Monday, November 5, 2012

1211.0416 (Noa Marom et al.)

A Benchmark of GW Methods for Azabenzenes: Is the GW Approximation Good
Enough?
   [PDF]

Noa Marom, Fabio Caruso, Xinguo Ren, Oliver Hofmann, Thomas Körzdörfer, James R. Chelikowsky, Angel Rubio, Matthias Scheffler, Patrick Rinke
Many-body perturbation theory in the GW approximation is a useful method for describing electronic properties associated with charged excitations. A hierarchy of GW methods exists, starting from non-self-consistent G0W0, through partial self-consistency in the eigenvalues (ev-scGW) and in the Green function (scGW0), to fully self-consistent GW (scGW). Here, we assess the performance of these methods for benzene, pyridine, and the diazines. The quasiparticle spectra are compared to photoemission spectroscopy (PES) experiments with respect to all measured particle removal energies and the ordering of the frontier orbitals. We find that the accuracy of the calculated spectra does not match the expectations based on their level of self-consistency. In particular, for certain starting points G0W0 and scGW0 provide spectra in better agreement with the PES than scGW.
View original: http://arxiv.org/abs/1211.0416

No comments:

Post a Comment