Raman Scattering in Locally Inhomogeneous Oxide Crystals.

Local-scale atomic arrangements in three types of oxide crystalline materials with structural defects, self-bonded molecular sieves, ferroelastics and relaxor ferroelectricity, are investigated by Raman spectroscopy. The experimentally observed spectral data are analysed through normal mode calculations for structural species representative of the intermediate range order in the solid. In the case of molecular sieves, the important role of incipient structural species for producing crystalline silicalite-1 and zeolite beta spheres of mm size is shown. In the case of ferroelastics, further insights on structural perturbation across the domain walls in monoclinic Pb3(PO4)2 are provided. In the case of relaxors, the local structure and related dynamical effects in PbSc0.5Nb0.5O3 and PbSc0.5Nb0.5O3 is revealed. [ABSTRACT FROM AUTHOR]