Quantum State Resolved Dynamics of Surface Reactions

新墨西哥大学的郭华获得了化学系化学理论、模型和计算方法项目的支持，以开发和应用最先进的理论方法来研究气体分子和金属催化剂界面上发生的重要基元反应的动力学。这种反应在现代社会中扮演着越来越重要的角色。生产氨的博世-哈伯工艺、汽车催化转化器、微芯片制造以及天然气蒸汽重整制氢都是几个著名的例子。然而，我们对界面反应的机理和动力学的了解仍然有限。这在很大程度上是因为我们缺乏分子水平上的基本过程知识。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、更有效的催化剂和更好地控制催化反应。本科生、研究生和博士后助理参与了这项研究。具体地说，这一提议旨在通过使用为这些过程开发的最先进的理论模型和工具，彻底理解表面反应的量子态分辨动力学，如解离化学吸附和Eley-R Ideas反应。在上一次资助期间取得突破的基础上，当前的研究计划基于大量密度泛函理论点和这些势能面上的高维量子动力学计算，专注于准确确定气相物种与金属表面相互作用的全维Born-Oppenheimer势能面。这些研究代表了一种系统和全面的基本表面反应动力学方法，有望对多原子体系中的能量流动、活化机制以及模式专一性和键选择性的起源提供有价值的启示。从这些研究中获得的见解也可能为未来控制界面化学的策略提供建议。此外，这些高水平的理论为更接近的动力学模型提供了基准，并有望促进对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.