Grant for Exploratory Research: Monte Carlo-Gaussian Importance Sampling Evaluation of Real-Time Feynman Path Integrals

理论与计算化学专业 化学部支持大卫教授的研究 霍夫曼在爱荷华州州立大学对量子的新方法 动力学计算 这是一个合作项目， 休斯顿大学的唐纳德·库里教授， 这一努力也得到了该司的支持。 费曼 用路径积分法代替传统的 矩阵乘积、特征值和逆的计算， 随着系统规模的增加而迅速扩展。 高斯重要度 抽样用于在Monte 卡洛积分 我们的目标是使完全量子化成为可能 较大尺寸散射系统的机械处理 比以前可能的。 %%% 量子力学数值精确方法 化学反应过去仅限于 含有不超过三个原子，其中至少一个必须 是氢。 这个项目正在测试一个新的计算 一种有望实现这种计算的技术 在更大的系统上，更一般地说，可以用于研究 其他量子力学碰撞过程。

The Theoretical and Computational Chemistry Program in the Chemistry Division is supporting research by Prof. David Hoffman at Iowa State University on a new approach to quantum dynamics calculations. This is a collaborative project with Professor Donald Kouri of the University of Houston whose effort is also being supported by the Division. The Feynman path integral method is used to replace the customary calculation of matrix products, eigenvalues, and inverses which scale very rapidly with system size. Gaussian importance sampling is used to produce a manageable variance in the Monte Carlo integral. The goal is to make possible fully quantum mechanical treatment of scattering systems of a larger size than previously possible. %%% Numerically exact quantum mechanical methods for analyzing chemical reactions have in the past been limited to systems containing no more than three atoms, at least one of which must be hydrogen. This project is testing a new computational technique which offers promise of permitting such calculations on larger systems and, more generally, can be used in studying other quantum mechanical collisional processes.