Beyond the method of images—the interaction of charged particles with real surfaces

A knowledge of the potential energy of a point charge outside a planar surface is important for understanding many charge transfer processes and surface spectroscopies. Whilst the ‘theory of images’ of classical electrostatics can be used to derive this potential, the result is valid only for static charges far from the surface. In this paper we describe recent attempts to consider moving charges near real surfaces, with particular reference to surfaces with dielectric overlayers, and we review experimental studies of the effects of the image force.