A COMPARATIVE STUDY ON THE STRUCTURAL, MAGNETIC AND ELECTRICAL PROPERTIES OF THE La0.67Ca0.33MnO3 SYNTHESIZE VIA CO PRECIPITATION METHOD AND SOLID-STATE REACTION

Abstract

The structural, magnetic and electrical properties of lanthanum manganites have been reported. La_0.67Ca_0.33MnO₃ sample synthesized via co-precipitation (COP) method with starting materials derived from metal acetates were compared to the specimens prepared by solid state route (SSR). The Curie temperature, T_C and the metal-insulator transition temperature, T_P were obtained by ac susceptibility and four- point probe techniques. The results showed that T_C and T_P were 260 K and 276 K respectively for the COP specimen, which is higher than the results obtained for specimen prepared by SSR with T_C and T_P were 245 K and 246 K respectively. These results are due to the high chemical homogeneity and high density for the COP specimen as compared to the SSR specimen. The CMR for the COP specimen is observed near the insulator- metal transition with the maximum value of (~ 56%) at 260 K for H = 1.06 T.