Heyd-Scuseria-Ernzerhof hybrid functional for calculating the lattice dynamics of semiconductors

Autor(en)

Kerstin Hummer, Judith Harl, Georg Kresse

Abstrakt

We present an ab initio study of the lattice dynamics of group-IV elemental semiconductors and insulators using a finite differences approach. The investigated solids include cubic diamond (C), silicon (Si), germanium (Ge), and the zero-gap semiconductor gray tin (α-Sn). The main objective of this work is to examine the performance of the screened hybrid functional (HSE) proposed by Heyd, Scuseria, and Ernzerhof [J. Chem. Phys. 118, 8207 (2003); J. Chem. Phys. 124, 219906(E) (2006)] for calculating phonon-dispersion relations. We find that all local and semilocal functionals tend to underestimate the phonon frequencies, with the errors increasing with increasing atomic mass. For α-Sn, semilocal functionals even qualitatively fail to describe the dispersion of the highest optical phonon mode. We show that this is related to semilocal functionals predicting α-Sn to be a metal, whereas experimentally it is a zero-gap semiconductor. The HSE functional yields the correct electronic band structure resulting in qualitatively correct phonon-dispersion relations for all four solids. Quantitatively, the phonon frequencies are slightly overestimated using HSE, in particular for the lighter elements C and Si. Our results are compared to previously reported theoretical findings.

Organisation(en)

Computergestützte Materialphysik

Journal

Physical Review B

Band

80

Anzahl der Seiten

12

ISSN

1098-0121

DOI

https://doi.org/10.1103/PhysRevB.80.115205

Publikationsdatum

2009

Peer-reviewed

Ja

ÖFOS 2012

103009 Festkörperphysik, 103015 Kondensierte Materie, 103025 Quantenmechanik, 103036 Theoretische Physik

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/c4f0b3d5-9795-4f58-91a0-d291f6ed9ae5