Investigation of Cu and Ni Band Structure above the Vacuum Level Using Low Energy Electron Reflection

Incidence angle dependent elastic electron reflection curves in the 0 to 30 eV range are measured on Cu(111) and Ni(111) using target current regime. They are compared with the calculated ones. Computations are made very fast using a simple approximation. The extrema of the reflection energy derivative are shown to correspond unambigiously to definite critical points of bands. These points are mapped when the energies of the experimental extrema are compared with the calculated ones. Varying the incidence angle, in this way bands in the variety of Brillouin zone directions may be investigated.