Collision Induced Dissociation in Biomolecule Cations
Molecular Physics seminar
Monday 11 January 2016
to 11:00 at
Linda Giacomozzi (Atomic Physics)
We have recently measured absolute cross sections for knockout of single carbon atoms in collisions between PAH ions and noble gases   . The knockout process in PAH molecules can result in highly reactive fragments, which are not formed in statistical fragmentation . These fragments may be key intermediate steps in the formation of larger molecules in the interstellar medium. The knockout mechanism is expected to be important for any molecular system with a center-of-mass collision energy around 100 eV and down to the threshold energy for this process. PAHs are ideal for studying these processes as they have a planar rigid structure and the single carbon loss is strongly suppressed when the fragmentation is statistical   . Biomolecules on the other hand are typically non-planar and more fragile systems, and it is more complicated to distinguish non-statistical fragmentation processes from statistical ones.
In this work, we have studied collisions between biomolecular ions and noble gas atoms. The experiments were carried out with the aid of a single pass collision setup, which is a part of the DESIREE facility   at Stockholm University. We will present preliminary results on first Collision Inducted Dissociation experiments with biomolecules (Adenosine 5’-monophosphate, Adenine and Adenosine) at a center-of-mass energies of about 100 eV. We will also present early results from an experiment on porphine ions in the same energy range.
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