Layer Structures of Ferroelectric Smectic Liquid Crystals Formed by Bent-Core Molecules

Achiral bent-shaped molecules may form chiral and polar smectic phases, due to a spontaneous tilt of the planes of the molecules. The lowest energy-state is racemic, and in the textures of the ground state usually fine fringes appear parallel to the smectic layers. Recently it was found that the formation of the fringes could be suppressed resulting in a uniform texture in the ground state. In this paper we show evidences for field induced tilted and horizontally zigzagging layer structures. We discuss properties of various layer structures and compare them to our experimental observations. Finally we give a qualitative explanation for the observed field-induced-uniform-racemic ground state.