We introduce a method that allows for the calculation of quasiparticle spectra in the GW approximation, yet avoiding any explicit reference to empty one-electron states. This is achieved by expressing the irreducible polarizability operator and the self-energy operator through a set of linear response equations, which are solved using a Lanczos-chain algorithm. We first validate our approach by calculating the vertical ionization energies of the benzene molecule and then show its potential by addressing the spectrum of a large molecule such as free-base tetraphenylporphyrin.
|Titolo:||GW quasiparticle spectra from occupied states only RID F-2982-2011|
|Autori:||Umari P; Stenuit G; Baroni S|
|Data di pubblicazione:||2010|
|Digital Object Identifier (DOI):||10.1103/PhysRevB.81.115104|
|Appare nelle tipologie:||1.1 Journal article|