High temperature phase transformations in dysprosium titanate

High temperature phase transformations of rare earth titanates have been studied in-situ using synchrotron X-rays. Phase transformations from the low temperature cubic phase over an orthorhombic and hexagonal phase to a high temperature cubic phase could be monitored using Rietveld refinements of high resolution synchrotron data. Lattice parameters, thermal expansion coefficients and unit cell volumes could be determined over a temperature range from room temperature to∼ 1800. °C. Point group symmetries were investigated by transmission electron microscopy using the convergent beam technique (CBED), so that the correct space group symmetry could be elucidated.