Textural transformations of a smectic phase with asymmetric banana-shaped molecules

Abstract

Materials consisting of asymmetric banana-shaped molecules may form a smectic C G phase having C 1 symmetry. We have studied textural transformations in a smectic phase of an asymmetric chlorine-substituted banana-shaped material under electric and mechanical elds. We observed two novel features that have not been observed so far on corresponding materials with symmetric banana-shaped molecules. These observations, however, could be explained by the same arguments as were used for the symmetric molecules. Although our studies do not exclude the possibility that the material has C 1 symmetry, we suggest that the chlorine molecules are positioned arbitrarily and the bulk has C 2 symmetry.

Side-Chain Liquid Crystalline Poly(meth)acrylates with Bent-Core Mesogens

“…Since most of bent-core molecules contain symmetric chemical structures, symmetrically modifying the mesogens with polymerizable groups has been first attempted in the literature. However, asymmetric BCLCs have attracted great attention recently because they may exhibit new phase behavior. − For asymmetric bent-core mesogen synthesis, the most considered strategy is tuning the feed ratio of the two reactants of esterification to achieve monosubstituted products. In this case, the disubstituted product is regarded as the byproduct which is unavoidable.…”

“…However, asymmetric BCLCs have attracted great attention recently because they may exhibit new phase behavior. [36][37][38][39][40] For asymmetric bent-core mesogen synthesis, the most considered strategy is tuning the feed ratio of the two reactants of esterification to achieve monosubstituted products. In this case, the disubstituted product is regarded as the byproduct which is unavoidable.…”

Bent-Core Liquid Crystals: Their Mysterious and Attractive World

“…20. 36,[82][83][84][85][86][87] The most typical texture is a spiral filament as shown in Fig. 20(a).…”

Evidence for Triclinic Symmetry in Smectic Liquid Crystals of Bent-Shape Molecules

“…In bulk first the B 2 phase of asymmetric banana-shaped molecules were examined, but textural observations could not provide conclusive results [10]. On the other hand, microscopic observations on the B 7 phase revealed the coexistence of 4 states with different birefringences and electrical responses [11] suggesting that they represent Sm-C G structures corresponding to Figs.…”