Multi-Reference State-Selective Coupled-Cluster Theory

Ludwik Adamowicz得到了理论与计算化学项目的资助，开发了一种量子化学中电子相关的状态选择多参考耦合簇方法。这种方法产生了精确的基态和激发态势能面，包括键的形成和断裂过程。该方法将处理完全活动空间参考函数，结合自旋适应和一阶响应，并通过高效的生产代码执行。此外，新方法的几个应用将被追求，包括核酸碱基，碳团簇和硅团簇的光物理学。理论化学的主要目标之一是计算分子激发态的势能面，以足够的精度描述键断裂和形成等转变的动力学。激发态过程在光化学中起着重要作用，因此与天体物理学以及紫外线诱导的核酸反应有关。

Ludwik Adamowicz is supported by a grant from the Theoretical and Computational Chemistry Program to develop a state-selective multireference coupled-cluster approach to electron correlation in quantum chemistry. This method produces accurate potential energy surfaces of both ground and excited states, including bond making and breaking processes. This method will handle complete-active-space reference functions, incorporate spin adaptation and first-order response, and execute via an efficient production code. Additionally, several applications of the new methodology will be pursued, including the photophysics of nucleic acid bases, carbon clusters, and silicon clusters. One of the major goals of theoretical chemisty is the computation of potential energy surfaces of molecular excited states, of sufficient accuracy to describe the dynamics of transformations such as bond breakage and formation. Excited state processes play a major role in photochemistry, and thus have relevance in astrophysics as well as ultraviolet-induced reactions of nucleic acids.