Phonon Dispersion in Noble Metals

Abstract

Abstract A new lattice dynamical model comprising various interactions among the constituents of noble metals is developed. The model assumes central core-core coupling extending to the first neighbours only. Overlap interactions among neighbouring d-shells are expressed in terms of an angular parameter. Volume interactions for core-conduction electrons and d-shell-conduction electrons are described through a simple expression. Interactions between core and d-shell are also accounted for adequately. The lattice is considered in equilibrium under the volume dependent energy of cores, conduction electrons and the d-shell electrons. The obtained dispersion relations for copper and silver are compared with (a) experimental data, (b) results of a recent first-principle calculation and (c) results of a recent phenomenological study.