  First-principle density-functional calculations have been applied to study
the interaction of molecular chlorine with the (111) plane of copper. Using
transition-state search method, we considered the elementary processes (Cl$_2$
dissociation, adsorption, diffusion, association and desorption) on the
chlorinated Cu(111) surface. A systematic study of possible desorption pathways
has been carried out for different species (Cl, Cl$_2$, CuCl, CuCl$_2$, and Cu)
at various chlorine coverage. As a result, we concluded that chlorine monolayer
irrespective of the coverage desorbs in the form of CuCl molecules from step
edges.
