Raman scattering study of phase transition in Lu 2 O 3 –Ta 2 O 5

The lutetium tantalate compounds obtained from Lu2O3–Ta2O5 with a molar ratio of 0.515:0.485 were studied by Raman scattering and x-ray diffraction. The results of the room temperature Raman scattering indicate that the sample has a phase transition between 1830 °C and 1872 °C, the polycrystalline is a mixture of M'-LuTaO4 and when it is prepared at 1830 °C, and a mixture of M-LuTaO4(B112/b) and when it is prepared at above 1872 °C. The sample melts at a temperature of 2050 °C. The phase transition of the sample prepared at 2050 °C was also investigated by the high-temperature Raman spectra, and the result indicates that no phase transition occurs between room temperature and 1400 °C, which is consistent with the results from the x-ray diffraction.