Theory and simulation of freeze-fracture in cholesteric liquid crystals

A theory of fracture in spatially varying anisotropic glass is developed to interpret electron micrographs of freeze-fractured surfaces of cholesteric samples. The expression for energy per unit area released by crack formation is [n(1+bQ1)n]12, where Q1 is the traceless Landau tensor for unit order parameter and n is a unit vector normal to the crack surface. The two parameters of the theory are b, which is a function of the ratio of length to width of molecule, and a crack-precursor length. Contours closely matching those observed in the laminar cholesteric texture and in blue phase I are generated.