Quasiparticle energies for large molecules: a tight-binding GW approach
Materials Science
2009-11-10 v1
Abstract
We present a tight-binding based GW approach for the calculation of quasiparticle energy levels in confined systems such as molecules. Key quantities in the GW formalism like the microscopic dielectric function or the screened Coulomb interaction are expressed in a minimal basis of spherically averaged atomic orbitals. All necessary integrals are either precalculated or approximated without resorting to empirical data. The method is validated against first principles results for benzene and anthracene, where good agreement is found for levels close to the frontier orbitals. Further, the size dependence of the quasiparticle gap is studied for conformers of the polyacenes () up to n = 30.
Cite
@article{arxiv.cond-mat/0411024,
title = {Quasiparticle energies for large molecules: a tight-binding GW approach},
author = {T. A. Niehaus and M. Rohlfing and F. Della Sala and A. Di Carlo and Th. Frauenheim},
journal= {arXiv preprint arXiv:cond-mat/0411024},
year = {2009}
}
Comments
10 pages, 5 eps figures submitted to Phys. Rev. A