PHASE-TRANSITION IN PB5GE2ZRO11 CERAMICS

Polycrystalline samples of zirconium-doped lead germanate Pb5Ge2ZrO11 were prepared by a solid-state reaction technique. Preliminary X-ray s tudies show the formation of the single-phase compound and provided it s basic crystal structure. Dielectric constant (epsilon) and loss (tan delta) were measured as a function of temperature (room temperature t o 280 degrees C) at different frequencies. Dielectric anomaly and ferr oelectric phase transition observed at 160 degrees C was supported by our polarization studies. The activation energy of the sample was calc ulated from the dielectric data. (C) 1997 Published by Elsevier Scienc e B.V.