Cation distribution, saturation magnetization and magnetocrystalline anisotropy of mixed ferrite NiAlxFe2−xO4 nanoparticles

In a recently proposed model, the magnetocrystalline anisotropy of a mixed ferrite is assumed to be the weighted average of the contributions of the anisotropies of Fe3+ and M2+ ions in A and B sites. In the present work, this model is used to study the cation distribution, saturation magnetization and magnetocrystalline anisotropy of nickel-aluminum ferrite nanoparticles using ferromagnetic resonance data. The experimental results show that the saturation magnetization decreases continuously with aluminum addition, that the magnetocrystalline anisotropy is maximum when 10% of the Fe ions are replaced by Al ions and that replacement of 50% of the Fe ions by Al ions is enough to reduce the saturation magnetization and the magnetocrystalline anisotropy of the mixed ferrite NiAlxFe2-xO4 to almost zero. This is consistent with the findings of other researchers, obtained by different methods.