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تسجيل مستخدم جديدThe bandstructure of gold from many-body perturbation theory
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The bandstructure of gold is calculated using many-body perturbation theory (MBPT). Different approximations within the GW approach are considered. Standard single shot G0W0 corrections shift the unoccupied bands up by ~0.2 eV and the first sp-like occupied band down by ~0.4 eV, while leaving unchanged the 5d occupied bands. Beyond G0W0, quasiparticle self-consistency on the wavefunctions lowers the occupied 5d bands by 0.35 eV. Globally, many-body effects achieve an opening of the interband gap (5d-6sp gap) of 0.35 to 0.75 eV approaching the experimental results. Finally, the quasiparticle bandstructure is compared to the one obtained by the widely used HSE (Heyd, Scuseria, and Ernzerhof) hybrid functional.
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