LEED intensity measurements and surface structures: The dynamical approach (Illustrated by Ni/chemisorbed Na system)

The authors are concerned with extraction of structural information from LEED intensity measurements by comparison with dynamical calculations for trial structures. The technique is illustrated by the system of sodium on a nickel (100) surface. Experiments are described; resolution is investigated and found to be about +or-0.1 AA. The top layer of a clean nickel (100) surface is shown to be dilated by not more than 0.15 AA and the determination of the sodium nickel distance of 2.9 AA reported earlier by Andersson and Pendry is described in greater detail.