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Information × Registration Number 0207U002618, 0101U007082 , R & D reports Title Investigation of the random ferroelectric local structure caused relaxor state popup.stage_title Head Bykov Igor Pavlovich, Registration Date 06-02-2007 Organization I.N.Frantsevich Institute for Probmens of Materials Sciences Ukrainian Academy of Science popup.description2 NMR spectra of Pb ions related to glass matrix with Pb shift from cubic position was investigated in PMN. The presence of transition of oriental type was shown. NMR spectra of 207Pb, 45Sc and 93Nb nuclei were investigated in partially ordered relaxor ferroelectrics PSN at temperatures from 77 to 420 K. It was shown that effective local symmetry of PSN at T < 250 K decreases from axial rhombohedral to nonaxial orthorhombic and shift of Pb atoms strongly deviates from polar axis [111]. Theory of line shape of radiospectroscopy and dielectrics spectra of nanomaterials was presented. Ingomogeneous broadening of spectral lines for some types of nanoparticles size distribution was investigated. It was shown that splitting of original lines of bulk system spectra with decreasing of particle sizes is a characteristic feature of nanoparticle spectra. The model for calculation of properties of relaxor solid solutions in framework of random field theory was proposed. The dependences of order parameter and dielectric susceptibility on film thickness, temperature and parameters of random field distribution function were obtained. Obtained dependences of transition temperature and polarization of (PMN)1-x(PT)x solid solution demonstrate existence of morphotropic region in phase diagram. Calculated phase diagrams have a good agreement with those obtained experimentally. Product Description popup.authors popup.nrat_date 2020-04-02 Close