X-ray study of cation distribution in NiMn1−xFe2−xO4 ferrites

The spinel ferrite system NiMnxFe2−xO4, with x=0, 0.2, 0.4, 0.6, 0.8 and 1, was prepared by the standard double sintering ceramic method. The cation distribution has been calculated analytically for the first time using X-ray diffraction combined with computer technology. The results show, with increasing manganese ion substitution, that both Ni2+ and Mn3+ ions predominately occupy the octahedral sites. This is consistent with their preference for large octahedral site energy. The concentration of Mn3+ ions in octahedral sites increases while that of Fe3+ ions decreases linearly.