Effect of Ga substitution on the transport properties of Cu0.5 Mg0.5 Gax Fe2-xO4 spinel ferrites

Transport properties of Cu0.5 Mg0.5 Gax Fe2-xO4 , with (0.0≤x≤0.5) are investigated. The results demonstrate that all of the synthesized materials are spinel structure with cubic unit cell. Moessbauer effect spectra studied at room temperature showed two characteristic ferrimagnetic zeeman sextets for lower concentration of Ga 3+ followed by relaxation phenomenon corresponding to x=0.4 and 0.5. The dependence of Moessbauer effect parameters on Ga3+ concentration and estimation of cation distribution have been discussed. The electrical properties arise from the hopping conduction mechanism. On the basis of the sign of the seebeck coefficient, the ferrites under investigation have been classified as n-type semiconductors and p-type with the increasing of gallium content.