Structural stability and electrical properties of Sr2Fe1+xMo1-xO6-delta under high pressure

Fe-substituted materials SrFe1+xMo1-xO6-delta (x = 0, 0.1, 0.2, 0.3, 0.4) were synthesized by a modified polymer-network gel method at a relatively low temperature. The structural stability and electrical properties of Sr2FeMoO6 and Sr2Fe1.4Mo6-delta have been studied using energy dispersive X-ray diffraction with synchrotron radiation and resistance and capacitance measurements, respectively. The results show that the crystal structure of Sr2Fe1.4Mo0.6O6-delta is as stable as Sr2FeMoO6 at high pressure and more compressible than Sr2FeMoO6. On the basis of the measurements of resistance and capacitance versus pressure, it is considered that they all undergo an electronic structure transition under high pressure. (C) 2004 Elsevier B.V. All rights reserved.