STRUCTURAL AND ELECTRICAL-PROPERTIES OF PB5GE2.5TI0.5O11 FERROELECTRICS

Polycrystalline samples of titanium doped lead germanate Pb5Ge2.5Ti0.5 O11 were prepared by solid-state reaction technique. Preliminary X-ray studies have been carried out to check the formation of the single ph ase compound and to determine its basic crystal structure. Studies of dielectric constant (epsilon) and loss (tan delta) have been carried o ut as a function of temperature (from room temperature to 260 degrees C) at 1, 10, 100 and 1000 kHz which show a dielectric anomaly at about 164 +/- 1 degrees C. Variation of polarization as a function has been obtained in the above temperature range. The transition temperature o f the Pb5Ge3O11 compound decreases with doping of titanium ion and the nature of phase transition is of second order.