Eur. Phys. J. B (2012) 85: 285
https://doi.org/10.1140/epjb/e2012-30291-y

Regular Article

GW calculations of the band gaps of BC₂N polytypes

Department of Materials Science, Fudan University, Shanghai 200433, P.R. China

^a e-mail: gaosp@fudan.edu.cn

Received: 5 April 2012
Received in final form: 30 May 2012
Published online: 20 August 2012

Abstract

Band structures for BC₂N polytypes are calculated using density functional theory with local density approximation. Band energies at high symmetry k-points are corrected using the GW method to accurately predict the band gap. β-BC₂N and w-BC₂N have indirect band gaps. z-BC₂N has a direct band gap. The differences between direct band gap energies and indirect band gap energies are very small for both z*-BC₂N and t-BC₂N, indicating a quasi-direct band gap character.