International Collaboration in Chemistry: New First Principles Methods for Nonadiabatic Dynamics

斯坦福大学的Todd Martinez得到化学学部化学理论、模型和计算方法的支持，与英国利兹大学的Dmitry Shalashilin进行合作研究。这是一项国际化学合作（ICC）提案。Shalashilin博士的研究得到了EPSRC的支持。pi和他们的研究小组正在开发和应用新的基于轨迹的方法来描述量子力学动力学。这些方法与从头算分子动力学方法兼容，即利用量子化学技术可以实时计算势能面和非绝热耦合。研究人员正在探索两种这样的方法（多构型Ehrenfest和多产卵），以确定每种方法的优势，以便将它们以一种利用各自优势的方式结合起来。从这项工作中产生的新方法将在AIMS-MolPro代码中实现，并提供给广泛的研究人员。pi将研究图形处理单元（gpu）的使用来加速动态计算。该项目为新一代精确的第一性原理动力学方法提供了基础，这些方法可以结合量子力学效应，如多个电子态之间的非绝热表面交叉和轻核（如质子）的隧穿。这些方法对化学，特别是光化学有广泛的影响。这些方法也将用于解释超快时间分辨泵浦-探针光谱。该项目包括在利兹大学和斯坦福大学之间交换学生（最多一个月的短期停留），从而为参与的研究生提供了一个关于两国学术环境的扩展视野。

Todd Martinez of Stanford University is supported by the Chemical Theory, Models and Computational Methods in the Chemistry Division to engage in collaborative research with Dmitry Shalashilin of the University of Leeds in the UK. This is an International Collaborations in Chemistry (ICC) proposal. Dr. Shalashilin's research is supported by the EPSRC. The PIs and their research groups are developing and applying new trajectory based methods for describing quantum mechanical dynamics. These methods are compatible with ab initio molecular dynamics methods, i.e. the potential energy surfaces and nonadiabatic couplings can be computed on the fly with quantum chemical techniques. Two such methods (multi-configurational Ehrenfest and multiple spawning) are being explored in order to determine the advantages of each so that they may be combined in a way which leverages their respective advantages. The new methodology that emerges from this work will be implemented in the AIMS-MolPro code and made available to a wide range of researchers. The PIs will investigate the use of graphical processing units (GPUs) to accelerate the dynamics calculations. The project provides a foundation for a new generation of accurate first principles dynamics methods that can incorporate quantum mechanical effects such as nonadiabatic surface crossing between multiple electronic states and tunneling of light nuclei such as protons. Such methods have a broad impact on chemistry, especially photochemistry. These methods will also be useful for interpreting ultrafast time-resolved pump-probe spectra. The project involves interchange (for short stays up to a month) of students between Leeds and Stanford, thus providing the involved graduate students with an expanded vista concerning the academic environment in each countryThe Office of International Science and Engineering provides co-funding for this award.