RUI: Optical Activity and Light Scattering in High Chiral Liquid Crystals

RUI：高手性液晶中的光学活性和光散射

• 批准号: 8906010
• 负责人: Peter Collings
• 金额: $ 1.6万
• 依托单位: Kenyon College
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1990
• 资助国家: 美国
• 起止时间: 1990-03-15 至 1990-10-01
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8906010&HistoricalAwards=false
• 关键词: RUI; Optical; Activity; Light; Scattering

The objective of this project is to investigate the influence of chirality on phase transitions in liquid crystals through the use of optical activity and light scattering measurements. Previous work has demonstrated that high chirality has a significant effect on the isotropic to liquid crystal phase transition, both increasing the complexity of the pretransitional effects and weakening the transition itself. The project seeks to extend this work by (1) performing similar optical activity experiments in a different liquid crystal system, including measurements at lower chirality in both the isotropic and blue phases, (2) utilizing light scattering as a new probe into the complex fluctuation phenomena which take place near transitons involving chiral phases, and (3) investigating three liquid crystal to liquid crystal transtions in chiral systems (smectic A - smectic C*, chiral nematic - smectic A, and chiral nematic - smectic C*). The same techniques used to study the isotropic to liquid crystal transition should reveal new information about the effect of chirality on these phase transitions.

本项目的目的是通过使用光学活性和光散射测量来研究手性对液晶相变的影响。先前的研究表明，高手性对液晶的各向同性相变有显著的影响，既增加了相变前效应的复杂性，又削弱了相变本身。该项目试图通过(1)在不同的液晶系统中进行类似的光学活性实验，包括在各向同性和蓝色相的低手性下的测量，(2)利用光散射作为一种新的探针，研究发生在涉及手性相的转变附近的复杂波动现象。(3)研究了手性体系中三种液晶到液晶的转变（近晶A -近晶C*、手性向列-近晶A和手性向列-近晶C*）。研究各向同性到液晶转变的相同技术将揭示手性对这些相变影响的新信息。