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arXiv · 0902.4605

Conserving quasiparticle calculations for small metal clusters

George Pal·Yaroslav Pavlyukh·Hans Christian Schneider·Wolfgang Huebner
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Abstract

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 Na$_9^+$ and Na$_{21}^+$ clusters, as well as for Na$_4$. Pronounced improvements of conserving approximations to RPA-level results are obtained.

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George Pal, Yaroslav Pavlyukh, Hans Christian Schneider, Wolfgang Huebner. 2009-02-26. Conserving quasiparticle calculations for small metal clusters. https://doi.org/10.1140/epjb/e2009-00253-9

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