Improved Semiclassical Dynamical Methods and Their Application to Condensed Phase Vibrational Relaxation

改进的半经典动力学方法及其在凝聚相振动弛豫中的应用

• 批准号: 9816040
• 负责人: Michael Herman
• 金额: $ 24.7万
• 依托单位: Tulane University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-01-01 至 2002-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9816040&HistoricalAwards=false
• 关键词: Improved; Semiclassical; Dynamical; Methods; Their

Michael Herman is supported by a grant from the Theoretical and Computational Chemistry Program to continue his development of improved semiclassical dynamical methods for treating vibrational relaxation in condensed phases. A series of studies will be undertaken to improve the accuracy and flexibility of semiclassical propagator methods for systems displaying quantum chaos. Herman has developed new integral conditioning methods that analytically account for the local phase cancellation inherent in semiclassical approaches. Further improvements in the approach will be developed for problems involving transitions between molecular quantum states. Applications involve semiclassical treatments of vibrational energy relaxation in condensed phases and clusters. Systems to be treated include a number of small molecules such as diatomic iodine anion in various solvents and in carbon dioxide clusters.Since most chemical reactions of commercial importance occur in the condensed phase, it is important to understand the effect that solvation has on these processes. The theoretical treatment of such systems is complicated by the large number of degees of freedom involved, and any approach to treating such systems needs to be based on some level of approximation. Herman has developed a semiclassical approach for treating the dynamics of such systems that provides important molecular insights into the influence of solvation.

迈克尔·赫尔曼（Michael Herman）得到了理论和计算化学计划的赠款的支持，该计划继续开发改进的半经典动力学方法，用于治疗凝结阶段中的振动放松。 将进行一系列研究，以提高显示量子混乱的系统的半经典传播方法的准确性和灵活性。 赫尔曼（Herman）开发了新的整体条件方法，可以分析地说明半经典方法中固有的局部相位取消。 对于涉及分子量子状态之间过渡的问题，该方法的进一步改进将开发出来。 应用涉及在凝结相和集群中振动能量松弛的半经典处理。 要处理的系统包括许多小分子，例如各种溶剂和二氧化碳簇中的双原子碘阴离子。由于商业意义的最大化学反应发生在凝聚阶段，因此了解溶剂对这些过程的影响很重要。 涉及大量自由度的理论处理使这种系统的理论处理变得复杂，并且任何处理此类系统的方法都必须基于一定程度的近似程度。 赫尔曼（Herman）开发了一种半经典方法来处理此类系统的动力学，该动力学为溶剂化影响提供了重要的分子见解。