Valence compensated perovskite oxide system Ca1-xLaxTi1-xCrxO3 - Part III - Impedance spectroscopy

Electrical behaviour of the compositions with x less than or equal to 0.50 in the Ca1-xLaxTi1-xCrxO3 system has been studied by employing complex plan e impedance and spectroscopic analysis in the temperature range 100 K-550 K . These studies have revealed the contribution of three processes to the to tal electrical conductivity of these samples. An equivalent electrical circ uit model, which contains series arrangement of three paralle RC elements, is proposed to represent the electrical characteristics of these materials. Out of these three, two processes correspond to the activated hopping proc esses within the bulk while the third process corresponds to the barrier la yer formation in these ceramics. Immittance spectroscopic analysis shows th at conduction occurs through localized as well as long range movement of ch arge carriers. (C) 2001 Kluwer Academic Publishers.