Dielectric properties of Ba sub(2)YMoO sub(6) ceramics

Double-perovskite Ba sub(2)YMoO sub(6) ceramics were prepared via the solid-state reaction route. Their dielectric properties were investigated as a function of temperature (100 [degrees]C [< or =] T [< or =] 800 [degrees]C) and frequency (300 Hz [< or =] f [< or =] 5 MHz). In the temperature below 600 [degrees]C, two thermally activated dielectric relaxations can be well identified. The low-temperature relaxation was ascribed to be a dipolar relaxation caused by oxygen vacancy diffusion, and the high-temperature relaxation is found to be a Maxwell-Wagner relaxation due to surface-layer effect.