Abstract The longitudinal field component induced by the dielectric screening of the incident radiation at the surface has recently been shown to yield a considerable influence on the photoemission spectra. The hydrodynamic model for the electrodynamic surface response shows surprisingly good agreement with normal emission experimental spectra for layered dichalcogenides. However, it is not applicable for photon frequencies below the plasmon energy ωp and was therefore extended to a two-step density model to simulate the multipol mode below ωp. As a consequence a similar behaviour in the calculated photoemission spectra could be followed passing to low frequencies. However, the modelling of the surface is not free of parameters, sensitively depending on the rather arbitrary position of the outermost electron density steps. To relate these quantities to the real density of a layered crystal, a self-consistent calculation of the electrodynamic surface response, for a system with crystalline periodicity in the surface normal direction and full translational symmetry in the parallel direction, is in development. In contrast to some standard applications to the jellium model, Green's functions are used which prove to be very appropriate for this actual task.