Adsorption dynamics of O2 on Cu(100) and on reconstructed Cu(100)-(2√2 x √2)R45°-O at 300 and 553K were investigated by using a supersonic molecular-beam surface-scattering technique. Experimental results suggested that an activated direct adsorption channel operated on clean Cu(100), whereas O2 adsorption on the reconstructed Cu(100) was mediated by a precursor state or by steering effects. First-principles molecular-dynamics simulations and potential-energy surface calculations showed that the nature of the adsorption dynamics of O2 was different for the clean and reconstructed Cu(100) surfaces. The O2 molecule was likely to diffuse away from the reconstructed area or to desorb completely from the surface while, in the case of the clean Cu(100) surface, adsorption occurred via a direct dissociative trajectory. It was also found that, in the case of the reconstructed surface, the steering occurred higher over the surface and that the recoil effect did not modify the surface as much as in the case of the clean surface. Moreover, the mobility of O and Cu adatoms on the reconstructed Cu surface was significantly lower than that on the clean surface; both in the direction of the missing rows and in the direction perpendicular to them.

Adsorption and Diffusion Dynamics of Atomic and Molecular Oxygen on Reconstructed Cu(100). S.Jaatinen, J.Blomqvist, P.Salo, A.Puisto, M.Alatalo, M.Hirsimäki, M.Ahonen, M.Valden: Physical Review B, 2007, 75[7], 075402 (8pp)