Analysis of the intralayer molecular orientation in the B1 phase of a bent-core liquid crystal molecule using X-ray microbeam(New Frontiers in Colloidal Physics : A Bridge between Micro- and Macroscopic Concepts in Soft Matter)

Abstract

アキラル屈曲型液晶のB1相構造に関して、X線マイクロビームでその配向解析を行った。結果、これまで提案されていた2つの構造のうち、Col(pm2_1m)の対称性を持つ屈曲面に垂直な面内に2次元周期構造を有することがわかった。

Achiral bent-core liquid crystals are very interesting from a viewpoint of "chiralily" which appears in an "achiral" molecular system, and have been investigated experimentally and theoretically by many researchers. The bent-core molecules exhibit specific mesogenic phases, B1～B8, different from those in rod-like molecules. The determination of the structure in each phase is crucial but difficult, because of difficulties in obtaining large uniform domains. The B1 phase was found in P-6-O-PIMB (Fig. 1(a)). A two-dimensional (2D) modulated structure (Col(p2mg)) was proposed for the phase, as shown in Fig. 1(b), based on macroscopic x-ray diffraction. On the other hand, another 2D structure (Col(pm2, m)) shown in Fig. 1(c) has been very recently proposed in the other compound.