KOVAL, Peter; FOERSTER, Dietrich; COULAUD, Olivier

Métadonnées

Licence d’utilisation du document

KOVAL, Peter
Laboratoire Bordelais de Recherche en Informatique [LaBRI]
High-End Parallel Algorithms for Challenging Numerical Simulations [HiePACS]

FOERSTER, Dietrich
Centre de physique moléculaire optique et hertzienne [CPMOH]

COULAUD, Olivier
Laboratoire Bordelais de Recherche en Informatique [LaBRI]
High-End Parallel Algorithms for Challenging Numerical Simulations [HiePACS]

Langue

Communication dans un congrès

Ce document a été publié dans

Trends in nanotechnology - TNT 2009, 2009-09-07, Barcelona. 2009

Résumé en anglais

The use of the LCAO (Linear Combination of Atomic Orbitals) method for excited states involves products of orbitals that are known to be linearly dependent. We identify a basis in the space of orbital products that is local for orbitals of finite support and with a residual error that vanishes exponentially with its dimension. As an application of our previously reported technique we compute the Kohn--Sham density response function $\chi_{0}$ for a molecule consisting of $N$ atoms in $N^{2}N_{\omega }$ operations, with $N_{\omega}$ the number of frequency points. We test our construction of $\chi_{0}$ by computing molecular spectra directly from the equations of Petersilka--Gossmann--Gross in $N^{2}N_{\omega }$ operations rather than from Casida's equations which takes $N^{3}$ operations. We consider the good agreement with previously calculated molecular spectra as a validation of our construction of $\chi_{0}$. Ongoing work indicates that our method is well suited for the computation of the GW self-energy $\Sigma=\mathrm{i}GW$ and we expect it to be useful in the analysis of exitonic effects in molecules.< Réduire

Mots clés en anglais

Kohn-Sham response function

absorption spectra

Time-dependent density functional theory (TDDFT)

basis of dominant products

Project ANR

Nouveaux Outils pour la Smulation des Solides et Interfaces - ANR-07-CIS7-0005

Origine

Importé de hal

Unités de recherche

Laboratoire Ondes et Matière d'Aquitaine (LOMA) - UMR 5798