CAREER: Accelerated Chemical Reactions in Unique Solvation Environments

在化学系化学理论、模型和计算方法计划的支持下，佐治亚理工学院的杰西·麦克丹尼尔正在研究界面和特定溶剂化环境中化学反应的加速。开发满足广泛社会应用的新化学需要对化学反应的速度有基本的了解，在某些情况下，通过存在界面或将反应物限制在小液滴中，可以大大加快化学反应的速度。在所有情况下，反应加速都是通过原子尺度的相互作用发生的，使用高性能计算机的分子模拟经常被用于表征反应机制。麦克丹尼尔博士和他的研究小组将在这些方法的基础上，开创一个计算和预测复杂环境中的速度加速的新框架。该项目旨在提高对果糖和多元醇在界面和非均相溶剂化环境中重要的C-C键形成反应和转化的催化速率增强的机理的了解。这有可能使量身定制的反应环境(例如微滴、薄膜)设计成为可能，以优化反应速率/产率。McDaniel团队将与地区高中教师合作，将软件和数据科学工具更好地整合到高中教育课程中，并有效地培训下一代计算科学家。在微滴、薄膜和其他异质溶剂化环境中，有许多显著加速化学反应的令人信服的例子。在所有情况下，关键问题都与微观机制和原子相互作用有关，通过这些机制和原子相互作用，反应在这些独特的背景下被加速。杰西·麦克丹尼尔和他的研究小组将通过开发一个新的计算框架来研究这些催化机理，以计算复杂环境中的化学反应自由能分布。新方法将包括具有精确长程静电嵌入的量子力学/分子力学(QM/MM)，以及基于物理/神经网络(PB/NN)的反应力场。这两种方法都将在统一的软件基础设施中实施，以同时优化准确性和抽样。McDaniel小组将应用这一新框架来研究在非均相溶剂化环境中加速化学反应的各种例子，包括薄膜中的Claisen-Schmidt缩合反应、离子液体/水溶液中的果糖转化以及微滴中加速的Friedel-Craft烷基化。这些努力有可能为加速的化学反应提供详细的微观了解。该奖项反映了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。

With support from the Chemical Theory, Models and Computational Methods program in the Division of Chemistry, Jesse McDaniel of the Georgia Institute of Technology is investigating the acceleration of chemical reactions at interfaces and within specific solvation environments. Developing new chemistries that address a wide range of societal applications requires fundmental understanding of the rates of chemical reactions, which in certain cases can be substantially accelerated by the presence of interfaces or confinement of reactants in small droplets. In all cases, reaction acceleration occurs through interactions at the atomic scale, and molecular simulations using high-performance computers are routinely engaged to characterize reaction mechanisms. Dr. McDaniel and his research group will build on these approaches by pioneering a new framework for calculating and predicting rate acceleration in complex environments. The project aims to improve mechanistic understanding of catalytic rate enhancements at interfaces and heterogenous solvation environments for important C-C bond forming reactions and conversions of fructose and polyalcohols. This has the potential to enable tailored design of reaction environments (e.g. microdroplets, thin films) to optimize the reaction rates/yield. The McDaniel team will partner with regional high school teachers to better integrate software and data science tools within the high school educational curriculum and effectively train the next generation of computational scientists.There are many compelling examples of dramatically accelerated chemical reactions in microdroplets, thin films, and other heterogenous solvation environments. In all cases, the key questions concern the microscopic mechanisms and atomistic interactions through which the reactions are accelerated within these unique contexts. Jesse McDaniel and his research group will investigate these catalytic mechanisms by developing a new computational framework for calculating chemical reaction free energy profiles in complex environments. The new approach will include quantum mechanics/molecular mechanics (QM/MM) with exact long-range electrostatic embedding, coupled with physics-based/neural network (PB/NN) reactive force fields. Both methods will be implemented within a unified software infrastructure to simultaneously optimize accuracy and sampling. The McDaniel group will apply this novel framework to investigate a variety of examples of accelerated chemical reactivity in heterogeneous solvation environments including Claisen-Schmidt condensation reactions within thin films, fructose conversion within ionic liquid/water solutions, and accelerated Friedel-Crafts alkylation within microdroplets. These efforts have the potential to provide for a detailed microscopic understanding of the accelerated chemical reactivity.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.