Excluded Volume and Electrostatic Interactions in Liquid Crystals

排除液晶中的体积和静电相互作用

• 批准号: 0501262
• 负责人: Edward Samulski
• 金额: --
• 依托单位: University of North Carolina at Chapel Hill
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-06-15 至 2011-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0501262&HistoricalAwards=false
• 关键词: Excluded; Volume; Electrostatic; Interactions; Liquid

This project employs iterative synthetic chemistry in combination with physicochemical characterization (emphasizing nuclear magnetic resonance) to target novel liquid crystal phase symmetries, e.g., biaxial and polar nematic phases, with a goal of delineating the underlying molecular physics. Additionally, the new molecular structures created in this project may point to Liquid Crystal Display (LCD) materials that exhibit more facile electro-optic switching. While the research focus herein is on liquid crystals, these anisotropic fluids may be viewed more generally as an entre to better comprehension of subtle intermolecular interactions in ordinary liquids. Undergraduates (with summer research support) and graduate students are exposed to rigorous training in contemporary synthesis and physical chemistry. Moreover the subject matter is intriguing as well as applicable, and the training enables graduates to pursue a career in the important area of display technologies. Structure-property relations in liquid crystals continue to be a very fertile area for understanding fundamental interactions in soft materials and their associated applications such as Liquid Crystal Displays (LCD)s. In liquids molecular shape considerations-excluded volume interactions-dominate the dynamic, short-range packing, and in some fluids these interactions propagate over mesoscopic scales giving rise to long-range orientational order-the signature of thermotropic liquid crystals. But electrostatic interactions are responsible for condensed phases generally. And in fact, it is the delicate combination of both repulsive and attractive interactions that enable molecules with extreme shapes (rod-like and disc-like) to assemble into a variety of fluid architectures: uniaxial nematics, stratified smectics, columnar discotic phases, and the recently-discovered "banana phases" exhibited by nonlinear molecules. An explosion of Liquid Crystal Displays (LCD)s-a glass "sandwich" whose pixels encapsulate a curious state of matter-has transformed both the desktop and the battlefield in the last decade. LCDs have made images accessible in all areas of science, technology, medicine, government, commerce, and entertainment. Remote imaging makes graphical tracking of severe weather immediately available. It gives physicians an opportunity to "see" patients and monitor intricate medical procedures. Low-cost LCDs make the web accessible in undeveloped countries and LC projectors are essential to high-tech teaching and corporate communications. Chances are that you are reading an electronic version of this abstract on a LCD! We are researching the essential component of these displays, liquid crystal molecules that show electric-field-activated optical properties. Our ultimate goal is to enable a new generation of physical scientists to design new liquid crystals that will continue what the first generation of LCDs did for watches, computers, and cell phones. We anticipate that the new molecules created in our program will lead to more robust LCD materials which in turn, exhibit faster electro-optic switching. In our program undergraduates, vying for competitive summer research support, and graduate students in chemistry and material science are exposed to rigorous training in synthetic and physical chemistry in a subject that is intriguing as well as applicable. The training is designed to enable graduates to pursue a career in the technologically important area of electro-optic displays.

该项目采用迭代合成化学与物理化学表征（强调核磁共振）结合使用，以靶向新型的液晶相对称性，例如双轴和极性列列相，以及划定基本分子物理学的目标。 此外，该项目中创建的新分子结构可能指向液晶显示器（LCD）材料，这些材料表现出更容易的电形开关。 尽管这里的研究重点是液晶，但这些各向异性流体可能会更普遍地视为更好地理解普通液体中微分分子间相互作用的群体。 本科生（夏季研究支持）和研究生接受了当代合成和物理化学方面的严格培训。 此外，主题既有趣又适用，培训使毕业生能够在展示技术的重要领域从事职业。 液晶中的结构特性关系仍然是了解软材料及其相关应用（例如液晶显示器（LCD））的基本相互作用的非常肥沃的领域。 在液体中，分子形状因素考虑的体积相互作用赋予动态，短距离堆积，在某些流体中，这些相互作用在介观尺度上传播，从而引起了远距离定向顺序 - 嗜热液晶的特征。 但是静电相互作用通常负责凝结阶段。 实际上，正是排斥性和有吸引力的相互作用的精致组合，使分子具有极端形状（类似杆状的和圆盘状），以组装成各种流体体系结构：单轴神经术，分层示威，柱状盘状相位，柱状盘状相，以及最近被证明的“ Banana阶段”均表现出非线性的“ Banana阶段”。 液晶显示器（LCD）S-a玻璃“三明治”的爆炸爆炸，其像素封装了一个好奇的物质状态，在过去的十年中改变了台式机和战场。 LCD使在科学，技术，医学，政府，商业和娱乐领域的所有领域都可以访问图像。 远程成像使得立即对恶劣天气进行图形跟踪。 它为医生提供了“查看”患者并监控复杂医疗程序的机会。低成本的LCD使该网络在未开发国家 /地区可以访问，LC投影仪对于高科技教学和企业通信至关重要。 您可能正在阅读LCD上此摘要的电子版本！ 我们正在研究这些显示的基本成分，即显示电场激活光学特性的液晶分子。 我们的最终目标是使新一代的物理科学家设计新的液晶，以继续第一代LCD为手表，计算机和手机所做的事情。 我们预计我们程序中创建的新分子将导致更强大的LCD材料，从而表现出更快的电形转换。 在我们的计划的本科生中，争夺具有竞争力的夏季研究支持，化学和材料科学领域的研究生在一个有趣且适用的学科中，接受了对合成和物理化学的严格培训。 该培训旨在使毕业生能够从事电子音乐展示的技术重要领域的职业。