Peculiarities and properties of SbSI electroceramics

SbSI ferroelectric electroceramics has been developed with the increased Cu rie temperature (T-c = 58 degreesC). Below T-c, the electroceramics possess high volume piezoelectric modulus and other parameters important for appli cations. Microwave and far IR studies reveled that the main dielectric disp ersion lies in the range 1-100 GHz. Ab initio calculations of the soft B-1u mode potential have shown that in paraelectric (PE) phase on approaching T -c it becomes of a double well form. The high harmonicity splits the soft m ode. The lowest frequency component lies at microwaves and gives the main c ontribution (Delta epsilon (m) = 25,0000) to static permittivity which foll ows the Curie-Weiss law. The contribution of IR component (Delta epsilon (I R) = 1500) weakly depends on temperature. (C) 2001 Elsevier Science Ltd. Al l rights reserved.