Electric-field-induced chiral separation in-liquid crystals

Citation
G. Heppke et al., Electric-field-induced chiral separation in-liquid crystals, PHYS REV E, 60(5), 1999, pp. 5575-5579
Citations number
19
Categorie Soggetti
Physics
Journal title
PHYSICAL REVIEW E
ISSN journal
1063651X → ACNP
Volume
60
Issue
5
Year of publication
1999
Part
A
Pages
5575 - 5579
Database
ISI
SICI code
1063-651X(199911)60:5<5575:ECSIC>2.0.ZU;2-X
Abstract
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].