Pressure-induced structural and vibrational evolution in ferroelectric RInO3 (R=Eu, Gd, Dy)

The structural and vibrational properties of the hexagonal indates RInO3 (R=Eu, Gd and Dy) have been studied under high pressures using synchrotron x-ray diffraction and Raman scattering in diamond anvil cells. The three hexagonal structures exhibit anisotropic compression behaviors under high pressures and are stable up to similar to 17 GPa. High-pressure Raman spectra show that most frequencies harden linearly with different rates under high pressures. At similar to 17 GPa, three compounds undergo similar phase transitions. It is hard to indentify the structure of the high-pressure phase due to the broad x-ray diffraction and Raman patterns which could result from the kinetic hindrance of the phase transition at room temperature. (C) 2013 Elsevier Ltd. All rights reserved.