W. Nelson,1, ∗ P. Bokes,2, 3 Patrick Rinke,3, 4 and R. W. Godby1, 3, †
1Department of Physics, University of York, Heslington, York YO10 5DD, United Kingdom
2Department of Physics, Faculty of Electrical Engineering and Information Technology, Slovak University of Technology, Ilkoviˇcova 3, 841 04 Bratislava, Slovak Republic
3European Theoretical Spectroscopy Facility (ETSF)
4Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4–6, 14195 Berlin, Germany
(Dated: September 11, 2018)
Abstract
Atomic hydrogen provides a unique test case for computational electronic structure methods, since its electronic excitation energies are known analytically. With only one electron, hydrogen contains no electronic correlation and is therefore particularly susceptible to spurious self-interaction errors introduced by certain computational methods. In this paper we focus on many-body perturbationtheory (MBPT) in Hedin’s GW approximation. While the Hartree-Fock and the exact MBPT self-energy are free of self-interaction, the correlation part of the GW self-energy does not have this property. Here we use atomic hydrogen as a benchmark system for GW and show that the selfinteraction part of the GW self-energy, while non-zero, is small. The effect of calculating the GW self-energy from exact wavefunctions and eigenvalues, as distinct from those from the local-density approximation, is also illuminating.
To download the article click on the link below:
https://arxiv.org/pdf/cond-mat/0701592.pdf
1Department of Physics, University of York, Heslington, York YO10 5DD, United Kingdom
2Department of Physics, Faculty of Electrical Engineering and Information Technology, Slovak University of Technology, Ilkoviˇcova 3, 841 04 Bratislava, Slovak Republic
3European Theoretical Spectroscopy Facility (ETSF)
4Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4–6, 14195 Berlin, Germany
(Dated: September 11, 2018)
Abstract
Atomic hydrogen provides a unique test case for computational electronic structure methods, since its electronic excitation energies are known analytically. With only one electron, hydrogen contains no electronic correlation and is therefore particularly susceptible to spurious self-interaction errors introduced by certain computational methods. In this paper we focus on many-body perturbationtheory (MBPT) in Hedin’s GW approximation. While the Hartree-Fock and the exact MBPT self-energy are free of self-interaction, the correlation part of the GW self-energy does not have this property. Here we use atomic hydrogen as a benchmark system for GW and show that the selfinteraction part of the GW self-energy, while non-zero, is small. The effect of calculating the GW self-energy from exact wavefunctions and eigenvalues, as distinct from those from the local-density approximation, is also illuminating.
To download the article click on the link below:
https://arxiv.org/pdf/cond-mat/0701592.pdf
Hello, my name is Dr Abderrahmane Reggad. I'm a 51 year old and I am a researcher in materials' sciences. 
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