Novel twist grain boundary smectic-C phases |
| |
Authors: | M Brunet L Navailles NA Clark |
| |
Institution: | (1) GDPC - UMR 5581, Université Montpellier II, F34095 Montpellier Cedex 05, France, FR;(2) Department of Physics, Ferroelectric Liquid Crystal Materials Research Center, University of Colorado, Boulder Boulder, CO, USA 80309, US |
| |
Abstract: | Several new kinds of smectic-C twist grain boundary phases (TGBC) have been observed during the last few years. These pure
compounds or mixtures exhibit unusual textures with polygonal lattices (square or hexagonal grids) in the plane normal to
the TGB helix. The structure of these new phases seems to be complex and different from reported and predicted TGBC phases.
In this article, we review the main results obtained on these different new phases, and we propose new TGBC structures based
on the well-known splayed polarization --twisted director structures adopted by chiral smectic-C's in planar aligned (bookshelf)
cells. The observed square or hexagonal lattices are made of superimposed pairs of unwinding lines due to the suppression
of the helix within smectic-C blocks by the grain boundaries (unwinding walls). A lattice-free TGBC occurs if the helix within
smectic-C blocks is suppressed completely.
Received 15 March 2001 |
| |
Keywords: | PACS 61 30 -v Liquid crystals – 61 30 Jf Defects in liquid crystals – 61 30 Eb Experimental determinations of smectic nematic cholesteric and other structures |
本文献已被 SpringerLink 等数据库收录! |
|