Micromechanics Model of Liquid Crystal Anisotropic Triple Lines with Applications to Self-Assembly

Abstract

Directed self-assembly of mesophases at three phase contact lines has been reported for a variety of solutions, including micelles, tobacco mosaic virus, DNA, silk, and others, through the action of capillary forces, wetting processes, and/or evaporation. This communication presents a new micromechanical line-excess model of the anisotropic contact line tension for nematic liquid crystal phases, which incorporates well characterized liquid crystal interfacial tensions. The anisotropic line tension is then used to formulate the contact line torque that promotes the azimuthal orientation, widely reported experimentally. The dependence of the line torque strength on the contact angle reveals the conditions that promote azimuthal orientational ordering close to the contact line. This work is limited to anisotropic line-excess tension, and wetting and evaporation processes are outside its scope.