Development of Semi-Classical Methods for Treating Quantum Dynamics in Condensed Phase Systems

处理凝聚相系统中量子动力学的半经典方法的发展

• 批准号: 9978320
• 负责人: David Coker
• 金额: $ 36.8万
• 依托单位: Trustees of Boston University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-12-01 至 2002-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9978320&HistoricalAwards=false
• 关键词: Development; Semi; Classical; Methods; Treating

David Coker is supported by a grant from the Theoretical and Computational Chemistry Program to continue his research on the development of semiclassical methods for treating quantum dynamics in condensed phase systems. New methods for computing real time correlation functions in condensed phase quantum systems based on semiclassical expressions for the propagator will be developed and applied to model solution phase systems where nuclear interference and tunneling effects play a crucial role in determining spectroscopy, transport and other dynamical solute properties in solution. The semiclassical approach employs a propagator method using a swarm of weighted classical trajectories, each multiplied by a phase factor. The time correlation function contains two of these propagators and thus includes interference effects between pairs of phase weighted classical trajectories. Combined nonadiabatic MD and semiempirical electronic structure methods will be extended to study photodissociation and geminate recombination dynamics of triiodide anion in solution. Quantal interference effects in the intramolecular vibrations of this molecule in solution will be explored with this new semiclassical approach.Since most industrial synthetic processes occur in solution, it is important to gain an increased understanding of the influence that solvent has on fundamental chemical processes in solvated systems including molecular transport, proton transfer, and electronic excitation. This theoretical research will lead to an improved understanding of the factors which influence chemical reactions in solution.

大卫科克是由理论和计算化学计划的资助，继续他的研究发展的半经典方法治疗凝聚相系统中的量子动力学。 新的方法计算真实的时间相关函数在凝聚相量子系统的传播子的半经典表达式的基础上，将开发和应用到模型的解决方案相系统中的核干涉和隧道效应发挥了至关重要的作用，在确定光谱，运输和其他动态溶质性质的解决方案。 半经典的方法采用传播子方法，使用一群加权的经典轨迹，每个乘以一个相位因子。时间相关函数包含这些传播子中的两个，因此包括相位加权经典轨迹对之间的干扰效应。 结合非绝热分子动力学和半经验电子结构方法将被扩展到研究溶液中三碘负离子的光解和成对复合动力学。由于大多数工业合成过程都发生在溶液中，因此，重要的是要增加溶剂对溶剂化体系中基本化学过程的影响，包括分子输运、质子转移和电子激发。 这一理论研究将导致对影响溶液中化学反应的因素的更好的理解。