Effective macroscopic symmetries and materials properties of multidomain 0.955Pb(Zn1/3Nb2/3)O3-0.045PbTiO3 single crystals

The crystal symmetry of a 0.955Pb(Zn1/3Nb2/3)O-3-0.045PbTiO(3) (PZN-4.5%PT) single crystal is rhombohedral 3m. It is in multidomain state after being poled along [001] of its original cubic coordinates. Although most studies on this system assumed the tetragonal 4mm effective symmetry, experimental observations show that many of the crystals actually have effective orthorhombic mm2 symmetry. Some crystal domain patterns may even become monoclinic m or even lower in symmetry. In other words, domains form a hierarchical symmetry, which controls the effective materials properties of the multidomain system. We report an analysis of the domain symmetry involved and a full set of materials properties measured in crystals having only two of the four possible domains based on mm2 symmetry. (C) 2002 American Institute of Physics.