“…It indicates a progressive rise in ac on increasing temperature, which signifies electrical conduction in the material as a thermally activated process. This pattern of variation obeys a relation [ ac = o exp(−E a /kT)], where o is the pre-exponential factor, E a is the activation energy, k is the Boltzmann constant and T is the absolute temperature [41]. It is observed that the value of E a decreases with rise in frequency, which is due to the enhancement of electronic jumps between localized states.…”