Models of Diffusion in Lyotropic Liquid Crystals

The asymmetric diffusion of small molecules in a liquid crystal host is examined via three models. The small molecules are represented by spheres and the liquid crystal host by aligned cylinders. DASH is a continuum model which allows one to use the results of electrical conductivity problems to calculate the diffusion coefficient. LASH is an extension of polymer lattice counting models. CASH is a molecular dynamics computer simulation which provides experimental data to check the analytical models. It is found that DASH is a better representation of the diffusion asymmetry than LASH for the low liquid crystal densities examined on the computer. The cylinder sphere pair correlation function is also calculated in CASH and this gives evidence for liquid order around the liquid crystals.