Semiclassical Molecular Dynamics in Extended Systems

扩展系统中的半经典分子动力学

• 批准号: 9725462
• 负责人: Vartkess Apkarian
• 金额: $ 32.57万
• 依托单位: University of California-Irvine
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-02-01 至 2001-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9725462&HistoricalAwards=false
• 关键词: Semiclassical; Molecular; Dynamics; Extended; Systems

V. Ara Apkarian is suported by a grant from the Theoretical and Computational Chemistry Program to perform semiclassical molecular dynamics simulations of quantum dynamic effects in extended systems. This approach has already been developed and employed successfully for gas-phase spectroscopy. The methodology is now being applied to the spectroscopy of cryogenic solids, condensed hydrogen, and hydrogen-bonded networks, as well as room-temperature liquid resonance-Raman and photon-echo spectroscopies. Quantum effects are simulated with a `black box` dependent only on inputted potential energy parameters. Due to the many degrees of freedom in these applications, the computations are very intensive. This is partially remedied by relying on short-time propagation with wavefunction reconstruction through repeated Monte Carlo sampling. In order to understand quantum dynamics in systems of large dimensionality, such as liquids and solids, new simulation methods are needed. In condensed phase spectroscopy in particular, connecting observables to the underlying molecular structures and their motions currently relies on approximate techniques. Theoretical developments that aim toward a microscopic understanding of condensed phase spectra are invaluable tools in the interpretation and design of experiments.

V. Ara Apkarian得到了理论和计算化学计划的资助，在扩展系统中进行量子动力学效应的半经典分子动力学模拟。这种方法已经被开发并成功地应用于气相光谱。该方法现在被应用于低温固体、凝聚氢和氢键网络的光谱学，以及室温液体共振拉曼光谱和光子回声光谱。量子效应是用一个只依赖于输入势能参数的“黑盒”来模拟的。由于在这些应用中有许多自由度，计算是非常密集的。通过重复蒙特卡罗采样，依靠波函数重建的短时传播，可以部分地弥补这一点。为了理解诸如液体和固体等大维度系统中的量子动力学，需要新的模拟方法。特别是在凝聚相光谱中，将可观测物与潜在的分子结构及其运动联系起来目前依赖于近似技术。旨在微观理解凝聚相光谱的理论发展是解释和设计实验的宝贵工具。