Surface Science 94 (1980) 179-203 0 Nort}I-Holland abashing Company ELECTROSTATIC ENERGY AND SCREENED CHARGE INTERACTION NEAR THE SURFACE OF METALS WITH DIFFERENT FERMI SURFACE SHAPE A.M. GABOVICH, L.C. IL’CHENKO, E.A. PASI-IITSKII and Yu .A. ROMANOV Institute of Physics, Academy of Sciences of the Ukrainian SSR, Prospeki Nauki 144, KiaJ 28, USSR Received 18 April 1979 Using the Poisson equation Green function for a self-consistent field in a spatially inhomo- geneous system, expressions for the electrostatic energy and screened charge interaction near the surface of a semi-infinite metal and a thin quantizing film are derived. It is shown that the decrease law and Friedel oscillation amplitude of adsorbed atom indirect interaction are deter- mined by the electron spectrum character and the Fermi surface shape. The results obtained enable us to explain, in particular, the submonolayer adsorbed film structure on the W and MO surfaces. 1. Introduction For a theory of a number of processes on the interface of media with different dielectric permittivities (e.g., physical adsorption and chemisorption, photo-, auto- and thermoelectron and ion emission, catalysis and electrolysis, the contact phe- nomena and processes in biological membranes), a knowledge of a detailed spatial electrostatic potential charge (ion, electron) distribution near the surface of a solid is required. The electrostatic interaction of charges placed in a vacuum or insulator with a metal surface was investigated theoretically in a large number of papers (see, e.g., refs. [l-8]). However, in all these papers the treatment was restricted to the model of an isotropic metal with a spherical electron Fermi surface (FS) or,to the Thomas-Fermi approximation (TFA) for the static dielecttic permittivity of a metal. Along with the above mentioned charge interaction with the metal surface, also of large interest is the study of indirect interaction between the charged adsorbed atoms on the metal surface via itinerant substrate electrons, taking into account the screening effects [9]. It is known that in the bulk of a metal the step character of a Fermi electron distribution leads to the so-called Friedel oscillations (FO) of the screened Coulomb potential which, for the spherical FS, decreases at large distances 179