INELASTIC-COLLISION MODEL OF LOW-ENERGY ELECTRON DIFFRACTION FROM SOLID SURFACES

An inelastic-collision model of low-energy electron diffraction (LEED) is proposed in which the electron-electron interactions in the solid limit the penetration of the incident elastic beam to a depth of 10 Å or less for electrons between 15 and 150 eV incident energy. The inelastic-collision-induced damping of the elastic wave field inside the crystal plus the occurrence of multiple internal beams provide the ingredients for an elementary intuitive description of the occurrence of fractional-order peaks in LEED intensities. The damping also reduces substantially the magnitude of multiple scattering peaks in the LEED intensity. Both of these results are derived using a propagator formalism in which single electron propagators characteristic of an interacting electron fluid are utilized in the description of the electron-lattice interaction. © 1969.