Дослідження полярних нанокластерів у твердих розчинах (PMN)1−x−(PT)x методом ЯМР

Abstract

The investigation of NMR spectra of ²⁰⁷Pb and ⁹³Nb nuclei in the relaxor ferroelectric ceramics PbMg₁/₃Nb₂/₃O₃ and a solid solution (1−x) PbMg₁/₃Nb₂/₃O₃₋xPbTiO₃ is carried out. The basic mechanisms (chemical shift, quadrupole coupling) determining the characteristics of ²⁰⁷Pb and ⁹³Nb resonance spectra are studied. Spin-spin and spin-lattice relaxations for ²⁰⁷Pb ions (spin 1/2) in these materials are measured for the first time. It is established that fluctuations of the orientations and the sizes of polar nanoclusters are the main reasons of both the dielectric relaxation and the nuclear magnetization relaxation.