Prediction and Analysis in Electron Propagator Theory

这项分子电子结构理论研究项目得到了美国国家科学基金会理论和计算化学项目的支持。将从头算电子传播子理论(EPT)应用于电离势、电子亲和能及相关性质的计算。将使用从从头算理论的其他领域改编的算法来开发用于EPT计算的改进的计算机代码。其中包括使用直接产生电子排斥积分、密度基组和使用拉普拉斯变换技术消除能量分母来计算大分子的二阶和三阶准粒子和重整化自能。这些方法将在一小群工作站上以并行代码实现。该理论将被应用于多电荷碳团簇阴离子和有机金属自由基。像所有计算分子电子结构的从头算方法一样，电子传播子理论(EPT)是基于量子力学的基本方程。EPT方程为严格计算电子激发能、光谱激发能、电离能和电子亲和能提供了一条更直接的途径。本项目的重点是改进计算方法的发展及其在并行计算机上的实施，特别是在工作站集群上。

This project in molecular electronic structure theory is supported by the NSF Theoretical and Computational chemistry Program. Ab initio electron propagator theory (EPT) is applied to the computation of ionization potentials, electron affinities, and related properties. Improved computer codes for EPT computations will be developed using algorithms adapted from other areas of ab initio theory. These include the computation of second and third-order quasiparticle and renormalized self-energy for large molecules using direct generation of electron-repulsion integrals, density basis sets, and elimination of energy denominators using Laplace transform techniques. These methods will be implemented in parallel code for a small cluster of workstations. The theory will be applied to multiply charged carbon cluster anions and to organometallic radicals. Like all ab initio methods for the calculation of the electronic structure of molecules, electron propagator theory (EPT) is based on the fundamental equations of quantum mechanics. The EPT equations provide a more direct route to the rigorous calculation of electron excitation energies and thus of spectroscopic excitations, ionization energies, and electron affinities. The emphasis in this project is on the development of improved computational methods and their implementation on parallel computers, particularly, on clusters of workstations.