Methods for calculating potential energy surfaces of image potential states are presented. The methods cover metal-vacuum interfaces, metal-dielectric medium interfaces, and metal-dielectric medium-vacuum interfaces. The metal is approximated as a perfect conductor or as a Fermi-Thomas metal. Potential energy surfaces and the induced charge densities are presented as functions of the properties of the dielectric medium, the metal and the thickness of the absorbed material. (C) 2001 American Institute of Physics.