Diffuse low-energy electron diffraction study of disordered O/Ni(100)

Abstract

From an analysis of diffuse low-energy electron diffraction data, we have determined the likely local adsorption site of disordered oxygen on the Ni(100) surface under conditions of low temperature and low coverage. We found the structure which yielded the best fit with experiment to be that in which the oxygen atoms are displaced off the fourfold hollow sites towards the bridge sites by 0.4 Å. This gave rise to low values, of 0.15 and 0.17, respectively, of the Pendry R (reliability) factor for two different sets of Y-function screens (E=48/52 and 60/64 eV). The misleading nature of the conclusions resulting from the use of only one Y-function screen is pointed out.