CAREER: First Principles Evaluation of Optical Activity in Solids

堪萨斯大学的Marco Caricato得到了化学部化学理论、模型和计算方法项目的支持，他开发了新的理论模型和相应的计算机软件，以模拟手性固体中光和物质之间的相互作用。该提案由美国国家科学基金会EPSCoR办公室和高级网络基础设施办公室联合资助。手性对象是彼此(例如，左手和右手)的不可重叠的镜像。手性分子在自然界中普遍存在，手性在化学和生物学中有着深远的意义。手性分子具有旋转平面偏振光的能力，被认为是“光学活性的”。尽管从旋光性的第一次发现开始，我们已经研究了两百年，但我们仍然不能理解手性晶体的分子结构和它对光的响应之间的关系。卡里卡托博士的研究通过理论模拟提供了这样更深入的理解。这些理论方法正在计算机代码中实现，这些代码将作为开放源码计算模块提供给社区。这些方法还将被集成到Gauss中，这是一个使用非常广泛、维护良好的量子化学软件包。随着手性材料在催化、分子识别和电子领域的应用日益广泛，这项研究也可能导致材料科学的技术突破。卡里卡托博士的推广项目旨在将计算化学带入堪萨斯州的高中课堂。在这个科技时代，计算机模拟具有巨大的教育潜力，Caricato博士与当地高中教师合作创建的模块为学生提供了积极的学习体验，旨在激发他们对科学的热情，以及他们在STEM学科中进行进一步培训的兴趣。Caricato博士的项目的主要目标是：1)发展真正的第一原理量子力学方法，用于计算扩展系统中的旋光(OR)；2)研究有序光学活性材料的结构-性质关系。固体中旋光张量的测量缺少基于理论模拟的物理解释。这是一个重大的缺点，因为这些测量可以明确地提供整个旋光张量，从而使它们自己能够与计算进行直接比较。这个项目的目的是将密度泛函理论的OR计算的预测能力从分子扩展到超分子尺度。人们正在开发新的定性分析方法，这将有助于揭示光学活性材料中分子内和分子间相互作用方面难以捉摸的结构-性质关系。此外，Caricato博士的方法可以解释和预测ECD光谱，这是表征手性自组装材料的主要工具。因此，该项目有可能对此类材料的表征和设计产生重大影响。由于超分子自组装手性材料在电子学、分子识别、传感和CHI光学开关中的重要性日益增加，Caricato博士的努力可能会为技术进步开辟新的途径。

Marco Caricato, of the University of Kansas is supported by an award from the Chemical Theory, Models and Computational Methods program in the Division of Chemistry to develop new theoretical models and corresponding computer software to simulate the interaction between light and matter in chiral solids. The proposal is jointly funded by the NSF EPSCoR Office and the Office of Advanced Cyberinfrastructure. Chiral objects are non-superimposable mirror images of each other (e.g., left and right hands). Chiral molecules are ubiquitous in nature and chirality has profound implications in chemistry and biology. Chiral molecules have the ability to rotate plane-polarized light and are said to be "optically active". Despite two hundred years of research from the first discovery of optical activity, we are still not able to understand the correlation between the molecular structure of a chiral crystal and its response to light. Dr. Caricato's research provides such deeper understanding through theoretical simulations. The theoretical methods are being implemented in computer codes that will be available to the community as an open source computational module. The methods will also be integrated into Gaussian, a very widely-used and well-maintained quantum chemistry software package. This research may also lead to technological breakthroughs in materials science, as chiral materials are becoming increasingly popular for applications in catalysis, molecular recognition, and electronics. Dr. Caricato's outreach program aims to bring computational chemistry into the high school classroom in Kansas. Computer simulations have enormous educational potential in this technological age, and the modules created by Dr. Caricato in collaboration with local high school teachers provide students with an active learning experience aimed at stimulating their enthusiasm for science and their interest in pursuing further training in STEM disciplines. The main goals of Dr. Caricato's project are: 1) to develop truly first principles quantum mechanical methods for the calculation of optical rotation (OR) in extended systems; 2) to investigate structure-property relations in ordered optically active materials. Measurements of the optical rotation tensor in solids are missing a physical interpretation based on theoretical simulations. This is a significant drawback as these measurements can explicitly provide the entire optical rotation tensor, and thus lend themselves to a direct comparison with calculations. This project aims to extend the predictive power of OR calculations with density functional theory from the molecular to the supramolecular scale. New approaches for qualitative analysis are being developed that will help reveal the elusive structure-property relations in optically active materials, both in terms of intra- and inter-molecular interactions. Moreover, Dr. Caricato's methods allow interpreting and predicting ECD spectra, which are a primary tool for the characterization of chiral self-assembled materials. Therefore, this project has the potential to significantly impact the characterization and design of such materials. Dr. Caricato's efforts may open new avenues for technological advances due to the increasing importance of supramolecular self-assembled chiral materials in electronics, molecular recognition, sensing, and chi optical switching.