CAREER: Accelerated Chemical Reactions in Unique Solvation Environments

在化学系化学理论、模型和计算方法项目的支持下，乔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下化学反应的加速。开发新的化学物质以解决广泛的社会应用需要对化学反应的速率有基本的了解，在某些情况下，化学反应可以通过界面的存在或在小液滴中限制反应物而大大加速。在所有情况下，反应加速都是通过原子尺度上的相互作用发生的，使用高性能计算机的分子模拟通常用于表征反应机制。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下速率加速的新框架。该项目旨在提高对界面和异相溶剂化环境中重要的C-C键形成反应和果糖和多醇转化的催化速率增强的机理理解。这有可能使量身定制的反应环境设计（如微滴，薄膜），以优化反应速率/产率。McDaniel团队将与地区高中教师合作，更好地将软件和数据科学工具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、薄膜和其他非均相溶剂化环境中，有许多显著加速化学反应的引人注目的例子。在所有情况下，关键问题涉及微观机制和原子相互作用，通过这些反应在这些独特的环境中加速。Jesse McDaniel和他的研究小组将通过开发一种新的计算框架来研究这些催化机制，该框架用于计算复杂环境下的化学反应自由能分布。新方法将包括具有精确远程静电嵌入的量子力学/分子力学（QM/MM），以及基于物理的/神经网络（PB/NN）反应力场。这两种方法都将在统一的软件基础设施中实现，以同时优化精度和采样。McDaniel小组将应用这一新的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，以及微滴中的加速Friedel-Crafts烷基化。这些努力有可能为加速化学反应提供详细的微观理解。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值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.