Diffusion of O Atoms at Ru(0001) Surface Induced by Collision of O₂ with High Kinetic Energy

Abstract

Oxygen translational energy effects on initial oxidation processes and saturation coverage of O at a Ru(0001) surface were investigated using supersonic O₂ molecular beams and synchrotron radiation photoemission spectroscopic techniques. The change of surface core level spectrum of Ru 3d_5/2 by irradiation of O₂ beams with high translational energy indicates occurrence of collision-induced oxygen migration at the oxidized Ru(0001) surface. We suggest that such collision-induced migration provides suitable sites for dissociative adsorption of O₂, resulting in higher O coverage at the Ru(0001) surface.