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arXiv · 1501.03141

Large scale GW calculations

Marco Govoni·Giulia Galli
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Abstract

We present GW calculations of molecules, ordered and disordered solids and interfaces, which employ an efficient contour deformation technique for frequency integration, and do not require the explicit evaluation of virtual electronic states, nor the inversion of dielectric matrices. We also present a parallel implementation of the algorithm which takes advantage of separable expressions of both the single particle Green's function and the screened Coulomb interaction. The method can be used starting from density functional theory calculations performed with semi-local or hybrid functionals. We applied the newly developed technique to GW calculations of systems of unprecedented size, including water/semiconductor interfaces with thousands of electrons.

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Marco Govoni, Giulia Galli. 2015-01-13. Large scale GW calculations. https://arxiv.org/abs/1501.03141

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