Applying Density-Functional Theory to Large Molecules: Theoretical and Computational Development

在化学部理论与计算化学项目的资助下，杨教授将基于密度泛函理论开发计算大分子电子结构的理论和计算方法。他将沿着以下两个方向扩展最近的进展：(1)不使用分子轨道的电子密度的直接计算将由新开发的“分而治之”算法进行。该方法将分子划分为子系统，并确定总电子密度和总能量为各子系统贡献的总和。此外，它非常适合并行计算。将努力在大规模并行计算机上实现该理论，每个处理器处理一个子系统。(2)将利用局部投影法开发一种更有效的实现Kohn-Sham密度泛函方程解的方法。在这个项目中开发的新算法将提高密度泛函理论的预测能力，并将使传统方法无法实现的复杂化学和生物现象的理论研究成为可能方法。

With this grant in the Theoretical and Computational Chemistry Program of the Chemistry Division, Professor Yang will develop theoretical and computational methods for computing the electronic structure of large molecules based on density functional theory. He will extend recent progress along the following two directions: (1) The direct calculation of electron density without using molecular orbitals will be undertaken by a newly developed "divide and conquer" algorithm. This method divides the molecule into subsystems and determines the total electron density and energy as the sum of all subsystem contributions. It is, in addition, well-suited for parallel computation. Effort will be made to implement the theory on massively parallel computers, with each processor handling one subsystem. (2) A more efficient way of implementing the solution of the Kohn-Sham density functional equations will be developed by making use of a local projection method. %%% The new algorithms which will be developed in this project will enhance the predictive power of density functional theory and will make possible theoretical studies of complex chemical and biological phenomena that are otherwise impossible by conventional methods.