Excluded Volume and Electrostatic Interactions in Liquid Crystals

这个项目将通过精心设计的实验和对实验结果的相关建模来表征和量化液晶中的分子间力。其目的是简单和现实地描述在中间相中起作用的取向和构象偏差，以便可以定制分子结构来放大所需的性质。实验旨在将取向有序分离为其主要组成部分--空间和静电相互作用--从而能够预测液晶的性质。核磁共振将用于研究溶质-液晶溶剂对；将描述基于杂环噻吩环和恶二唑环的新液体结构的合成和评估，以突出静电相互作用在非线性“香蕉形”或“回旋镖”形介元中的作用。这些材料的近晶相可能表现出新的电光性能，新的液晶可以用来测试铁电液晶中自发极化起源的“本征极性”模型。了解新类型液晶的分子结构特征的性质将使合理设计新的致液晶材料，这些材料可以针对特定的应用进行优化，如高对比度、快速开关和高自发极化，有助于改进包括平板显示器在内的一系列器件。

9971143SamulskiThis project will characterize and quantifiy intermolecular forces in liquid crystals through carefully constructed experiments and associated modeling of the experimental findings. The aim is to simply and realistically describe the orientational and conformational biases operative in mesophases so that molecular architectures can be tailored to amplify desireable properties. Experiments are designed to separate orientational ordering into its primary components - steric and electrostatic interactions - to enable the prediction of properties of liquid crystals. Nuclear magnetic resonance will be used to study solute-liquid crystal solvent pairs; the synthesis and evaluation of new liquid structures based on heterocyclic thiophene and oxadiazole rings will be delineated to highlight the role of electrostatic interactions in nonlinear "banana-" or "boomerang-shaped" mesogens. New electro-optic properties may be exhibited by smectic phases of these materials, and the new liquid crystals may be used to test the "indigenous polarity" model of the origins of spontaneous polarization in ferroelectric liquid crystals.%%%Understanding the properties of new classes of liquid crystals in terms of their molecular structural features will enable the rational design of new maesogens that can be optimized for specific applications such as high contrast ratios, rapid switching, and high spontaneous polarization useful for improving a range of devices that include flat-panel displays.