Conversion electron Mössbauer study of the (Bi, Y)₃Fe₅O₁₂ single-crystal films

Conversion electron Mössbauer effect measurements have been performed on the (111)-oriented (Bi, Y)₃Fe₅O₁₂ single-crystal films at room temperature. The dependence of the isomer shift (δ) and magnetic hyperfine field (H_hf) of the 24d site on Bi concentration shows that the degree of covalence of the bond decreases with Bi concentration and the change of H_hf is not directly proportional to that of the 24 d sublattice magnetization. The values of δ and H_hf of the 16a site are kept at almost the same value. The magnetic structure of the (Bi, Y)₃Fe₅O₁₂ films is collinear ferrimagnetic and the direction of the net magnetization of the Bi₃Fe₅O₁₂ film is along the <110> axis.