Propagating collective excitations in molten salts

Longitudinal as well as transverse dynamics of a molten salt beyond the hydrodynamic region is studied within the generalized collective modes (GCM) approach. An analytical three-variable model is applied to the treat-ment of the coupled long- and short-time charge uctuations. Dispersion laws of propagating kinetic collective excitations such as optic phonon-like modes, heat and shear waves are obtained and analyzed for the case of molten NaCl within the eight-variable GCM scheme, combining the analyt-ical methods and molecular dynamics simulations. Key words: generalized hydrodynamics, collective excitations, ionic liquids, molten salts, longitudinal and transverse dynamics PACS: 05.20.Jj, 61.20.Lc 1