Utility of Patterson synthesis for surface structural studies with atomic beam diffraction.

Abstract

Because of the close relationship between the structure factor of kinematic diffraction theory in standard three-dimensional crystallography and the eikonal approximation used in atomic beam diffraction for surface structural studies, it is straightforward to transfer the concept of Patterson synthesis to the latter case and to deduce its applicability range. The power of the Patterson method for He diffraction is demonstrated by applying it to the chemisorption system Ni(111)+(2\ifmmode\times\else\texttimes\fi{}2)H. The Patterson function derived from experimental intensity data shows directly that the primitive unit cell contains two H atoms, allows determination of the adatom distance, and thus leads immediately to the honeycomb adatom arrangement suggested previously by low-energy electron diffraction.