Electrical properties of La0.67Sr0.16Ca0.17MnO3 perovskite

La0.67Sr0.16Ca0.17MnO3 perovskite was prepared by the solid-state reaction technique. Preliminary room-temperature structural studies confirm the formation of the sample in the rhombohedral structure. The electrical response was studied using the impedance spectroscopy technique over a broad frequency range (250 Hz 3 MHz). The results indicate that the electrical properties of the material are strongly dependent on temperature and frequency. Impedance spectrum analysis shows that the material can be described as a grain and grain boundary medium and permits to estimate the grain boundary contribution. Electronic conduction is found to be dominated by a thermally activated hopping of small polaron at high temperatures.