Photodissociation of a HCl molecule adsorbed on ice

This work is a two-dimensional study of the photodissociation of a HCl molecule adsorbed on a proton ordered hexagonal ice surface. We apply the multi-configuration time-dependent Hartree method to study the dynamics of the hydrogen photofragment. The calculated absorption spectrum exhibits structures which are related to a temporary trapping of the hydrogen between the Cl atom and the ice surface. The angular distribution of the emitted hydrogen shows structures which are attributed to a surface rainbow effect. Moreover the results indicate that the photodissociation of HCl can lead to a diffusion of the hydrogen fragment into an ice cavity.