Abstract
We report here an anomalous peak in the composition dependence of the dielectric permittivity of non-ferroelectric ceramics for the composition range . This is reminiscent of a similar phenomenon in the ferroelectric morphotropic phase boundary ceramics. Rietveld analysis of the powder x-ray diffraction data for various compositions reveals that this peak is linked with a change of crystal structure from one orthorhombic phase in the space group for to another orthorhombic phase in the space group for through an intermediate long period modulated orthorhombic phase whose lattice parameter is times the lattice parameter of the phase of in the [010] direction .
- Received 1 December 2006
DOI:https://doi.org/10.1103/PhysRevB.77.052104
©2008 American Physical Society