Quantum State Resolved Dynamics of Surface Reactions

新墨西哥大学的Hua Guo获得了化学学部化学理论、模型和计算方法项目的资助，他开发和应用了最先进的理论方法来研究发生在气体分子和金属催化剂之间界面的重要基本反应的动力学。这种反应在现代社会中发挥着越来越重要的作用。生产氨的博世-哈伯法、汽车催化转化器、微芯片制造和天然气蒸汽重整制氢都是一些著名的例子。然而，我们对界面反应的机理和动力学的理解仍然有限。这主要是因为我们对分子水平上的基本过程缺乏了解。更好地了解这些基本过程不仅可以丰富我们的知识，而且可能有助于设计新的更高效的催化剂和更好地控制催化反应。参与本研究的有本科生、研究生和博士后。具体而言，本提案旨在利用最先进的理论模型和为这些过程开发的工具，透彻理解表面反应（如解离化学吸附和eley - ideal反应）的量子态分解动力学。在前一个资助期取得的突破的基础上，目前的研究计划侧重于基于大量密度泛函数理论点准确确定气相物质与金属表面相互作用的全维Born-Oppenheimer势能面，并对这些势能面进行高维量子动力学计算。这些研究代表了对基本表面反应动力学的系统和全面的方法，并有望对多原子体系的能量流动、激活机制以及模式特异性和键选择性的起源提供有价值的启示。在这些研究中获得的见解也可能为控制界面化学的未来策略提供建议。此外，这些高级理论为更近似的动力学模型提供了基准，并有望刺激其他表面反应的理论研究。这项研究产生的计算机代码和势能面将提供给更广泛的社区。

Hua Guo of the University of New Mexico is supported by an award from the Chemical Theory, Models and Computational Methods program in the Chemistry Division to develop and apply state-of-the art theoretical approaches to study the dynamics of important elementary reactions occurring at the interface between gas molecules and metal catalysts. Such reactions play an increasingly important role in modern society. The Bosch-Haber process for producing ammonia, automobile catalytic converters, microchip manufacture, and hydrogen generation from steam reforming of natural gas are a few well-known examples. Yet our understanding of the mechanism and dynamics of interfacial reactions remains limited. This is largely because our lack of knowledge of elementary processes at the molecular level. A better understanding of these elementary processes will not only enrich our knowledge, but might also help the design of new and more efficient catalyst and better control of the catalytic reactions. Undergraduate, graduate students and postdoctoral associates participate in this research. Specifically, this proposal aims at a thorough understanding of quantum state resolved dynamics of surface reactions such as dissociative chemisorption and Eley-Rideal reactions, using state-of-the-art theoretical models and tools developed for these processes. Building on breakthroughs achieved in the previous funding period, the current research program focuses on the accurate determination of full-dimensional Born-Oppenheimer potential energy surfaces for the interaction of gas phase species with metal surfaces based on large numbers of density functional theory points, and high-dimensional quantum dynamics calculations on these potential energy surfaces. These studies represent a systematic and comprehensive approach to fundamental surface reaction dynamics and are expected to shed valuable light on the energy flow in the polyatomic system, activation mechanism, and the origin of the mode specificity and bond selectivity. Insights gained in these studies may also suggest future strategies to control interfacial chemistry. In addition, these high-level theories offer benchmarks for more approximate dynamic models and are expected to stimulate theoretical studies of other surface reactions. The computer codes and potential energy surfaces resulting from this research will be available to the broader community.