Core-ionized states and spectra of Be and Mg dimers

The computed core spectra of Be and Mg dimers exhibit interesting nonatomic features. The spectra are analyzed and related to the underlying core-ionized states and their potential energy curves. Band shapes of the core-level spectra of the dimers are shown to be sensitive to changes of the interatomic distances. An analysis of the spectra computed at various distances reveals interesting details of the evolution of the spectra from a superposition of the respective atomic ones obtained at the dissociation limit to the spectra of the dimers. The vibrationally resolved spectra of the transitions from the ground to the main core-ionized states are computed as well.