Improper ferroelectric phase transition in cadmium pyroniobate

The processes of domain switching and conversion of a crystal to the single-domain state under the influence of a static electric field was studied for the improper ferroelectric phase of Cd 2 Nb 2 O 7 . A study was made of the influence of uniaxial mechanical stresses applied along different crystallographic directions on the permittivity e in the region of the improper ferroelectric transition at T 1 =205 K. A phenomenological theory was used in an analysis of the influence of uniaxial compression on this phase transition