Conductivity and cation distribution in CuxMg1−xFe2O4 system

The electrical conductivity and magnetization of Cu_xMg_1{xFe₂O₄ are measured. The electrical conductivity obeys the exponential behaviour characteristic of semiconducting materials. The activation energy in the paramagnetic region is found to be greater than that in the ferrimagnetic region. This is attributed to the change in magnetic ordering. It is observed that the plots of logQ vs 10³/T exhibit a linear relationship throughout the temperature region studied (room temperature to 1000 K). The slope of the plot changes at a particular temperature recognized as Curie temperature. These temperatures agree well with the experimentally obtained Curie temperatures using Laroia technique. Hopping of polarons mechanism is used to explain the conduction behaviour in ferrites. The magnetic moment (n_B) is calculated from the magnetization studies carried out at 78 K. The cation distribution is suggested on the basis of these magnetization data.The authors are thankful to Prof. R. N. Patil for encouragement.