We address the treatment of transition metal atoms in GW electronic-structure calculations within the plane-wave pseudo-potential formalism. The contributions of s and p semi-core electrons to the self-energy, which are essential to grant an acceptable accuracy, are dealt with using a recently proposed scheme whereby the exchange components are treated exactly at the G(0)W(0) level, whereas a suitable approximation to the correlation components is devised. This scheme is benchmarked for small gold nano-clusters, resulting in ionization potentials, electron affinities, and density of states in very good agreement with those obtained from calculations where s and p semicore states are treated as valence orbitals, and allowing us to apply this same scheme to clusters of intermediate size, Au-20 and Au-32, that would be otherwise very difficult to deal with.
|Titolo:||Approximate treatment of semicore states in GW calculations with application to Au clusters|
|Autori:||Xian, J. W.; Baroni, S.; Umari, P.|
|Rivista:||THE JOURNAL OF CHEMICAL PHYSICS|
|Data di pubblicazione:||2014|
|Digital Object Identifier (DOI):||10.1063/1.4868439|
|Appare nelle tipologie:||1.1 Journal article|