SCANNING TUNNELING MICROSCOPIC STUDY OF THE INTERFACIAL ORDER IN A FERROELECTRIC LIQUID-CRYSTAL

We present scanning tunnelling microscopy images of a ferroelectric liquid crystal in its chiral smectic C phase. These images show evidence of pronounced interaction between the adjacent lateral dipoles located near the chiral centres of neighbouring molecules. The two dimensional structure at the graphite-liquid crystal interface is found to be highly ordered. Features of this crystal-like order are the pronounced dimer arrangement within a layer and a kinked conformation in which the aromatic core is tilted with respect to the chains. The core axis is tilted at 30-degrees with respect to the layer normal in the plane of the interface. This tilt is very similar to the tilt angle of the bulk material