Study of substitution limit, structural, bulk magnetic and electrical properties of Ca2+ substituted magnesium ferrite

Abstract The percentage substitution of large cation like Ca 2+ for Mg 2+ in MgFe 2 O 4 without altering the cubic symmetry and its effect on structural, bulk magnetic and electrical properties have been investigated for Mg 1− x Ca x Fe 2 O 4 ( x =0.0–0.35) spinel ferrite system by means of X-ray diffraction (XRD), magnetization, ac susceptibility and dc resistivity measurements. It is found that a maximum of 23% of Ca 2+ can be substituted for Mg 2+ . The variation of magneton number with x can be explained on the basis of Neel’s collinear spin model. The Neel temperature determined through ac susceptibility and dc resistivity measurements agree with those calculated theoretically. The variation of electrical resistivity go hand in hand with the variation of the activation energy with the Ca-content.