Dielectric screening : Effects of Core Polarization on Phonons and Quasiparticle Bands

ORAL

Abstract

We investigate the influence of core polarization on the dielectric screening of atoms, molecules and solids with focus on non metallic systems. We compare results for dielectric band structures and for the eigenvalues of the dielectric matrix obtained by varying the number of valence electrons included in our calculations. We show that (semi)-core electronic states may substantially influence the dielectric screening, even if they lie very deep in energy compared to the outermost valence electrons. We then discuss how the changes in dielectric screening observed when including (semi)-core electrons affect computed quasi particle energies at the GW level, and phonon frequencies, e.g. the LO-TO splitting. We focus on closed shell atoms, including Be,Mg, Ca, Ar, Zn, simple diatomic molecules and simple ionic solids, e.g. LiH and NaH.

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Authors

  • Amandeep Kaur

    University of California, Davis

  • Erik Ylvisaker

    University of California, Davis

  • Deyu Lu

    Center for Functional Nanomaterials, Brookhaven National Laboratory, Brookhaven National Laboratory, Brookhaven National Lab, Upton, NY

  • Giulia Galli

    University of California, Davis, Department of Chemistry and Department of Physics, University of California, Davis, Department of Chemistry, University of California, Davis; Department of Physics, University of California, Davis, Dep. of Chemistry, UC Davis, Department of Chemistry, University of California, Davis and Department of Physics, University of California, Davis, UC Davis, Department Of Chemistry, Department Of Physics, University of California, Davis, Department of Chemistry, University of California, Davis 95616

  • Warren Pickett

    University of California, Davis