Mössbauer study of substituted rare-earth ortho-ferrites

The magnetically non-equivalent states of Fe and Sn atoms in rare-earth ortho-ferrites substituted by tin ions (R1 – xCaxFe1–xSnxO3) were investigated using the Mössbauer effect. It is shown that all tin ions are distributed randomly over the octahedral sites of the orthoferrite lattice. It is revealed that the main contribution to the effective magnetic field at the tin nuclei is defined by magnetic ions of the nearest coordination sphere (81%), where each nearest magnetic ion gives an equal and independent contribution to the field. The sign of the magnetic field for all other coordination spheres coincides with the sign of the nearest environment field and the value of the field is equal to 19%.