The Analytical Chemistry, Physicochemistry, and Ion Reactivity group (CAPRI) brings together extensive expertise in analytical chemistry, spectroscopy, ion activation, and reactivity. These skills are primarily centered around a transversal technique, mass spectrometry, used both as an analytical method (often coupled with separation techniques) and as a favorable environment for the controlled activation of ions. With a strong tradition of instrumental and methodological developments, the group manages three ICP platforms (CLIO, SMAS, and CERISES) and maintains a significant range of mass spectrometry and separation technique equipment. Two fundamental themes and two analytical themes are being developed: one focuses on interaction with photons, including the spectroscopy and reactivity of isolated ions, and the other two on analytical physicochemistry and bioanalysis. These combined expertise and resources enable the group to tackle a wide range of challenges, from the reactivity of isolated atomic ions to the structural characterization of protein assemblies. The group's work finds applications in fields such as medicine, organometallic catalysis, analytical chemistry applied to plasmas and cultural heritage objects, atmospheric chemistry, and even astrochemistry.