PHASE-TRANSITION IN PB5GE2TIO11 CERAMICS

Polycrystalline samples of Pb5Ge2TiO11 have been prepared by a high te mperature solid-state reaction technique. X-ray powder diffraction met hod has been used to check the quality and formation of the compounds. Measurements of dielectric constant (epsilon) and dielectric loss (ta n delta) as a function of temperature (room temperature to 240 degrees C) at 1, 10, 100 and 1000 kHz frequencies have shown a dielectric ano maly and phase transition at about 154 degrees C. Our studies on elect rical properties (i.e., ac and de) electrical conductivity and polariz ation of the material support the above results. (C) 1998 Elsevier Sci ence B.V. All rights reserved.