Crystal structure and magnetic properties of Y-2(Cu1-xMgx)(2)O-5 obtained by SHS method

Abstract

The single-phase polycrystalline samples of Y-2(Cu1-xMgx)(2)O-5, x = 0.0, 0.05, 0.15 were successfully synthesized by a modified self-propagating high temperature synthesis. Effects of Mg+2 substitution for Cu+2 in metamagnetic Y2Cu2O5 on its crystal structure and magnetic properties have been analyzed by X-ray diffraction and magnetic measurements performed within 2-300 K range. Mg doping was found to introduce small distortions in the main intradimmer superexchange paths so that ferromagnetic correlations decrease with Mg concentration. More significant impact of Cu substitution was found on the low temperature magnetism due to the breaking of infinite Cu-O chains. The formation of finite size chains introduces low temperature paramagnetic contribution and reduction in Neel temperature. Overall results give a strong indication that the antiferromagnetic ordering as well as metamagnetism persists up to the 15% of the Mg concentration. (C) 2013 Elsevier B.V. All rights reserved.