Development of a wavefunction-based ab-initio method for metals applying the method of increments

本论文的目的是通过增量方案将基于波函数的量子化学相关方法应用于金属。固体的相关能以定域轨道群及其增量的形式展开。第一个应用程序是固体汞，在那里我们取得了很好的协议与实验基态性能。在过去的两年中，我们已经将该方法扩展到镁、锌和镉，这些金属特征比汞更明显。我们已经开发和测试了不同的嵌入方法和用于增量方案的本地化轨道。计算的基态性质与实验值吻合得很好。在优先计划的下一个阶段，我们希望将增量方法扩展到其他IIa族金属和开壳金属，如锂和金。在这两种情况下，可以预期的是，单参考相关的方法使用到现在为止将失败，由于准简并带在费米能级。因此，我们希望为三维实体开发一个多参考增量方案。

The purpose of this proposal is the application of wavefunction-based quantum chemical correlation methods to metals via the incremental scheme. The correlation energy of the solid is expanded in terms of localized orbital groups and increments of these groups. The first application was made for solid mercury, where we achieved a very good agreement with experimental ground-state properties. In the last two years we have extended the method to magnesium, zinc and cadmium, where the metallic character is more pronounced than in mercury. We have developed and tested different approaches for the embedding and the localized orbitals used for the incremental scheme. The calculated ground-state properties agree very well with the experimental values. In the next period of the priority program we want to extend the method of increments to the other group IIa metals and to open-shell metals like lithium and gold. In both cases it is expected that single-reference correlation methods as used up to now will fail due to quasi-degenerate bands at the Fermi level. For that reason we want to develop a multi-reference incremental scheme for three-dimensional solids.