In this work we investigated the competition between the local Auger decay and core-level interatomic Coulombic decay (ICD) processes in core ionized rare-gas dimers. We computed the respective partial decay widths for the 4d vacancy in Xe-2, XeKr, and XeAr, as well as for the 3d vacancy in Kr-2.
We found that the efficiency of ICD is strongly increased with decreasing interatomic distance and decreasing energy transfer in the decay step. The ICD-to-Auger ratio in the Franck-Condon region, where the decay occurs, is at most 0.26%.
However, it reaches a few percentage points in larger clusters and becomes amenable for experimental observation. The small value of the branching ratio is due to large interatomic distances in the dimers (4-4.4 angstrom).
Our results also indicate, in accordance with previous measurements, that in hydrogen-bonded and microsolvated clusters, where the distances between the monomers are 2-3 angstrom, core-level ICD should become an important pathway for charge redistribution following the absorption of hard x-rays.