X-ray diffraction and Raman scattering investigations on Ba[Mg(1-x)/3ZrxTa2(1-x)/3]O3 solid solutions

Ba[Mg(1-x)/3ZrxTa2(1-x)/3]O-3 (BMZT, x = 0, 0.05, 0.10, 0.20, 0.30) solid solution ceramics were synthesized via the conventional solid-state reaction method. The crystal structures were studied via X-ray diffraction, and lattice vibrational modes were obtained via Raman spectroscopy. The results show that crystal symmetry increases with Zr4+ concentration from hexagonal to cubic structure, and the lattice constant as well as the degree of order decrease, accordingly. The ordered phases are transformed from the 1: 2 ordered structure to the 1:1 ordered structure. The Raman shifts of the A(1g)(O) modes have a positive correlation with the temperature coefficients of constant from x = 0 to x = 0.30 and also a positive correlation with the dielectric constants when x >= 0.20, as well as an inverse correlation with the dielectric constants when x <= 0.20 and the dielectric losses from x = 0 to x = 0.30. (C) 2013 Elsevier B. V. All rights reserved.