<font>Cu</font>(111) SURFACE RELAXATION BY VLEED

Abstract

Very-low-energy electron diffraction (VLEED) intensities from a clean Cu (111) surface have been measured in detail in the energy range 15–100 eV by low-energy electron microscope (LEEM). This enabled the elimination of possible disturbances due to stray magnetic fields. Corresponding theoretical I–V curves have been obtained in good agreement with experimental data when an image-type surface barrier and anisotropy of the electron attenuation were taken into account. The reliability factor analysis indicates a slight expansion of the topmost interatomic spacing of Cu (111) relative to its bulk value.