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We report the study of the visible absorption spectroscopy of non-volatile cations trapped in the gas phase in a RF Paul trap. Absorption spectra of individual polycyclic aromatic hydrocarbons (PAHs), fullerene $C60$ or other drug/biological cations are recorded by monitoring the photofragmentation process through resonance enhanced multiphoton dissociation (REMPD). The combination of the versatility of the ion trap as a mass spectrometry and mass selection technique and the molecular conformation selectivity of laser spectroscopy make the apparatus a powerful tool for direct sampling analysis. It also provides access to information on the process and dynamics of the photo-induced fragmentation.