A Kohn-Sham-Like Model for the 1-Body Reduced Density Matrix
Paul Johnson
Department of Chemistry,
McMaster University,
Hamilton, Ontario, Canada
Lundi, 24 octobre 2011,
11h00 Bibliothèque 4e étage,
tour 12 - 13, site Jussieu
Kohn-Sham density functional theory (KS-DFT) is a very popular and successful approach to approximating the many-body Schrödinger equation due to its favourable speed and moderate accuracy. A non-interacting reference state (Slater determinant) which reproduces the correct electron density is employed. A correction term is then added to connect the fictitious non-interacting system to the real physical system of interest. Unfortunately, this correction term is unknown, and likely unknowable.
The goal of this work is to produce a method in the spirit of the KS approach using the 1-body reduced density matrix (1-RDM) as the fundamental variable rather than the electron density. A strongly-correlated reference state (pairing wavefunction) is employed to achieve this result. Two different approaches to achieve this goal will be presented which are able to treat open- and closed-shell systems. These approaches are able to reproduce both the non-interacting and strongly-correlated limits.