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arXiv · 0910.0791

GW quasi-particle spectra from occupied states only

P. Umari·G. Stenuit·S. Baroni
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Abstract

We introduce a method that allows for the calculation of quasi-particle 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.

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P. Umari, G. Stenuit, S. Baroni. 2009-10-05. GW quasi-particle spectra from occupied states only. https://doi.org/10.1103/physrevb.81.115104

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