MAGNETIZATION AND STRUCTURAL STUDIES OF CUXMG1-XFE2O4 FERRITE SYSTEM

The crystal structure and magnetization data for slow cooled copper magnesium ferrites with the general formula CuxMg1-xFe2O4 with x = 0.2, 0.4, 0.6, 0.8 and 1 are presented. The ferrites with x < 0.6 show a cubic phase with almost identical lattice parameters. For x > 0.7 ferrites show a tetragonal phase with c/a ratio ranging from 1.03 to 1.07. Pure copper ferrite is tetragonal in nature with c/a ratio equal to 1.05. The experimental values M(s) and n(B) are found to increase with increasing content of magnesium in ferrites until they become maximum for x = 0.6 and thereafter decrease, similar to the behaviour of copper ferrites containing varying amounts of Zn. The variation is explained on the basis of cation distribution, tetragonality of the ferrites and the Neel two sub-lattice model.