抄録
The alignment order of liquid crystals is affected by the existence of interfaces or surfaces. We consider a system of simple model molecules to discuss the behavior of the orientational order of liquid crystals around surfaces. The model molecules are rectangular parallelepipeds with length l and square cross-section of width d. Each edge of the parallelepipeds are assumed to be parallel to one of x-, y- and z-axis of Cartesian coordinates. Only the hard core repulsive force is considered for molecular interaction. Our mean field theory shows that the hard core repulsive force favors the homeotropic alignment on the free surface. It also shows that in the nematic phase, the orientational order on the free surface is lower than the orientational order of tile bulk.
