Probable realization of rotor systems in SrTiO3 and PbZr1−xTixO3

Rotor descriptions of some perovskite compounds and alloys are possibly shown. Temperature behavior of a quantity (T1) in SrTiO3 are discussed. T1 is argued to serve as fingerprints in identifying the nature of a local mode. It is found with a dip around 105 K, which defies usual wisdom but proves explicable by both the eight-corner and the rotor model. A mapping may exist between these models. We then model PbZr1−xTixO3 as a lattice of rotors with randomly distributed cubic anisotropy. The x-driven transition is argued to be of percolation type. Consequences are discussed and shown agreeing with observations.