Weakly-bound and metastable anions: Developments of methods and applications

在这个项目的第一阶段，在大阴离子的理论研究方面取得了实质性的进展。发展了一个新的基于电子传播子理论的大规模并行平台(称为P-RICD-SIGMA)和一个新的复数吸收势，使得亚稳阴离子态的计算不需要人工共振。我们已经证明了所实现的二阶电子传播子方法与高阶耦合团簇方法相比具有非常好的性能。引入并表征了一类新的相关结合阴离子。发现了一种新的协同基元反应机理，称为催化电子断键(BBCE)。新开发的方法和程序已成为计算弱结合和亚稳态阴离子的有力工具。我们现在能够完全从头开始攻击相对较大的系统(目前不能以其他方式做到这一点)，解决当前感兴趣的有争议的问题，并预测过剩电子的新结合机制。未来的项目主要有三个目标。将该方法应用于水团簇阴离子，对于理解水如何溶解电子具有重要意义。这一结果还需要用来校准可用于研究液态水的模型势。文献中对富勒烯阴离子进行了大量的研究。一类新的阴离子态(弱束缚类S态)是否存在以及它们可能具有什么性质一直是有争议的讨论。所开发的方法的应用可以从一开始就完全解决这一争议。此外，可以确定这些状态的性质和主要的结合机制。最后但并非最不重要的是，这种方法应该得到进一步的发展，并研究其他有趣的例子。

In the first stage of this project substantial progress has been made towards the theoretical study of large anions. A new massively parallel platform based on electron propagator theory (called P-RICD-Sigma) and a new complex absorbing potential which makes the calculations of metastable anionic states free of artificial resonances have been developed. We have demonstrated that the implemented second-order electron propagator method performs extremely well in comparasion with higher order coupled-cluster methods. The new class of correlation-bound anions has been introduced and characterized. A novel concerted elementary reaction mechanism has been discovered and named Bond Breaking by a Catalytic Electron (BBCE). The newly developed method and code have become a powerful tool to compute weakly-bound and metastable anions. We are now in the position to attack relatively large systems fully ab initio (which currently cannot be done otherwise), to solve controversial problems of current interest and to predict new binding mechanisms of an excess electron. The future project has mainly three objectives. The application of the method to water cluster anions is of relevance to the understanding of how water solvates electrons. The results are also needed to calibrate model potentials which can be used to study liquid water. Fullerene anions have been much studied in the literature. Whether a new class of anionic states (weakly-bound s-like states) exists and what properties they may have, has been discussed controversially. The application of the method developed can resolve the controversy fully ab initio. Moreover, the properties and prevailing binding mechanisms of these states can be determined. Last but not least, the method should be further developed and other interesting examples studied.