Quasiparticle band structures and lifetimes in noble metals using Gaussian orbital basis sets

Abstract

We present the calculations of quasiparticle bandstructures and lifetimes for noble metals Cu and Ag within the GW approximation based on localized Gaussian orbital basis sets. For Cu, both the calculated positions of the d bands and the width of the d bands are within 0.1 eV compared to the experimental results. For Ag, partial core correction should be included in the pseudopotential to get reliable positions of the d bands. The calculated lifetimes agree with the experiment in the energy region away from the Fermi level, but deviate from the experimental results near the Fermi level where short-range interactions which GW approach fails to describe play an important role. For a better description of the lifetime near the Fermi level, terms beyond the GW approximation in the many-body perturbation theory need to be considered.