Electron spectroscopic characterization of oxygen adsorption on gold surfaces: I. Substrate impurity effects on molecular oxygen adsorption in ultra high vacuum

Tentative adsorption on clean gold (110) and (111) crystals of molecular oxygen in the pressure range 10 ^?10 to 10 ^?5 Torr, at a temperature varying between 100 and 800 K is reported together with the subsequent characterization of the surfaces by High Resolution Electron Energy Loss, Auger and X-ray Photoelectron Spectroscopies. It is found that oxygen does not adsorb in these UHV conditions, except when a contaminant is present on the surface. Such an interaction with a low level silicon impurity is described.