X-ray, dielectric and high pressure studies on a compound exhibiting ferro-, ferri- and antiferroelectric smectic phases

Abstract

We report X-ray layer spacing, dielectric constant and high pressure measurements on a compound that exhibits the following sequence of phase transitions: smectic A-ferroelectric smectic C*-ferrielectric smectic C y*-antiferroelectric smectic CA *-hexatic antiferroelectric smectic IA *-crystal K. The pressure-temperature diagram shows two three-phase meeting points, which are topologically consistent with critical end points, and reentrant behavior of the C* and C* phases as the pressure is varied at constant temperature.