Non-equilibrium vibrational kinetics and ‘hot atom'' models in the recombination of hydrogen atoms on surfaces

Non-equilibrium vibrational kinetics as recently developed for adlayers is applied to experimental data on H-atom recombination and abstraction at solid surfaces. This model allows one to fit vibrational and translational energy distribution functions of the excited diatoms leaving the surface. Eley–Rideal and Langmuir–Hinshelwood mechanisms involving vibrationally excited adatoms are presented together with a criterion for establishing their relative contribution to the total reaction rate. Analogies of this multilevel ‘hot atom' (HA) model with recently employed two and three levels HA kinetic schemes are presented and discussed.