Crystal and domain structures of PbZrO₃

Abstract

Thin single crystals of PbZrO₃ were examined by usual electron diffraction. At room temperature diffraction patterns peculiar to the antiferroelectric phase were observed, that is the periodicity of diffraction spots along the [110]_c direction of the cubic phase is four times that obtained from the cubic phase. A new phase has been found in the temperature range from about 200°C to 230°C. The transition temperature to the intermediate phase differs about ten degrees from sample to sample. The diffraction patterns from the phase show that the periodicities of diffraction spots along the [110]_c and [1110]_c directions are about twice those of the cubic phase By close inspection the axial ratio b/a has been measured to be 1.006 at 200°C. The antiferroelectric phase transforms abruptly into the intermediate phase (the first-order transition) and it transforms gradually into the paraelectric phase (the second-order).