Ellipsometric studies of synclinic and anticlinic arrangements in liquid crystal films

The molecular arrangements in liquid crystal freestanding films are studied when smectic [Formula Presented] surface ordering occurs above the bulk smectic A to smectic [Formula Presented] transition temperature. Details of the resulting structures are resolved using ellipsometry. The behavior of the film is compound dependent. Below a critical electric field, either a synclinic or anticlinic structure may be present depending on the magnitude of the bulk spontaneous polarization. A model is presented in which the low-field anticlinic arrangement results from the interaction between polarization fluctuations at the two surfaces.