RUI: Innovative Simulations to Study Pressure Effects on Fundamental Gas-Phase Chemical Processes

在化学系化学结构、动力学和机理a （CSDM-A）项目的支持下，菲里斯州立大学的Luis Rivera教授正在开发计算方法来研究压力对气相基本化学动力学过程的影响。相互竞争的化学动力学过程，如能量传递、异构化和离解，在高压碰撞状态下还没有得到很好的理解。目前的计算方法在研究高压碰撞下的振动能量松弛和反应动力学方面存在精度和计算成本方面的局限性。Rivera教授和他的学生将应用规范方法来开发分子动力学模拟，这些模拟高度精确，计算成本低，更重要的是，更广泛地适用于凝聚相动力学。他们的研究可以更好地理解高压和高温极端条件下的基本化学动力学过程，这是目前理论和实验方法难以实现的挑战。计划与中学生开展的外展活动将培养和激励下一代青年学者和科学家。理解分子内部和分子之间振动能量传递的机制是理解许多物理和化学过程的基础。芮项目的目标是了解气相基本化学动力学过程，如高压碰撞状态下的能量传递、异构化和解离。该项目还将通过应用规范方法来解决产生精确势能面（PESs）的有效方法的需求。规范方法表明，对于一类分子，它们的PESs具有相同的形状。在pps上出现的不同形状是缩放的问题。规范方法将允许计算廉价和高度精确的分子动力学模拟，这对于研究基本的化学动力学过程是必不可少的。从这个项目中获得的见解将使我们更接近于统一气相和凝析相化学过程的模型。这项工作的结果将对碰撞能量转移和孤立二元碰撞近似失效的化学反应有一个基本的理解。这个项目对菲里斯州立大学的本科生来说是一个独特的研究机会。研究是提供成长、发展和培训的本科教育的重要组成部分。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

With support from the Chemical Structure, Dynamics, and Mechanisms-A (CSDM-A) program in the Division of Chemistry, Professor Luis Rivera of Ferris State University is developing computational approaches to study pressure effects on gas-phase fundamental chemical dynamics processes. Competing chemical dynamics processes such as energy transfer, isomerization, and dissociation are not well understood in the high-pressure collisional regime. Current computational methods have limitations in terms of accuracy and computational cost for studying vibrational energy relaxation and reaction dynamics in the high-pressure collisional regime. Professor Rivera and his students will apply canonical approaches to develop molecular dynamics simulations that are highly accurate, computationally inexpensive, and, more importantly, with broader applicability to condensed phase dynamics. Their studies could lead to a better understanding of fundamental chemical dynamics processes under extreme conditions of high pressure and temperature, which is otherwise a challenge to achieve by current theoretical and experimental methods. The intended outreach activities with middle school students will prepare and inspire the next generation of young scholars and scientists.Understanding the mechanisms of vibrational energy transfer within and among molecules is fundamental to understanding many physical and chemical processes. The goal of this RUI project is to understand gas-phase fundamental chemical dynamics processes, such as energy transfer, isomerization, and dissociation in the high-pressure collisional regime. This project will also address the need for efficient approaches for generating accurate potential energy surfaces (PESs) by application of canonical approaches. Canonical approaches demonstrate that for a class of molecules, their PESs have the same shape. What appears to be different shapes on the PESs is a matter of scaling. Canonical approaches will allow for computationally inexpensive and highly accurate molecular dynamics simulations, which are essential to study fundamental chemical dynamics processes. The insights gained from this project will take us a step closer to unifying models for gas and condensed-phase chemical processes. The outcomes of this work will give a fundamental understanding of the collisional energy transfer and chemical reactions where the isolated binary collision approximation breaks down. This project is a unique research opportunity for undergraduate students at Ferris State University. Research is an essential part of undergraduate education that provides growth, development, and training.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.