Reduction of the number of polarization vectors in multiaxial ferroelectrics by means of chiral dopants. Macroscopic symmetry conditions

Abstract

The concept of covariance of polarization and enantiomorphism, introduced for uniaxial ferroelectrics in a previous paper, is generalized to multiaxial ferroelectrics. This covariance is a necessary condition for the reduction of the number of polarization vectors by means of chiral dopants. It imposes requirements on the point symmetry groups of parent and ferroic phases and on the stabilizer of the ferroelectric axis in the parent phase symmetry group. The table of corresponding phase transitions and the list of particular crystals fulfilling these conditions are given.