Temperature-dependent Raman scattering of DyScO3 and GdScO3 single crystals.

We report a temperature-dependent Raman scattering investigation of DyScO(3) and GdScO(3) single crystals from room temperature up to 1200 °C. With increasing temperature, all modes decrease monotonically in wavenumber without anomaly, which attests to the absence of a structural phase transition. The high temperature spectral signature and extrapolation of band positions to higher temperatures suggest a decreasing orthorhombic distortion towards the ideal cubic structure. Our study indicates that this orthorhombic-to-cubic phase transition is close to or higher than the melting point of both rare-earth scandates ([Formula: see text]), which might exclude the possibility of the experimental observation of such a phase transition before melting. The temperature-dependent shift of Raman phonons is also discussed in the context of thermal expansion.