Optimized surface-slab excited-state muffin-tin potential and surface core level shifts

An optimized muffin-tin (MT) potential for surface slabs with preassigned surface core-level shifts (SCLS's) is presented. By using the MT radii as adjustable parameters the model is able to conserve the definition of the SCLS with respect to the bulk and concurrently to generate a potential that is continuous at the MT radii. The model is conceived for elastic electron scattering in a surface slab with exchange-correlation interaction described by the local density approximation. The model employs two data bases for the self-energy of the signal electron (after Hedin and Lundqvist or Sernelius). The potential model is discussed in detail with two surface structures Be(1010), for which SCLS's are available, and Cu(111)p(2×2)Cs, in which the close-packed radii of the atoms are extremely different. It is considered plausible that tensor LEED based on an optimized MT potential can be used for determining SCLS's.