Improved Methods for Including Vibronic and Environmental Effects in Simulations of Optical Spectroscopy

加州大学默塞德分校的克里斯汀·伊斯伯恩教授得到了化学部化学理论、模型和计算方法项目的支持，以开发和应用改进的方法来模拟光学光谱。她的研究重点是生色团(光吸收体)周围的环境(如溶剂、表面、蛋白质)如何影响电子激发态。新的模拟技术将被开发出来，以更好地表示原子和实验细节。在复杂环境中模拟光学光谱的新方法可以用于指导具有所需光学性质的新分子和材料的设计。改进的光学光谱学模拟工具将提高对复杂环境中电子激发过程的理解，并有可能推动光伏、电光或光催化领域的新技术。伊斯伯恩教授还参与了更广泛的高中、本科生和研究生层面的影响活动。为了服务于主要的第一代学生群体，本科生制作了英语和学生母语的短视频，他们用这些视频讨论他们的经历。为期一周的研究生水平暑期班专注于计算机理论的基础和应用，有助于为未来的劳动力培养下一代化学家。光学光谱学，包括光学吸收光谱、荧光光谱和时间分辨超快电子光谱，是探测许多化学体系和分子反应的电子行为的最常用的技术。这些方法对环境效应很敏感，然而，在复杂环境中模拟分子光谱的传统方法往往由于缺乏振动效应和/或缺少分子与环境之间的特定相互作用而无法再现光谱形状。伊斯伯恩教授和她的团队正在开发一系列方法来模拟光学吸收、荧光和超快光谱，这些方法通过计算原子环境中的地面和激发振动模式来解释振动跃迁和特定的溶质-溶剂-环境相互作用。他们正在研究环境如何影响复杂环境中各种发色团的光谱形状和电子弛豫。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Professor Christine Isborn of the University of California Merced is supported by an award from the Chemical Theory, Models and Computational Methods program in the Division of Chemistry to develop and apply improved methods for simulating optical spectroscopy. Her research focuses on how the environment (e.g. solvent, surface, protein) surrounding a chromophore (light absorber) affects the electronic excited states. New simulation techniques will be developed that better represent atomistic and experimental details.The new methods for simulating optical spectroscopy in complex environments can be used to guide the design of new molecules and materials that have desired optical properties. Improved tools for simulating optical spectroscopy will improve understanding of electronic excitation processes in complex environments, with the potential for this increased understanding to drive new technologies in the fields of photovoltaics, electro-optics, or photo-catalysis. Professor Isborn also engages in broader impact activities at the high school, undergraduate, and graduate student levels. To serve a primarily first-generation student population, undergraduate students create short videos in both English and the student’s native language in which they discuss their experiences. A week-long graduate student level summer school focused on the fundamentals and applications of computer theory helps to train the next generation of chemists for the workforce of the future. Optical spectroscopy, including optical absorption, fluorescence, and time-resolved ultrafast electronic spectroscopy, is the most commonly used technique for probing the electronic behavior of many chemical systems and molecular reactions. These methods are sensitive to environmental effects, however, traditional approaches for modeling optical spectra of molecules in complex environments often fail to reproduce spectral shapes due to either lacking vibronic effects and/or missing specific interactions between the molecule and its environment. Professor Isborn and her group are developing a family of approaches for simulating optical absorption, fluorescence, and ultrafast spectra that account for both vibronic transitions and specific solute-solvent-environment interactions by computing ground and excited vibrational modes in the presence of the atomistic environment. They are examining how the environment affects spectral shapes and electronic relaxation for a variety of chromophores within complex environments.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.