Quantum State Resolved Dynamics of Surface Reactions

University Of New Mexico, Albuquerque NM

Investigators

Abstract

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.