Structural transitions in thin free-standing films of an antiferroelectric liquid crystal exhibiting the smectic-C(*)(alpha) phase in the bulk sample.

Optical reflectivity studies have been conducted upon thin free-standing films of an antiferroelectric liquid crystal possessing the bulk phase sequence Sm C()(A)-Sm C()(alpha)-Sm A. Electrically induced field independent and field dependent structural transformations were observed above the bulk Sm C()(A)-Sm C()(alpha) transition temperature. The anisotropy of the reflectivity was measured for different states in thin films. Our data provide direct evidence of structures without the short-pitched helix in the temperature region between the antiferroelectric Sm C(*)(A) and untilted Sm A structures.