STRUCTURES OF SURFACES STUDIED BY X-RAY DIFFRACTION. Robert Feidenhansl, Department of Solid State Physics, DK-4000 Roskilde, Denmark

In surface science the use of x-ray scattering has developed to the point where it now can be applied to solve a great diversity of problems, including complex reconstructions, surfaces in electrochemical cells, solid/liquid interfaces and much more. These developments have relied both on improvements in sources of synchrotron radiation, and on our understanding of how to exploit them for the study of surfaces.

After an historical overview, the basic principles of the technique will be discussed. Examples of complex reconstructions of surfaces induced by adsorbates (sulphur on metal surfaces and surface alloying) will be shown, where the structures were solved using methods adapted from conventional crystallography. The talk will conclude by comparing x-ray scattering with other surface structural tools and discuss future directions using examples of surface science performed under non-ultra-high vacuum conditions.