The dissociation in the core-excited SF 6 molecule additionally leads to low-energy losses near the elastic line. These are associated with population of the vibrational levels in the ground state potential energy surface. Fig. shows a comparison between experimental and calculated RIXS spectra for vertical and horizontal polarization. It can be seen that the experimental band is asymmetric and extends for about 4.5 eV, however no vibrational peaks can be distinguished, as experimental resolution is limited. The theoretical RIXS spectrum, computed within a one-dimensional wave packet model, evidences a long progression of vibrational states associated with the S-F stretching vibration. We expect that future high-resolution measurements could resolve this progression, but it should also be considered that additional vibrational modes not included in our simulations could lead to additional peaks.