Reentrant ferroelectricity in liquid crystals

The ferroelectric (Sm C-*)-antiferroelectric (Sm C-A(*))-reentrant ferroele ctric (re Sm C-*) phase temperature sequence was observed for systems with competing synclinic-anticlinic interactions. The basic properties of this s ystem are as follows: (i) the Sm C-* phase is metastable in the temperature range of the Sm C-A(*): (ii) the helix handedness inverts at both Sm C-* S m C-A(*) and Sm C-A(*)-re-Sm C-* phase transitions; (iii) the threshold ele ctric held that is necessary to induce synclinic ordering in the Sm C-A(*) phase decreases near both Sm C-A(*)-Sm C-* and Sm C-A(*)-re-Sm C-* phase bo undaries. All these properties are properly described by a simple Landau mo del that accounts for nearest neighboring layer steric interactions and qua drupolar ordering only.