Effect of bond valence on microwave dielectric properties of (Pb_1-xCa_x)(Mg_0.33Ta_0.67) ceramics

摘要

The relationship between the dielectric properties of the complex perovskite (Pb_1-xCa_x)(Mg_0.33Ta_0.67)O_3 ceramics, where 0.45≤X≤0.60, and the dielectric polarizability, related to bond valences of A-site ions, was investigated at microwave frequencies. As the Ca content(x)increased, the deviation of the observed dielectric polarizabilities, calculated by the Clausius-Mosotti equation from the theoretical values calculated by the additivity rule of dielectric polarizability, decreased from -3/100 to -0.69/100. It was found that this deviation was related to the bond valence of the A-site.