Excluded Volume and Electrostatic Interactions in Liquid Crystals

该项目采用迭代合成化学与物理化学表征（强调核磁共振）相结合，以针对新型液晶相对称性，例如，双轴和极性双相，其目标是描绘潜在的分子物理学。 此外，在这个项目中创建的新分子结构可能指向液晶显示器（LCD）材料，表现出更容易的电光开关。 虽然本文的研究重点是液晶，但这些各向异性流体可以更普遍地被视为更好地理解普通液体中微妙的分子间相互作用的一个入口。 本科生（夏季研究支持）和研究生接触到当代合成和物理化学的严格培训。 此外，该主题是有趣的，以及适用，培训使毕业生能够追求在显示技术的重要领域的职业生涯。 液晶中的结构-性质关系仍然是理解软材料及其相关应用（如液晶显示器（LCD））中的基本相互作用的非常肥沃的领域。 在液体中，分子形状的相互作用排除体积相互作用主导动态，短程包装，并在某些流体中，这些相互作用传播介观尺度引起的长程取向秩序的签名热致液晶。 但静电相互作用通常是凝聚相的原因。 事实上，正是排斥和吸引相互作用的微妙结合，使具有极端形状（棒状和盘状）的分子能够组装成各种流体结构：单轴向列相、分层近晶相、柱状分散相以及最近发现的非线性分子所表现出的“香蕉相”。 液晶显示器（LCD）是一种玻璃“三明治”，其像素封装了一种奇怪的物质状态，在过去的十年里，它的爆炸式发展改变了桌面和战场。 LCD使图像在科学、技术、医学、政府、商业和娱乐的所有领域都可以访问。 远程成像使恶劣天气的图形跟踪立即可用。 它使医生有机会“看”病人和监测复杂的医疗程序。低成本的液晶显示器使不发达国家的网络可以访问，液晶投影机对高科技教学和企业通信至关重要。 很有可能你正在阅读这篇摘要的电子版！ 我们正在研究这些显示器的基本组成部分，即显示电场激活光学特性的液晶分子。 我们的最终目标是让新一代的物理科学家能够设计出新的液晶，延续第一代液晶在手表、电脑和手机上的应用。 我们预计，在我们的计划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光开关。 在我们的计划本科生，争夺竞争激烈的夏季研究支持，在化学和材料科学的研究生接触到合成和物理化学的严格训练，这是有趣的，以及适用的主题。 该培训旨在使毕业生能够在电光显示器的技术重要领域从事职业生涯。

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.