Dynamic structure factor of gold

We have investigated the role of localized d-bands in the dynamical response of Au, on the basis of ab initio pseudopotential calculations. The density-response function has been evaluated in the random-phase approximation. For small momenta, we have found a double-peak structure in the energy-loss function, which results from the presence of d-electrons. These results are in good agreement with the experimentally determined optical response of gold. We also analyze the dependence of the dynamical structure factor on the wave vector q.