Surface structural analysis of LiF(1 0 0) thin films grown on Pt(1 1 1)

The surface structure of a multilayer LiF(1 0 0) thin film grown on Pt(1 1 1) from the vapor has been determined by the automated tensor low energy electron diffraction method. The final structure, which refined to a Pendry R-factor (RP) of 0.24, had a surface corrugation (Δ1) of 0.24±0.04 Å due to the Li+ being displaced towards the bulk, leaving the initially coplanar F− unshifted. A similar intralayer corrugation due to the movement of the Li+ was also observed in the layer immediately under the surface layer, although to a lesser degree: Δ2=0.07±0.04 Å. This asymmetric relaxation resulted in the reduction of the first interlayer spacing, d(F2–Li1), to 1.77±0.06 Å from the ideal value of 2.01 Å. The second interlayer spacing, d(Li3–F2), was within error bars of the bulk value, 2.01 Å.