Synthesis of new layered-type and new mixed-layered-type bismuth compounds

Four new compounds, PbBi₂TiTaO₈F, PbBi₂TiNbO₈F, Bi₅Ti₂WO₁₄F, and Bi₇Ti₅O₂₀F, were prepared and identified by X-ray diffraction analysis. Two of them are new members of a family called layered bismuth compounds. The other two are new members of a family called mixed-layered bismuth compounds. Thermal properties of the new compounds were studied. Moreover, the possibility of the existence of other new members belonging to the family called mixed-layered bismuth compounds is discussed.