English
 
Help Privacy Policy Disclaimer
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT

Released

Journal Article

Impact of widely used approximations to the G0W0 method: an all-electron perspective

MPS-Authors
/persons/resource/persons21817

Li,  Xinzheng
Theory, Fritz Haber Institute, Max Planck Society;

/persons/resource/persons21564

Gomez Abal,  Ricardo
Theory, Fritz Haber Institute, Max Planck Society;

/persons/resource/persons21677

Jiang,  Hong
Theory, Fritz Haber Institute, Max Planck Society;

/persons/resource/persons22064

Scheffler,  Matthias
Theory, Fritz Haber Institute, Max Planck Society;

External Resource
No external resources are shared
Fulltext (public)

1367-2630_14_2_023006.pdf
(Publisher version), 971KB

Supplementary Material (public)
There is no public supplementary material available
Citation

Li, X., Gomez Abal, R., Jiang, H., Ambrosch-Draxl, C., & Scheffler, M. (2012). Impact of widely used approximations to the G0W0 method: an all-electron perspective. New Journal of Physics, 14(2): 023006. doi:10.1088/1367-2630/14/2/023006.


Cite as: http://hdl.handle.net/11858/00-001M-0000-0010-1694-A
Abstract
Focusing on the fundamental band gaps in Si, diamond, BN, LiF, AlP, NaCl, CaSe and GaAs, and the semicore d-state binding energies in ZnS, ZnSe, ZnTe, CdS, CdSe, CdTe and GaN, we study the differences between the all-electron (AE) G0W0G0W0 method. Leaving aside issues related to the choice of PPs within PP-G0W0, we analyze in detail the well-known discrepancies between AE-G0W0 and PP-G0W0 band gaps by separately addressing the approximations underlying PP-G0W0, i.e. the frozen-core approximation, the core–valence partitioning and the use of pseudo-wavefunctions. The largest differences, of the order of eV, appear in the exchange part of the self-energy and the exchange–correlation potential due to the core–valence partitioning. These differences cancel each other and, in doing so, make the final core–valence partitioning effect on the band gaps controllable when the semicore states are treated as valence states. This cancelation, however, is incomplete for semicore d-state binding energies, due to the strong interaction between these semicore states and the deep core. From our comprehensive analysis, we conclude that reliably describing the many-body interactions at the G0W0 level and providing benchmark results require an AE treatment.