Domain-wall orientations of PbYb sub( one half )Nb sub( one half )O sub(3)

Domain-wall orientations of antiferroelectric PbYb sub( one half )Nb sub( one half )O sub(3) were analyzed by group symmetry and spontaneous strain methods. Both of the methods indicate similar results. PbYb sub( one half )Nb sub( one half )O sub(3) has two types of domain-walls, i.e. W and W'-walls. The breaking of symmetry during ferroelastic transition occurs at (100), (010), (011), (01 1), (1 01) and (101) mirror planes of the cubic prototype. The W'-wall planes are approximately (2 33) sub(m), (23 3) sub(m), (3 23) sub(m) and (32 3) sub(m) at room temperature.