Structural changes of SrGeO3 under high pressures and temperatures

Abstract

Using a large volume high-pressure apparatus and a synchrotron radiation facility, the local structures around germanium in SrGeO3 have been investigated by in situ X-ray absorption fine structure (XAFS) measurements up to 10 GPa at room temperature and 1600K. The transition between SrGeO3 II and SrGeO3 perovskite occurs at 5 GPa and room temperature. In liquid SrGeO3, Ge-O bond length elongates gradually over a pressure range from 3 to 10 GPa. The observed elongation of Ge-O bond length would be attributed to the continuous increase of coordination number of Ge atoms.