A Theoretical Approach: Effects of Mn Substitution in Cobalt Ferrite

Abstract

This paper reports on the effect of Mn substitution in cobalt ferrite to explore the probable correlation among the structural, magnetic, and magneto-mechanical properties by a theoretical approach. Three compositions of Mn doped Cobalt ferrites at different Mn concentration (x) = 0.125, 0.25, 0.375, 0.5 have been undertaken for their analytical study to understand the correlation among the aforesaid properties. In this approach, an empirical equation has been formulated based on idealistic cation distribution in tetrahedral and octahedral sites of cobalt ferrite at room temperature. The hopping lengths and bond lengths have also been estimated using the corresponding Stanley’s equations in idealistic condition. The estimated lattice constant is found to decrease and effective magnetic moment μferri to increase with the Mn content, substituted for Co in the octahedral site due to increased A-B interactions. This increasing effect of Mn content in cobalt ferrite may be significant to the tunability of the Curie temperature, TC and may have an influence on superparamagnetism (SPM). On the other hand, the compositions where Mn substituted for Fe may increase the porosity due to their increased bond lengths with Mn content and thus may optimize them for applications in the environmental (gas) sensors. However, the analysis of the predicted effects of Mn and correlation thereon is completely based on the theoretical approach and thereby need experimental verification to confirm and supplement them.