1202.0230 (Hannes Hübener et al.)

Performance of local orbital basis sets in the self-consistent
Sternheimer method for dielectric matrices of extended systems    [PDF]

Hannes Hübener, Miguel A. Pérez-Osorio, Pablo Ordejón, Feliciano Giustino

We present a systematic study of the performance of numerical pseudo-atomic
orbital basis sets in the calculation of dielectric matrices of extended
systems using the self-consistent Sternheimer approach of [F. Giustino et al.,
Phys. Rev. B 81 (11), 115105 (2010)]. In order to cover a range of systems,
from more insulating to more metallic character, we discuss results for the
three semiconductors diamond, silicon, and germanium. Dielectric matrices
calculated using our method fall within 1-3% of reference planewaves
calculations, demonstrating that this method is promising. We find that
polarization orbitals are critical for achieving good agreement with planewaves
calculations, and that only a few additional \zeta 's are required for
obtaining converged results, provided the split norm is properly optimized. Our
present work establishes the validity of local orbital basis sets and the
self-consistent Sternheimer approach for the calculation of dielectric matrices
in extended systems, and prepares the ground for future studies of electronic
excitations using these methods.

View original: http://arxiv.org/abs/1202.0230