Low-energy-electron-diffraction fine structure in W(001) for energies from 0 to 35 eV

Low-energy-electron-diffraction (LEED) intensities from the W(001) surface have been measured for incident energies from 0 to 35 eV, azimuthal angle {φ}=0 ^∘{}, and incident angles between 45 ^∘{} and 70 ^∘{}, with particular reference to the fine structure at very low energies. The results have been compared with calculations using a model of the surface barrier described earlier. The experimental curves can be reproduced satisfactorily, provided that (1) the inner potential is allowed to vary with incident energy, (2) the surface damping is strong and energy dependent, and (3) there is a weak dependence of the surface barrier on incident angle.