Consequences of Bond-Orientational Order on the Macroscopic Orientation Patterns of Thin Tilted Hexatic Liquid-Crystal Films

Abstract

By use of depolarized laser relection microscopy, unique textural defects have been observed in thin tilted hexatic liquid-crystal films which result from their bond-orientational order. The temperature dependence of the bond-orientational elasticity can be deduced from these textural patterns and is in qualitative agreement with the theory of two-dimensional melting. The effects of molecular chirality and film thickness on the defect textures is also reported along with observations on the polygonization of the two-dimensional crystalline phase.