Investigation of structural, magnetic and electric transport properties of half-doped chromium manganites La0.3R0.2Sr0.5Mn0.5Cr0.5O3 (R=La, Nd, Sm, and Gd)

The effect of smaller rare-earth substitution in the La site of La0.5Sr0.5Mn0.5Cr0.5O3 has been investigated to elucidate how the properties of this material change with La doping. La0.3R0.2Sr0.5Mn0.5Cr0.5O3 (R=La, Nd, Sm, and Gd) compounds have been studied by X-ray diffraction and magnetic and transport measurements. All the samples were determined to be single phase and crystallized in an orthorhombic structure. Magnetic measurements showed that doping of smaller rare-earth ion for La decreases both Curie temperature (T-C) and Weiss constant (theta). Except R=La, all the phases follow Curie Weiss law in the high temperature region. All the samples are semiconducting and the transport properties are dominated by the adiabatic small polaron hopping mechanism. (C) 2015 Elsevier Ltd and Techna Group S.r.l. All rights reserved.