PROJECTS

PRINCIPAL INVESTIGATOR

PROJECT RESEARCH ASSISTANT

ABSTRACT

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. We want to extend the method to other metals, where the metallic character is more pronounced as compared to mercury. We will develop different approaches concerning the embedding and the localized orbitals used for the incremental scheme. The materials in mind are magnesium and beryllium. For the latter one the 2s and 2p band are quasi-degenerate, which can cause problems with single-reference correlation methods like coupled cluster. For that reason we want to develop a multi-reference incremental scheme for three-dimensional solids. Also a combination of the incremental scheme with density functional methods is possible, when we use local Kohn-Sham orbitals instead of Hartree-Fock orbitals.