Conformation Analysis of Ferroelectric Liquid Crystals

点击翻译按钮获取中文摘要

In this study, we have carried out experimental and theoretical conformational analyzes of ferroelectric liquid crystals (FLC) in order to understand the origin of ferroelectricity and the structure-property relationship in this novel class of liquid crystalline molecules.1. we have synthesized a FLC sample with selectively deuterated chiral alkyl chain and performed deuterium NMR study. The results are analyzed by molecular orbital (MO) calculations to give the average chiral-chain conformation in liquid crystalline phases.2. Molecular orbital (MO) calculation and molecular dynamics (MD) simulation have been carried out for an antiferroelectric liquid crystalline molecule MHPOBC to understand its conformational property and the origin of bent structure formation in crystalline phase. This analysis concludes that 1) the essential conformational feature of the chiral chain of MHPOBC is determined by intramolecular interactions, 2) MHPOBC can adopt two major conformations, i.e., linear and bent conformations, and 3) the bent conformation is selected in the crystalline phase as a consequence of intermolecular steric interactions.3. We also carried out a series of Monte Carlo (MC) simulations of model liquid-crystalline molecules (including beads and Gay-Berne model molecules). These studies have provided us with a straightforward insight into the molecular mechanism of the spontaneous formation of liquid crystalline order.