Structural intergrowth phenomena in the Sb WO3 system

The Sb x WO 3 system has been examined by powder X-ray diffraction and high-resolution electron microscopy. In the composition range Sb 0.01 WO 3 and Sb 0.07 WO 3 , a series of perovskite-related tungsten bronzes form. In the composition range approximately Sb 0.12 WO 3 to Sb 0.20 WO 3 , a series of structures were found which can be regarded as more or less ordered intergrowths of lamellae of the WO 3 and hexagonal tungsten bronze structures. The WO 3 slabs are n octahedra thick and a knowledge of the value of n allows the chemical composition of the phases, x = 1 (2n + 1) , to be calculated. No n values below 2 were observed and for x > 0.15, fairly large regions with the ordered n = 2 structure were found.