Resonant inelastic X-ray scattering on atoms and simple molecules in the tender X-ray region

► A curved crystal spectrometer for gas-phase RIXS studies in the tender X-ray range. ► Resonant inelastic X-ray scattering on Xe atoms around their L3 absorption edge. ► KM double photoexcitations in Ar studied via high resolution XES spectroscopy. ► Resonant inelastic X-ray scattering on HCl molecule near the Cl K edge. ► Electronic state interferences in KL RIXS spectra of HCl molecule.