Steric effects and electron doping in Sr2CrReO6 double-perovskite oxides

The study of electron-doped Sr2-xNdxCrReO6 half-metallic double perovkites has been carried out. Detailed characterization by means of X-ray diffraction (XRD), scanning electron microscopy (SEM) and magnetization measurements was done. XRD and SEM measurements indicate that the desired stoichiometry is obtained up to Sr substitution around 25%. Magnetization measurements as a function of temperature (up to 800 K) in the Nd-substituted compounds indicate that substantial modification of the Curie temperature does not occur for the investigated level of Nd doping. The values of the saturation magnetization at 5 K for the compounds are consistent with additional electrons being promoted to the conduction band with magnetic moment antiparallel to the localized moment. (c) 2007 Elsevier B.V. All rights reserved.