Regensburg 2010 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
O: Fachverband Oberflächenphysik
O 84: Density functional theory and beyond for real materials IV
O 84.6: Vortrag
Freitag, 26. März 2010, 12:30–12:45, H34
A simple construction of the GW approximation for molecules — •Dietrich Foerster1, Peter Koval2, and Olivier Coulaud3 — 1CPMOH, Bordeaux, France — 2CNRS, INRIA (Hiepacs), Bordeaux, France — 3INRIA (Hiepacs), Bordeaux, France
To model the fundamental processes in organic solar cells where light first generates an exciton that is then separated at the donor acceptor interface is a challenging task and requires an extension of existing computational methods to large aperiodic systems. We chose to extend the LCAO approach to excited states in a simple way by defining a space of dominant functions that spans the space of products with exponential accuracy [1]. Using these functions as a basis, we devised an O(N2) algorithm for computing the Kohn-Sham response function [2] where N is the number of atoms. Our approach simplifies/accelerates the computation of spectra in TDDFT linear response (see the contribution at this symposium of Dr. P. Koval).
In this contribution, we use our construction of the Kohn-Sham response function to give a simple algorithm for the GW approximation. Our results are only “proof of principle” and the complexity of the calculation must still be reduced.
References [1] D. Foerster, J. Chem. Phys. 128, 034108 (2008); P. Koval and D. Foerster, Physica Status Solidi, submitted (2010) arXiv:0910.3796. [2] D. Foerster, P. Koval., J. Chem. Phys. 131 044103 (2009). [3] F. Aryasetiawan and O. Gunnarsson, Rep. Prog. Phys. 61, 237 (1998).