28 January 2022

Séminaire ICP – Daniela Ascenzi – vendredi 28 janvier à 14h

Séminaire de Daniela Ascenzi (Dept. Physics, University of Trento ITALY)

Le vendredi 28 janvier 2022 à 14h

"Ion-molecule reactions of astrochemical relevance"

Ion-induced processes have long been regarded as playing a pivotal role in shaping the chemistry of the interstellar medium, and of the atmospheres of planets and their satellites. During the processes of star formations, leading from a dense and cold cloud to a fully developed planetary system, reactions of ions (as well as radicals) have been invoked as intermediate steps in the build-up of complex organic molecules (COMs) which can act as building blocks in the formation of prebiotic molecules and could be eventually delivered to planetary surfaces by impacts with comets and asteroids. On the other hand, reactions of the most abundant atomic and molecular dominate the destruction of the vast majority of COMs. For complex ions little experimental information is available on the reactivity and, in most cases, guesses based on “common sense” and chemical analogies are used for modelling the chemistry of such environments.

Our contribution is in the laboratory measurements of kinetic parameters (cross sections, branching ratios and their dependences on collision energy) for the reaction of charged molecules with neutrals, by using tandem mass spectrometric techniques and RF octupolar trapping of parent and product ions. After a general introduction to the topic, I will focus on the isomer selected reactivity of some N-containing ions, a project carried out in collaboration with the ICP group at CNRS and Paris-Saclay University [1-3]

References

[1] V. Richardson, C. Alcaraz, W.D. Geppert,  M. Polasek, C. Romanzin, D. Sundelin, R. Thissen, P. Tosi, J. Zabka, D. Ascenzi Chem.Phys.Lett. 775, 138611 (2021) https://doi.org/10.1016/j.cplett.2021.138611

[2] D. Sundelin, D. Ascenzi, V. Richardson, C. Alcaraz, M. Polasek, C. Romanzin, R. Thissen, P. Tosi, J. Zabka , W.D. Geppert Chem.Phys.Lett. 777, 138677 (2021) https://doi.org/10.1016/j.cplett.2021.138677

[3] V. Richardson, D. Ascenzi, D. Sundelin, C. Alcaraz, C. Romanzin, R. Thissen, J.-C. Guillemin, M. Polasek, P. Tosi, J. Zabka, W.D. Geppert Frontiers in Astronomy & Space Science 8, 752376 (2021) doi: 10.3389/fspas.2021.752376

28 January 2022, 14h0015h00
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