The effect of Sn for Ti substitution on the crystal structure of a perovskite, barium titanate stannate (BTS), BaTi1−xSnxO3 for x = 0, 0.025, 0.05, 0.07, 0.10, 0.12, 0.15 and 0.20, was investigated. The powders were prepared by the conventional solid‐state reaction technique. The structural investigations of the BTS powders were done at room temperature by X‐ray powder diffraction (XRD), transmission electron microscopy (TEM), high‐resolution TEM (HRTEM), selected‐area electron diffraction (SAED) and Raman spectroscopy analyses. Rietveld refinement of XRD data indicates that gradual replacement of titanium by tin in BaTiO3 provokes a phase transition from tetragonal for 0 ≤x≤ 0.07 to cubic for x = 0.12, 0.15 and 0.20. The coexistence of tetragonal (P4mm) and cubic (Pmm) crystal phases was established in powder with nominal composition BaTi0.9Sn0.1O3. The crystal phases determined by Rietveld refinement were confirmed by HRTEM and SAED analyses. The crystal structures of the BTS powders at short‐range scale were studied by Raman spectroscopy, which shows tetragonal (P4mm) and a small fraction of orthorhombic (Pmm2) crystal phases for all the examined BTS powders, implying a lower local ordering when compared to the average symmetry.

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Properties of CdS thin films were investigated applying atomic force microscopy (AFM) and Raman spectroscopy. CdS thin films were prepared by using thermal evaporation technique under base pressure 2 x 10-5 torr. The quality of these films was investigated by AFM spectroscopy. We apply Raman scattering to investigate optical properties of CdS thin films, and reveal existence of surface optical phonon (SOP) mode at 297 cm-1. Effective permittivity of mixture were modeled by Maxwell - Garnet approximation. [Projekat Ministarstva nauke Republike Srbije, br. 45003]

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Nanocrystalline samples of ZnO(Fe) were synthesized by wet chemical method. Samples were characterized by X-ray diffraction to determine composition of the samples (ZnO, Fe2O3, ZnFe2O4) and the mean crystalline size (8-52 nm). In this paper we report the experimental spectra of the Raman scattering (from 200 to 1600 cm −1). Main characteristics of experimental Raman spectrum in 200 to 1600 cm −1 spectral region are: sharp peak at 436 cm −1 and broad two-phonon structure at ≈ 1150 cm −1 , typical of ZnO; broad structure below 700 cm −1 that has different position and shape in case of ZnFe 2 O 4 or Fe 2 O 3 nanoparticles.