Crystal Structure and Phase Transitions of Intermediate Phase of PbZrO3

Abstract

Crystal structure of intermediate phase of PbZrO 3 was analyzed by neutron powder diffraction. Superlattice reflections of our sample appeared at M and R points. Intensities of fundamental reflections also changed in the phase. The structural modulations were associated with modes either Γ 15 + M 3 + R 25 or Γ 15 + M ′ 5 + R 25 . The modulation associated with the R 25 mode of our sample might be caused by an extrinsic origin. Dielectric constant was also measured and a mechanism of the phase transitions is discussed briefly.