Ferroelectric perovskite-type barium copper niobate: BaCu1/3Nb2/3O3

摘要

A perovskite-type BaCu1/3Nb2/3O3 was prepared by high temperature reaction using BaCO3, CuO and Nb2O5. The X-ray powder diffraction pattern of this compound was indexed with the tetragonal cell with the lattice parameters of a = 4.0464(4) and c = 4.1807(4) angstrom (c/a = 1.033). This compound had the tetragonal perovskite-type structure in which the B site was occupied statistically by Nb and Cu atoms. From high temperature X-ray powder diffraction patterns this compound had a phase transition from the tetragonal to cubic symmetry in the temperature range of 500-600 degrees C. The P-E and S-E hysteresis loops occurred at room temperature and the apparent maximum in the temperature dependence of the dielectric constant was observed at 520 degrees C. The temperature dependence of the inverse of magnetic susceptibility exhibited paramagnetic behavior. (c) 2006 Elsevier Inc. All rights reserved.