Seminar by Marc Simon from Sorbonne University about post collision interaction, High-Resolution Double Core Hole Spectroscopy, Recoil effects after emission of a fast photoelectron and ultrafast electronic and nuclear dynamics are particularly magnified in the tender x-ray domain (2-10 keV). I will present an overview of the studies we started about 2 decades ago with results obtained with different original experimental setups our group has developed (Photoemission spectrometer, COLTRIMS, X-ray emission spectrometer and Auger-ion coincidence spectrometer).