Theory of local dynamical magnetic susceptibilities from the Korringa-Kohn-Rostoker Green function method

Within the framework of time-dependent density functional theory combinedwith the Korringa-Kohn-Rostoker Green function formalism, we present a real-space methodology to investigate dynamical magnetic excitations from first principles. We set forth a scheme which enables one to deduce the correct effective Coulomb potential needed to preserve the spin-invariance signature in the dynamical susceptibilities, that is, the Goldstone mode. We use our approach to explore the spin dynamics of 3d adatoms and different dimers deposited on a Cu(001) with emphasis on their decay to particle-hole pairs.