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Updated: Sep 1, 2025

Reverse Microemulsion-mediated Synthesis of Monometallic and Bimetallic Early Transition Metal Carbide and Nitride Nanoparticles
Published on: November 27, 2015
Sr9La2(WO6)4 containing [WO6] octa-hedra
Rayko Simura1, Tomoki Watanabe1, Hisanori Yamane1
1Institute of Multidisciplinary Research for Advanced Materials, Tohoku, University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan.
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 ] polyhedra alternately placed, and a vacancy (□).
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