Structure Analysis of the 6H–Ba(Ti, Fe3+, Fe4+)O3−δSolid Solution

摘要: Abstract The 6H form of BaTiO 3 forms an extensive solid solution with barium iron oxide, having the general formula BaTi 1− x − y Fe 3+ 4+ O 3− /2 , where /Fe ratio depends on reaction temperature and gas atmosphere. Two series solutions predominantly in or were prepared by quenching from high temperatures air slow cooling to 200°C oxygen, respectively. structural variations both obtained Rietveld refinements powder X-ray diffraction data. For ∼0, progressive substitution Ti is accompanied formation O(1) oxygen vacancies h -BaO layers that separate pairs occupied face-shared octahedra. maximum vacancy concentration occurs at =0.67, which corresponds a composition Ba□O 2 (□=vacancy) -stacked layers. Solid members >0.67 unstable relative other polymorphs. Further incorporation into structure i.e., increasing . observed phases are explained terms Ba Fe, atom packing changes interatomic interactions between metal atoms as removed site.