An aligned oxidation of carbon monoxide induced by 193 nm irradiation on platinum(113)

The angular and velocity distributions of desorbing CO2 product were studied in the photoinduced CO oxidation on a stepped platinum(113) surface. The CO2 desorption is sharply collimated into directions at ±23° from the bulk surface normal in a plane along the surface troughs. The velocity distribution analysis yields two desorption components with different translational temperatures. One has a high translational energy maximized around ±35° and the other an energy peaked at the surface normal. The surface parallel momentum of hot oxygen atoms is partly retained in the former desorption event.