Electron transport and magnetic properties of La 1− xSr xCo 1− yTi yO 3 ( x = 0 a or x = yb)

Abstract

The two systems (a) and (b) for different values of x were synthesized. Their electron transport and magnetic properties show a change in behavior above a critical value of x. Unlike the system La 1− x Sr x CoO 3, itinerant electron ferromagnetism is not observed. This is explained on the basis of the absence of an itinerant band of Co 4+ whose generation is restricted on account of substitution of Ti 4+. Electron transport in these two systems is compared with that of LaCoO 3 or La 1− x Sr x CoO 3 and is discussed in view of the presence of different valence states of cobalt and change in crystal field splitting. Spin-state equilibria in these two systems are similar to that in LaCoO 3.