Structural and magnetic properties of Zn 1−xSb xCr 2−x/3Se 4 ( x=0.11, 0.16 and 0.20) single crystals

Abstract

Single crystals of Zn 1− x Sb x Cr 2− x /3Se 4 based on the ZnCr 2Se 4 spinel, which is known to exhibit interesting magnetic and electronic transport properties, have been prepared by solid state reaction from the appropriate selenides. Three compounds of different Sb content ( x=0.11, 0.16, and 0.20) were studied by X-ray diffraction, X-ray photoelectron scattering technique and macroscopic magnetic measurements with the aim to determine (i) stability of the cubic symmetry and (ii) influence of the Sb admixture on the magnetic properties. The results show that the Sb 3+ and Zn 2+ ions share the tetrahedral sites in the spinel structure, while the Cr 3+ions carrying magnetic moments, are located in the octahedral sites. The X-ray photoelectron spectroscopy (XPS) data indicate that in this series of compounds the chromium ions have a 3 d 3 electronic configuration. The three samples studied order antiferromagnetically at low temperatures, with the magnetic characteristics being hardly altered with respect to those reported for the parent ZnCr 2Se 4 compound.