Studies on Chemisorption of Nitrogen on Tungsten with the Field Emission Microscope

The microsocopic studies of N 2 on W have been made and compared with the results of the macroscopic studies. The sites of the non-dissociative chemisorption ε exist on and around the (111) plane and around the (011) plane, and the ε -adatoms increase the work function of these planes as much as 0.5 eV. While, the sites of the dissociative chemisorption ζare on and around the (001) and (111) planes, and the work function is lowered as much as 0.2 eV by the ζ-adsorption. The situation of the α-site is not determined because of its small amount. The previous studies of the work function change are interpreted reasonably by the α ε ζ-model without the suspision of impurities. These interpretations entirely differ from those of Ehrlich et al. by the αβ-model.