Exploring the excited state photochemistry of aromatics: competing deactivation processes in deprotonated anions and the influence of functional groups on photostability

Aromatic species in a variety of charge states play key roles in the physical chemistry of environments as diverse as the interstellar medium, the Earth’s atmosphere and biological cells. In this seminar, I will present the most recent results obtained by our team in the PIIM laboratory, Marseille, where we characterise simple aromatic species using UV-visible action spectroscopy in a cryogenic ion trap. A particular focus will be on the deactivation processes of photoexcited deprotonated aromatic anions, more specifically the competition between anionic and neutral relaxation pathways. I will introduce a novel experimental technique we use to study neutral photoproducts of ions and show that the presence and position of functional groups and heteroatoms can significantly influence the photostability of the anion as well as the stability of its neutral photoproducts.