PRESSURE-INDUCED DIELECTRIC CHANGE FROM RELAXOR TO ANTIFERROELECTRIC BEHAVIOR IN DISORDERED PB(IN1 2NB1/2)O-3/

The dielectric properties of Pb(In1/2Nb1/2)O-3 (abbreviated as PIN) si ngle crystal were investigated under hydrostatic pressures up to 0.7 G Pa. The ordered PIN nas confirmed to be antiferroelectric by observati on of clear P-E double hysteresis loops below the transition temperatu re. There is a striking pressure effect in the disordered PIN. The rel axer behavior becomes less notable with increasing pressure and disapp ears at 0.4 GPa. At pressures above 0.4 GPa, the normal phase transiti on without dielectric dispersion in the low frequency range takes plac e and with increasing pressure, the temperature T-m, indicating the ma ximum of the dielectric constant, epsilon(rm)', increases at at rate o f 150 K/GPa and the epsilon(rm)' decreases. Such dielectric phenomena with pressure are similar to those observed in antiferroelectric PbZrO 3.