Time-Dependent Properties and Real-Time Dynamics from Quasiclassical Quantum Simulations of Complex Systems

主要目标是开发，测试和应用新的从头计算模拟方法，允许生成和/或分析（基于实时的属性）复杂分子多体系统的近似量子动力学在10-100个原子的范围内。目的是从量子模拟中提取准经典光谱信息，如红外光谱和散射函数S（Q，ω）。所选择的方法是必不可少的量子统计力学的路径积分公式和从头算分子动力学技术方面的实施。特别是，基于费曼的路径质心坐标的形式主义将利用计算方案。此外，各种现有的量子校正方案将分析在质心的概念，它是希望也可以设计基于此分析的新方案。在应用方面，既包括有限系统如“软分子”和“量子簇”，也包括凝聚态系统如水和冰。

The principle goal is to develop, test and apply novel ab initio simulation methods that allow to generate and/or analyze (in term of real-time-based properties) approximate quantum dynamics for complex molecular many-body systems in range of 10-100 atoms. The aim is to extract quasiclassical spectral information such as infrared spectra and scattering functions S(Q,omega) from quantum simulations. Essential to the chosen approach is the path integral formulation of quantum statistical mechanics and its implementation in terms of ab initio molecular dynamics techniques. In particular, the formalism based on Feynman's path centroid coordinate will be exploited in terms of computational schemes. In addition, various existing quantum correction schemes will be analyzed in terms of centroid concept and it is hoped that novel schemes can also be devised based on this analysis. Concerning applictions, both finite systems such as "floppy molecules" and "quantum clusters" and condensed matter systems such as water and ice will be covered.