Active phase for inclined CO2 desorption on Rh(1 1 0) in steady-state CO oxidation

The angular and velocity distributions of desorbing CO2 and LEED spot intensities were examined in steady-state CO oxidation on Rh(1 1 0) and Pd(1 1 0). On Rh(1 1 0), in the limited CO pressure range, the angular distribution splits into bi-directional lobes collimating at ±24° off normal along the [0 0 1] direction and the meta-stable (1×2) structure stabilized by oxygen is maximized. On the other hand, neither inclined CO2 desorption nor meta-stable (1×2) was found on Pd(1 1 0).