Dielectric properties and phase transition in CaCU3Ti4O12 at high temperatures

The dielectric properties, and structural behavior of perovskite-related CaCu3Ti4O12 were studied at high temperatures. The dielectric constant increase gradually with incrreasing temperature and shows a shoulder-like round anomaly at approximately 630K at 10 kHz. At 732K a new dielectric anomaly was found, where the peak value of the dielectric constant epsilon peak similar or equal to 2.8 x 10(6) at a frequency of 10 kHz. The lattice constant and X-ray intensity of the (880) reflection also exhibit an anomaly at 732K. These findings indicate that CaCu3Ti4O12 undergoes a structural phase transition at 732K.