The molecular self-diffusion in smectic LC monolayers is investigated by molecular dynamics (MD) simulation. Except for the very early stage, the mean square displacement (MSD) of the LC molecules showed a linear increase with time, indicating the normal diffusion of ordinary liquids. The 2D diffusion constant calculated from MSD was almost equal to the one for biomembranes and the 2D viscosity showed a good agreement with the experimental value.
