LAYER-THINNING TRANSITIONS IN FREELY SUSPENDED SMECTIC-A FILMS

We outline the elements of a mean-field density functional theory of i nhomogeneous liquid crystals which is able to account for surface-enha nced smectic ordering (SESO) at a free surface. The theory generates S ESO without requiring an external anchoring potential, and depending o nly on the properties (i.e., strengths and ranges) of the anisotropic intermolecular forces. Application of the theory to explaining recent experimental findings of layer-thinning transitions in freely suspende d smectic-A films is briefly summarized.