New Methods for Incorporating Quantum Mechanics in the Treatment of Complex Reactive Dynamical Systems

明尼苏达大学双城分校的Donald Truhlar获得了理论，模型和计算方法计划的奖励，以开发用于模拟化学中复杂反应动力系统的方法，并将这些方法应用于不同的系统。研究的一个重点是开发将量子力学效应纳入复杂系统的技术。研究的一个关键问题是电子结构理论和动力学的接口。PI和他的研究小组正在开发有效计算的新方法 势能面和耦合项的方式，是实际的复杂的模拟。他们正在设计许多新的方法，包括联合收割机结合量子力学和分子力学的新方法，用于光诱导过程动力学计算的电子态非绝热表示的新方法，计算耦合态动力学中核运动的新方法，拟合耦合势能面的新方法，以及模拟酶或其他环境坐标参与反应坐标的新方法。本研究的长期目标包括（i）计算光化学反应的分支比，（ii）大气成核过程的模拟和（iii）酶催化反应的速率常数、动力学同位素效应和速率常数的温度依赖性的计算。这些研究领域具有巨大的技术重要性，特别是对健康，环境，社会的物质需求，工业竞争力和国防

Donald Truhlar of the University of Minnesota- Twin Cities is supported by an award from the Theory, Models and Computational Methods program to develop methods for simulating complex, reactive dynamical systems in chemistry and for applying these methods to diverse systems. A focus of the research is the development of techniques to incorporate quantum mechanical effects in complex system. A key issue that the research addresses is the interface of electronic structure theory and dynamics. The PI and his research group are developing new approaches for efficiently computing potential energy surfaces and coupling terms in a manner that is practical for complex simulations. They are devising many novel methods including new ways to combine quantum mechanics and molecular mechanics, new methods for the diabatic representation of electronic states for use in dynamics calculations on photo-induced processes, new approaches to calculating the nuclear motion in coupled-state dynamics, new approaches to fitting coupled potential energy surfaces, and novel ways to model the participation of enzyme or other environmental coordinates in the reaction coordinate.The long range objectives of this research involve (i) calculation of branching ratios for photochemical reactions, (ii) simulation of atmospheric nucleation processes and (iii) calculation of the rate constants, kinetic isotope effects, and temperature dependence of the rate constants for reactions catalyzed by enzymes. These research areas are of enormous technological importance especially for health, the environment, the material needs of society, industrial competitiveness and defense