AbstractResults of low energy electron diffraction calculations using the scattering matrix method are presented for the incident energy range 0.5 to 40 eV for the (111) A1 face and a comparison is made with reported measured total current spectroscopy results. It is concluded that the structure of the experimental spectra is determined by elastic diffraction effects and that the TCS technique provides information on the mean inner and absorption potentials in the very low incident energy region.