Modélisation d’agrégats d’hydrocarbures aromatiques polycycliques et d’eau : croissance et dissociation. – (Héloïse Leboucher / LCPQ / Thèse). – 7/11/2024, 14H00

Soutenance de thèse

Héloïse Leboucher LCPQ, Salle de conférence, 3R4

Summary:
Polycyclic aromatic hydrocarbons (PAHs) are a family of molecules that present several research interests, especially in astrochemistry. Interdisciplinary studies between experiment, theory and astronomic observations are mandatory to gain insights into the physical and chemical processes in which they are involved. New observations made by the James Webb Space Telescope (JWST) reveal that PAHs and water are present in the same interstellar region. Thus, this thesis focuses on the theoretical study of mixed PAH-water clusters, where the PAH of interest is the pyrene (C16H10). It addresses two main issues: (i) their structural, energetic and spectroscopic properties whether the systems are neutral or charged, and (ii) their growth and dissociation processes in the protonated case. To handle these large and complex systems and be able to run intensive simulations, the chosen method for the electronic structure calculations is the Density Functional based Tight-Binding method (DFTB), as implemented in the deMonNano code. This thesis work provides new and relevant molecular data that should contribute to improving the description of gas-grain interactions and be used to feed astrophysical models.

Jury composition:

• Céline Toubin (Université de Lille)
• Cyril Falvo (Université Paris Saclay)
• Ludovic Biennier (Université de Rennes)
• Sabine Morisset (Université Paris Saclay)
• Christine Joblin (Université de Toulouse)
• Aude Simon (Université de Toulouse)
• Mathias Rapacioli (Université de Toulouse)