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In this paper, we report structural analysis, ferroelectric behavior and electronic structure of Sr 2 ZrTiO 6 double perovskite. Samples were produced by the solid state reaction recipe. Crystallographic analysis was performed by Rietveld refinement of experimental X-ray diffraction patterns. Results show that this material crystallizes in a tetragonal perovskite structure which corresponds to the space group I4/m. The curve of polarization as a function of applied voltage evidences a ferroelectric character with saturation polarization on the application of voltages up to 1800 V. Calculations of density of states and band structure for this manganite-like material were carried out by means of the density functional theory implemented into the Wien2k code. Results of total and partial density of states reveal the insulator character of this material with an energy gap of 2.66 eV.

A single crystallographic phase of the Ba2YbSbO6 perovskite was synthesized by the solid-state reaction method. From the refinement of the XRD pattern it was obtained that this sintered material crystallizes in a rhombohedral complex perovskite, R-3 (#148) space group. SEM images showed the sub-micrometric character of its granular surface. Measurements of susceptibility as a function of temperature evidenced the antiferromagnetic behavior of this material below the Néel temperature TN=118 K and a paramagnetic feature above this critical temperature. The magnetic parameters were obtained from the fitting of susceptibility in the paramagnetic regime with the Curie-Weiss equation. From theoretically calculated Density of States and band structure the semiconductor characteristic of the material was determined and the energy gap was predicted for the up and down spin orientations of the electron gas close to the Fermi level. The energy gap value was experimentally corroborated from diffuse reflectance spectra with the Kubelka-Munk fit of the experimental result. Measurements of dielectric constant as a function of applied frequencies at room temperature reveal a decreasing behavior.

Ca1-xMgxCu3Ti4O12 material has been synthesized by chemical route for different compositions and thin films have been deposited by spin coating. X-ray diffraction and Raman spectroscopy were used for detailed characterization of this material for both powder and thin films. X-ray diffraction shows single phase film material for different compositions x < 0.80. The initial measurements on dielectric response indicates high dielectric constant > 10, 000 for the composition x = 0.1.