Ferroelectric-antiferroelectric mixed systems. Equation of state, thermodynamic functions

Abstract

The problem of equation of state for ferroelectric-antiferroelectric mixed systems in the whole region of a concentration change (06n61) is discussed. The main peculiarity of the presented model turns out to be the possibility for the site dipole momentum to be oriented ferroelectrically in z-direction and antiferroelectrically in x-direction. Such a situation takes place in mixed compounds of KDP type. The different phases (ferro-, antiferro-, paraelectric, dipole glass and some combinations of them) have been found and analyzed.