Structural Order–Disorder Transformations Monitored by X-ray Diffraction and Photoluminescence

This experiment introduces to students the X-ray diffraction and photoluminescence spectroscopy techniques as tools to verify structural order–disorder transformations in solid-state materials. To achieve this goal, Sm3+ ions were added to a PbTiO3 lattice by soft chemical synthesis—the so-called polymeric precursor method. After a controlled heat treatment, the presence of these ions in the PbTiO3 matrix revealed the three order states of solid matter: the short- (disordered structure), intermediate-, and long-range (crystalline or ordered structure) states.