Azimuthal dependence of sticking probability ofO2on Ag(110)

The chemisorption dynamics of ${\mathrm{O}}_2$ on Ag(110) was studied by molecular beams and high-resolution electron energy-loss spectroscopy by measuring the initial sticking probability ${\mathit{S}}_0$ as a function of the molecular translational energy ${\mathit{E}}_{\mathit{i}}$ and angle of incidence ${\mathrm{\theta }}_{\mathit{i}}$ along 〈001〉 and 〈11¯0〉. $S sub 0— scales as ${\mathit{E}}_{\mathit{i}}$ ${\cos }^{\mathit{n}}$ ${\mathrm{\theta }}_{\mathit{i}}$ with n=1.1 along 〈001〉 and n=1.6 along 〈11¯0〉. This indicates that parallel momentum has a role in promoting adsorption. The effect is connected to the amplitude of the corrugation seen by the ${\mathrm{O}}_2$ molecule.