have hexa-gonal (P63) symmetry. The structure consists of four different primary building units: a hexa-hydroxidostannate(IV) ion, two different selenate(VI) ions, all three of point group symmetry C 3, and a mono-capped {BaO9}-square anti-prism of point group symmetry C 1. The secondary building units result from three of the barium coordination polyhedra linked together via common edges. While one of the two tetra-hedral voids formed from these trimeric units is filled by one bidentate, chelating μ2-selenate ion, the other one remains unoccupied as the corresponding second selenate ion only acts as a monodentate, μ1-ligand. SBUs are completed by hexa-hydroxidostannate(IV) ions sharing adjacent edges on the uncapped faces of the three, mono-capped square anti-prisms. These SBUs are arranged into layers via common edges on the uncapped, square faces of the {BaO9} coordination polyhedra in a way that the hexa-hydroxidostannate(IV) ions act as linkage between two neighboring layers.