THE ANGULAR-DEPENDENCE OF DIFFUSE LEED INTENSITIES AND ITS STRUCTURAL INFORMATION-CONTENT

The structural determination of disordered adsorbates from diffuse LEED intensities has so far relied on measured angle-dependent intensity maps taken at fixed energies. It is therefore important to understand the structural information content of such intensity maps. We have examined the degree of angular dependence of the diffuse intensities, since this is the foremost factor affecting the density of information content. To that end, we have measured and calculated energy-dependent diffuse I-V curves at nearby exit angles: diffuse I-V curves are very promising alternatives to the fixed-energy diffuse LEED maps. In particular, we address the issue of how densely diffuse LEED maps and diffuse I-V curves should optimally be sampled.