SAMOP 2023 – wissenschaftliches Programm
MO 5.3: Vortrag
Dienstag, 7. März 2023, 11:30–11:45, F142
Optical Absorption and Photodissociation Properties of SinOm+ — •Taarna Studemund, Marko Förstel, Kai Pollow, Emil Mickein, and Otto Dopfer — IOAP, TU Berlin, Germany
The formation mechanisms of interstellar dust grains are still poorly understood. It is known, however, that these contain a significant amount of µm-sized silicate material . So far only silicon monoxide (SiO) is identified in the interstellar medium . We compare experimental data to quantum chemical calculations to understand photodissociation and optical absorption behavior, structures, and energies of possible SinOm+ molecules that are potential and promising precursors. The experimental setup relies on action spectroscopy via mass spectrometry and resonant laser photodissociation of size-selected SinOm+ clusters. These are generated via laser vaporization in a molecular beam expansion coupled to a quadrupole/time-of-flight tandem mass spectrometer and a broadly tuneable UV/VIS-OPO laser . Preliminary data reveal competing fragmentation channels, their appearance energies and branching ratios, and the abundance and stability of neutral fragments. We highlight especially the spectrum of Si3O2+ measured by photodissociation and discuss it in an astrophysical context.
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