Optical model of dissociative chemisorption: H₂ on the (111), (110), and (100) faces of copper

The recently developed optical model of gas-surface scattering is applied to dissociative chemisorption of a hydrogen molecule on different faces of a copper crystal. In each case, a potential of mean force is employed to describe the real part of the scattering potential. The probability of dissociative chemisorption is studied as a function of crystal face, total collision energy, parallel momentum, initial orientation of the molecule with respect to the surface, and surface temperature. The optical model is able to provide excellent qualitative agreement with experimental observations and detailed theoretical calculations.