Recently it was shown that smectic liquid crystal phases formed by achiral
banana-shaped molecules are chiral: Films of such phases generally contain
both homochiral (consisting of layers of the same chirality) and racemic (t
he chirality alternates in subsequent layers) domains. So far it has not be
en clear how to control the.. overall chirality of the sample;By observing
the effects of the application of suitable electric fields, it was;;noted t
hat chirality of a film of banana shaped molecules was interchanged between
homochiral and racemic. We present dielectric, electro-optic, and polariza
tion current measurements on both the racemic and chiral states. The observ
ations indicate that the synclinic states have minimum free energies. The o
bserved dielectric modes can be explained by a simple model assuming that t
he antiferroelectric state is very weak. [S1063-651X(99)19410-8].