Crystal symmetry in single domains of PbZr0.54Ti0.46O3

This work focuses on the crystal symmetry of morphotropic PbZrxTi1-xO3 (PZT). The crystal symmetry is investigated within single domains of approximate to 30-100 nm width by convergent beam electron diffraction (CBED). The composition PbZr0.54Ti0.46O3 was chosen for experiments at room temperature and approximate to 300 degrees C. The observed zone axis symmetry at room temperature was a ((1) over bar 10) mirror in some domains whereas symmetry was broken in neighboring domains. Therefore the highest crystal symmetry that can be attributed with certainty to the probed volume is monoclinic. The local symmetry of single cells might be lower due to disordered displacements of the cations. At approximate to 300 degrees C the zone axis symmetry had changed to a (100)(pc) mirror that only occurs in the tetragonal phase of PZT.