Stability of low-energy electron diffraction fractional-order beam intensities and intralayer multiple scattering

Low-energy electron diffraction (LEED) intensity measurements on adsorbed oxygen on Cu{001} at varying coverage and LEED calculations of spectra of adsorbed Al on Si{111} at several coverages show the fractional-order spectra to be remarkably independent of surface coverage. Such stability of the fractional-order spectra implies both negligible scattering between adsorbed atoms and the same substrate environment around each adsorbed atom. When such stability is found in LEED intensity measurements during adsorption experiments, the adsorbate environment can sometimes be determined by LEED intensity analysis for complicated structures and even for structures with no long-range order. © 1983 The American Physical Society.