Disorder-induced Raman scattering in rhenium trioxide (ReO3)

Raman scattering in cubic metallic perovskite (ReO3) was studied at room temperature for well-crystallized monolith, polycrystalline powder and thin film samples. Defect-induced first-order Raman scattering was detected from the sub-surface region, given by the penetration depth of a 633 nm laser, and its origin was explained on the basis of a rigid-ion vibrationalmodel for bulk ReO3. A quenching of the Raman intensity was observed in crystalline monolithic ReO3 upon increasing the temperature up to 250 degrees C and was related to crystal surface reconstruction/annealing.