Ternary bismuth oxides Bi_26-xM_xO_40-y(M=Mg,Al,Co and Ni) related to α- Bi₂O₃

Abstract

Reaction of Bi₂O₃ with MgO, NiO, Co₃O₄ and Al₂O₃ gives rise to the corresponding ternary bismuth oxides, Bi₁₈Mg₈O₃₆, Bi₁₈Ni₈O₃₆, Bi₂₀Co₆O₃₉ and Bi₂₄Al₂O₃₉. These oxides have the general formula Bi_26-xM_xO_40-y and exhibit BCC structures related to α - Bi₂O₃. In the first three solids, the metal ions, M, replace bismuth randomly at the octahedral 24r sites (space group 123); in the last case, aluminium ions occupy the tetrahedral 2a sites, the phase being isostructural with Bi₂₄Ge₂O₄₀. Starting from Bi₂O₃ and NiO, orthorhombic Bi₂Ni₂O₅ has also been obtained.