Computer simulations of discotic liquid crystals in nanoconfinement

Abstract

Discotics, that is liquid crystals formed by disk-like molecules, draw interest due to their applications as conductive nanowires confined in nanoporous templates. In this work we study the influence of different sizes of cylindrical nanoconfinement and surface anchoring on the phase behaviour of a discotic Gay-Berne fluid. The phase behaviour strongly differs from the bulk. We observe radially aligned nematic and radial poly-domain columnar configurations. Mono-domain hexagonal columnar phases were found with both face- and edge-on anchoring. Furthermore, geometrical frustration of hexagonal columnar and crystal phases is observed. Smaller pores with edge-on anchoring exhibit a configuration with a columnar outer layer and an isotropic core. The phase behaviour is investigated by means of several order parameters, some specific for the special orientational configuration in cylindrical confinement. We investigate the structure by means of radial distribution functions, and the dynamics using van Hove correlation functions