Multi-Reference Coupled-Cluster Theory. Theoretical Study on Singly- and Doubly- Charged Elemental Cluster Anions

本项目隶属于化学学部的理论与计算化学项目，有两个重点：第一，发展一种新的多参考耦合簇方法，用于获得原子和分子的相关电子能量和波函数；在碳、硅、镓和砷元素簇的单离子和双离子研究中，这种新方法的计算实现。这些团簇的性质包括它们的结构，它们的稳定和亚稳态光激发，以及它们的光破碎途径。这些团簇可以作为固体半导体系统的模型。目前可用的描述分子电子和几何结构的计算方法需要大量改进，以使它们更准确、更可靠，而且使用起来更便宜。这个项目包含了这样的进步，应用于研究由碳、硅、镓或砷原子组成的气相团簇。

This project in the Theoretical and Computational Chemistry program in the Chemistry Division has two thrusts, first, the development of a new multi-reference coupled-cluster approach for obtaining correlated electronic energies and wave functions for atoms and molecules, and second, the computational implementation of this new approach in the study of mono- and dianions of elemental clusters of the elements carbon, silicon, gallium, and arsenic. The properties of these clusters which are being studied include their structures, their stable and metastable photoexcitations, and their photofragmentation pathways. These clusters may serve as models for solid semiconductor systems. %%% The currently available computational methods for describing the electronic and geometric structures of molecules are in need of considerable improvement to make them both more accurate and reliable as well as cheaper to use. This project involves just such advances, with applications to the study of gas-phase clusters comprised of carbon, silicon, gallium, or arsenic atoms.