Nonadiabatic and quantum effects in chemical dynamics

米勒德亚历山大是由化学理论，模型和计算方法计划在化学部门奖的支持，使用量子力学研究如何涉及分子自由基的化学反应发生在多个势能面（PES的），特别关注广泛的实验兴趣的基本反应。亚历山大和同事开发的独特方法对于解释和挑战正在进行的实验研究至关重要。这些方法提供了一个最有利的方式来进行高度准确的状态到状态的化学反应的动力学计算，涉及多个PES的。亚历山大正在扩展这种方法来模拟更复杂的开壳层系统的动力学，并开发新的量子力学有限元为基础的方法来处理碰撞动力学和可视化的结果，描绘的空间行为的波函数反应碰撞和空间演化的量子模拟的化学反应如何“流”的势能面。另一个研究项目的重点是碰撞伙伴的临时捕获如何在量子中表现出来？共振？这可以通过涉及冷原子碰撞的新实验来探测。分子自由基在许多化学环境中起着关键作用，包括燃烧、推进、材料加工、等离子体和修复化学。亚历山大的研究为理解最近的实验结果以及大气、星际气体云和冷化学中的重要化学过程提供了基础。亚历山大集团免费分发计算机代码和先进的教学模块在碰撞动力学和量子化学。

Millard Alexander is supported by an award from the Chemical Theory, Models and Computational Methods program in the chemistry division to use quantum mechanics to investigate how chemical reactions involving molecular free radicals occur on multiple potential energy surfaces (PES's), with a particular focus on elementary reactions of wide experimental interest. The unique methodology developed by Alexander and coworkers is crucial for interpreting and challenging ongoing experimental investigations. These methods provide one of the most advantageous ways to carry out highly accurate state-to-state calculations on the dynamics of chemical reactions involving multiple PES's. Alexander is extending this approach to simulate the dynamics of more complex open-shell systems and also developing novel quantum mechanical finite-element based approaches to treat the collision dynamics and visualize the results, portraying the spatial behavior of the wavefunctions for reactive collisions and the spatial evolution of the quantum analogue of how a chemical reaction "flows" over a potential energy surface. Another research project focuses on how temporary trapping of collision partners manifests itself in quantum ?resonances?, which can be probed by novel experiments involving collisions of cold atoms. Molecular free radicals play a key role in many chemical environments, including combustion, propulsion, materials processing, plasmas, and remediation chemistry. Alexander's research provides a foundation for understanding the results of recent experiments, as well as important chemical processes in the atmosphere, interstellar gas clouds and cold chemistry. The Alexander group freely distributes computer codes and advanced instructional modules in collision dynamics and quantum chemistry.