Conserving quasiparticle calculations for small metal clusters
Department and Research Center OPTIMAS, Kaiserslautern University, P.O. Box 3049, 67653 Kaiserslautern, Germany
Corresponding author: a firstname.lastname@example.org
Revised: 15 June 2009
Published online: 21 July 2009
A novel approach for GW-based calculations of quasiparticle properties for finite systems is presented, in which the screened interaction is obtained directly from a linear response calculation of the density-density correlation function. The conserving nature of our results is shown by explicit evaluation of the f-sum rule. As an application, energy renormalizations and level broadenings are calculated for the closed-shell Na9+ and Na21+ clusters, as well as for Na4. Pronounced improvements of conserving approximations to RPA-level results are obtained.
PACS: 73.22.-f – Electronic structure of nanoscale materials: clusters, nanoparticles, nanotubes, and nanocrystals / 73.20.Mf – Collective excitations (including excitons, polarons, plasmons and other charge-density excitations) / 36.40.Gk – Plasma and collective effects in clusters / 71.45.Gm – Exchange, correlation, dielectric and magnetic response functions, plasmons
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2009