Abstract. Hysteresis loops for Li-Cd ferrites with the general formula Li_0.5-x/2Fe_2.5-x/2Cd_xO₄ (with x = 0,0.1,0.2, ..., 0.7) exhibits good rectangular properties. For the low concentration of Cd²⁺, the squareness of the hysteresis loop is preserved. For the higher concentration of Cd²⁺, hysteresis loop rectangularity is impaired. The magnetic moment for Li-ferrite is 2.19 μ_B and increases with increase in Cd content up to x = 0.2 and then decreases. The measured value of magnetisation of Li-ferrite at 300 K is 2806 gauss. The maximum value of magnetisation about 3640 gauss has been obtained for Cd²⁺ concentration of 20% and then decreases with increase in Cd content. The observed variation in magnetisation is due to changes in the number of tetrahedral and octahedral coordinated Fe³⁺ ions which are coupled ferrimagnetically via a super exchange interaction. The initial increase of magnetisation up to x = 0.2 is explained on the basis of Neel's two sublattice model. For the samples x > 0.2 Y-K angle increases as Cd increases and magnetisation decreases. The Curie temperature (T_c) of the samples in the series were obtained by Loroia technique and it is found that with increase in Cd²⁺ content the Curie temperature decreases. The overall strength of the A-B interaction determines the Curie temperature of the compound. A decrease in the super exchange interaction decreases the Curie temperature.

doi: https://doi.org/10.55318/bgjp.2022.49.3.219

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