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Sr₉La₂(WO₆)₄ containing [WO₆] octa-hedra.

ABSTRACT: A polycrystalline sample of Sr₉La₂(WO₆)₄, nona-strontium dilanthanum tetra-kis-[orthotungstate(VI)], was prepared by heating a compacted powder mixture of SrCO₃, WO₃, and La₂O₃ with an Sr:La:W molar ratio of 9:2:4 at 1473 K. X-ray crystal structure analysis was performed for a Sr₉La₂(WO₆)₄ single-crystal grain grown by reheating the sample at 1673 K. Sr₉La₂(WO₆)₄ crystallizes with four formula units in the tetra-gonal space group I4₁/a and is isotypic with Sr₁₁(ReO₆)₄. Two W sites with site symmetries of are located at the center of isolated [WO₆] octa-hedra, and four mixed (Sr/La) sites are surrounded by eight to twelve O atoms of the [WO₆] octa-hedra. The structure of Sr₉La₂(WO₆)₄ can be described on the basis of the double-perovskite structure with [WO₆] and [(Sr/La)O _x ] polyhedra alternately placed, and a vacancy (□).

SUBMITTER: Simura R

PROVIDER: S-EPMC9361373 | biostudies-literature | 2022 Aug

REPOSITORIES: biostudies-literature

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Sr9La2(WO6)4 containing [WO6] octa-hedra.

Simura Rayko R Watanabe Tomoki T Yamane Hisanori H

Acta crystallographica. Section E, Crystallographic communications 20220705 Pt 8

A polycrystalline sample of Sr9La2(WO6)4, nona-strontium dilanthanum tetra-kis-[orthotungstate(VI)], was prepared by heating a compacted powder mixture of SrCO3, WO3, and La2O3 with an Sr:La:W molar ratio of 9:2:4 at 1473 K. X-ray crystal structure analysis was performed for a Sr9La2(WO6)4 single-crystal grain grown by reheating the sample at 1673 K. Sr9L ...[more]

PMID: 35974823

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