Influence of External Stress on Surface Reaction Dynamics

In exploring the dynamics of dissociative chemisorption of $\mathrm{O}{}_2$ on clean and O-covered Cu(001), we demonstrate that the chemisorption is very sensitive to uniaxial tensile stress within an elastic limit. The stress enhances the dissociative chemisorption on clean Cu(001) when the translational energy of incident $\mathrm{O}{}_2$ is below 250 meV, and suppresses it when the energy is above 250 meV. In the case of an oxygen-covered Cu(001)- $(2\sqrt{2}\times \sqrt{2})$ surface, the dissociative adsorption probability of $\mathrm{O}{}_2$ decreases as the stress increases. The effect of external stress on the $\mathrm{O}{}_2$ dissociation dynamics is different between clean and O-covered surfaces.