Theoretical Studies of Kinetics, Dynamics and Mechanisms of Polyatomic Bimolecular Gas Phase Chemical Reactions

理论和计算化学计划支持 犹他州大学的张教授说。 对该区域进行的研究 未来三年涉及新的直接开发和应用 研究势能面，动力学， 和气相双分子反应动力学。 动力学方法是 基于变分过渡态理论， 多维半经典隧穿修正 反应路径信息将直接从足够准确的从头算或非本地 密度泛函方法，从而避免了构建 分析潜在的功能，目前不存在的大部分 正在考虑的反应。 振动状态的计算方法 还将制定选定的费率。 这些新的方法将被用来研究详细的动态， 一些激进的反应。 考虑中的大多数反应涉及 通过与H2反应的羟基自由基等物质的夺氢，或 甲烷 在这些调查中将特别注意 试剂振动能对计算的双分子反应速率的影响。 这些调查还将试图将 对这些反应的动力学和机制的理解在基础和技术两个层面都有影响。 在 从技术上讲，这些氢提取反应具有重要意义， 燃烧、环境和大气化学。 用一个 基本化学理解，这些反应包含类似的反应 简单轻-轻-重（L-L-H）和重-轻-重（H-L-H）运动学 原子-硅藻反应，其动力学已被充分研究。 这些反应的实验正在不同的实验室进行。 因此，潜在 从这项工作中获得的能量表面信息将有助于 对新的实验观察的解释。

The Theoretical and Computational Chemistry program is supporting professor Truong at the University of Utah. The research to be conducted over the next three years involves the development and applications of new direct ab-initio dynamics methods for investigating potential energy surfaces, kinetics, and dynamics of gas-phase bimolecular reactions. The dynamical method is based on Variational Transition State Theory augmented with several multidimensional semiclassical tunneling corrections. Reaction path information will be evaluated directly from a sufficiently accurate ab-initio or non-local density functional method, thus obviating the need for the construction of analytical potential functions which currently do not exist for most of the reactions under consideration. A methodology for calculating vibrational-state selected rates will also be developed. These new methods will be used to study the detailed dynamics of a number of radical reactions. Most of the reactions under consideration involve hydrogen abstraction by species such as hydroxyl radical reacting with H2, or methane. Particular attention will be devoted in these investigations to the effect of reagent vibrational energy on the computed bimolecular reaction rates. These investigations will also attempt to correlate the topology of the potential An understanding of the dynamics and mechanisms of these reactions has implications at both the fundamental as well as technological levels. In terms of technology, these hydrogen abstraction reactions are of significance in combustion, environmental and atmospheric chemistry. In terms of a fundamental chemical understanding, these reactions contain similar reaction kinematics with simple light-light-heavy (L-L-H) and heavy-light-heavy (H-L-H) atom-diatom reactions whose dynamics have been well studied. Experiments on these reactions are underway in different laboratories. Hence, potential energy surface information resulting from this work will be valuable in aiding the interpretations of new experimental observations.