PROJECTS

Wannier-type orbital based Hartree-Fock (-Wigner) electronic structure theory and wavefunction-based correlation treatment for periodic systems

PRINCIPAL INVESTIGATOR

Prof. Dr. Michael Dolg Universität zu Köln Theoretische Chemie Greinstraße 4 50939 Köln 0221/470-6893 0221/470-6896 m.dolg@uni-koeln.de

PROJECT RESEARCH ASSISTANT

ABSTRACT

A Wannier-type orbital based Hartree-Fock electronic structure program for periodic systems will be extended and coupled to electron correlation modules (for the total energy per unit cell as well as for correlation corrections to bandstructures) working in a local orbital basis. Density fitting schemes will be applied to reduce the computational effort at the Hartree-Fock level. An automatized version of the so-called incremental scheme for the evaluation of the correlation energy per unit cell will be implemented at the second-order Møller-Plesset perturbation theory (MP2) and singles and doubles Coupled-Cluster (CCSD) level. The perturbative inclusion triples at the CC level will be attempted (CCSD(T)). Furtheron the possiblity of a one-step second-order Møller-Plesset perturbational evaluation of the correlation energy per unit cell will be explored. Finally, Hartree-Fock-Wigner theory, i.e., modified Hartree-Fock equations accounting for electron correlation in terms of a functional of so-called Wigner intracules, will be implemented as an alternative to the MP2 and CCSD/CCSD(T) approaches.