Theory of phase transitions in systems with defects and development of phenomenological theory of relaxors

ABSTRACT

Theory of phase transitions in systems with defects is considered and phenomenological theory of the diffuse phase transition has been proposed. The temperature behavior and dispersion of the dielectric properties in the region of the diffuse phase transition has been associated with the dynamics of the charge delocalization on defects. The consideration has been performed on the basis of simple thermodynamic ideas in the framework of the Sigov-Levanyuk approach to the phenomenological theory of phase transitions in the system with defects.

KEYWORDS:

• Phase transitions
• phenomenological theory
• relaxors

Acknowledgments

The work is performed according to the Russian Government Program of Competitive Growth of Kazan Federal University. The reported study was partially supported by RFBR, research project No. 14-02-01154 a.