Phase Transitions in Solid Solutions of PbZrO₃and PbTiO₃(II) X-ray Study

Abstract

The phase diagram of the whole range of the PbZrO 3 -PbTiO 3 system was determined by the dielectric and dilatometric measurements. According to the reason shown in part I, this phase diagram can be divided into three regiors; paraelectric, ferroelectric and antiferroelectric phases. The crystal structure of this system was determined by the Debye photographs. In the antiferroelectric region solid solutions have a tetragonal modification of perovskite structure with c / a <1 and have some superstructure which seems to have intimate relation to the antiferroelectricity. In the ferroelectric region, except a region near antiferroelectric phase in which pseudocubic structure is observed, they have ordinary tetragonal structure of c / a >1 without any superstructure.