Cosmic chemistry of complex aromatic molecules

Tuesday 23 April 2024, 4:30 pm
PhD student
D.B. Rap
prof. dr. B. Redlich
dr. S. Brünken

Temperature and density can differ by several orders of magnitude in different environments in outer space. The chemistry that unfolds in certain cosmic environments can therefore be quite unique. Infrared emission signals from space, for example, reveal the presence of large polycyclic aromatic hydrocarbons (PAHs) and indicate that PAHs play a major role in the chemistry of the interstellar medium (ISM). However, astrochemical models cannot yet predict all observed molecules and their numbers. This is partly due to lack of knowledge of reaction pathways. Ion-molecule reactions that form large PAHs, for example, have not yet been sufficiently studied, and are not used in models describing the formation and destruction mechanisms of PAHs. In this PhD thesis, we show that infrared action spectroscopy, among others, can be used to study in detail the formation and fragmentation chemistry of aromatic molecules. This technique makes it possible to gain insight into the chemical processes by determining the molecular structures of reaction products and fragments. The examples in this PhD thesis show that this chemistry is often more complex than previously thought.

Daniël (1995) obtained a Master's degree in Chemistry from Radboud University with a specialisation in Physical Chemistry in 2019. He then started his PhD at the HFML-FELIX laboratory, where he conducted research on reaction mechanisms of aromatic molecules that can occur in space.