Extension of LCAO to excited states
KOVAL, Peter
High-End Parallel Algorithms for Challenging Numerical Simulations [HiePACS]
Laboratoire Bordelais de Recherche en Informatique [LaBRI]
High-End Parallel Algorithms for Challenging Numerical Simulations [HiePACS]
Laboratoire Bordelais de Recherche en Informatique [LaBRI]
KOVAL, Peter
High-End Parallel Algorithms for Challenging Numerical Simulations [HiePACS]
Laboratoire Bordelais de Recherche en Informatique [LaBRI]
< Reduce
High-End Parallel Algorithms for Challenging Numerical Simulations [HiePACS]
Laboratoire Bordelais de Recherche en Informatique [LaBRI]
Language
en
Autre communication scientifique (congrès sans actes - poster - séminaire...)
This item was published in
Trends in nanotechnology - TNT 2009, 2009-09-07, Barcelona. p. 2 pages
English Abstract
We extend the LCAO (Linear Combination of Atomic Orbitals) method to excited states by constructing a particularly simple basis in the space of orbital products. The residual error of our procedure vanishes exponentially ...Read more >
We extend the LCAO (Linear Combination of Atomic Orbitals) method to excited states by constructing a particularly simple basis in the space of orbital products. The residual error of our procedure vanishes exponentially with the number of products and our procedure avoids auxiliary sets of fitting functions and their intrinsic ambiguities. As an application of our technique, we compute the Kohn--Sham density response function $\chi_{0}$ for a molecule consisting of $N$ atoms in $O(N^{2}N_{\omega })$ operations, with $N_{\omega }$ the number of frequency points. Our construction of $\chi_{0}$ allows us to compute molecular spectra directly from the equations of Petersilka--Gossmann--Gross in $O(N^{2}N_{\omega })$ operations rather than from Casida's equations which takes $O(N^{3})$ operations. Ongoing work indicates that our method is well suited to a computation of the GW self-energy $\Sigma=\mathrm{i}GW$ and we expect a similar situation for the Bethe--Salpeter equation.Read less <
English Keywords
Kohn-Sham response function
TDDFT linear response
Basis of dominant functions
ANR Project
Nouveaux Outils pour la Smulation des Solides et Interfaces - ANR-07-CIS7-0005
Origin
Hal imported