Ejection of atoms upon self-trapping of an atomic exciton in solid argon

Molecular-dynamics calculations are perforemd to describe the sputtering (desorption) of solid argon induced by the formation and trapping of atomic excitons. Upon self-trapping, a cavity is found to form around the atomic exciton in the bulk and the excited atom is desorbed if it traps on the surface. The calculated shift in the atomic lines of the photoabsorption spectrum of the self-trapped species and cavity radius are sensitive to the choice of the potential describing the interaction between the excited atom and the ground-state atom. It is found that ground-state atoms are not ejected by atomic exciton trapping and the calculated kinetic energies of the excited atoms ejected, which are sensitive to both the potential and the crystal configuration, are of the order of or less than 0.1 eV.