Deutsch Intern
Research group of Ingo Fischer

Infrared spectroscopy

IR-UV-spectroscopy with the free electron laser FELIX

Small resonance-stabilized radicals are intermediates in the formation of polycyclic aromatic hydrocarbons (PAHs) in reactive environments such as combustion processes. Similar reactions also lead to the formation of PAHs in the interstellar medium. IR/UV ion dip spectroscopy in a supersonically cooled free jet is an excellent method to investigate these reactions in a high-temperature (pyrolysis) flow reactor, because it combines the structural sensitivity of infrared radiation with the mass selectivity of UV light. Since an intense IR source is needed, the experiments are conducted at the free electron laser laboratory FELIX at the Radboud University, Nijmegen, The Netherlands. We are also investigating dimers of nitrogen-containing PAH (PANH) to elucidate their intermolecular interactions.

We also operate a Bruker IFS-120 FT-Spectrometer to record IR spectra in high temperature multi path gas cell as well as Raman spectra of liquids and solids.



Recent publications:

1. Tobias Preitschopf, Florian Hirsch, Alexander K. Lemmens, Anouk M. Rijs, Ingo Fischer
The gas-phase infrared spectra of the 2-methylallyl radical and its high-temperature reaction products
Phys. Chem. Chem. Phys., 2022, 24, 7682-7690

2. Florian Hirsch, Ingo Fischer, Sjors Bakels, Anouk M. Rijs
Gas-Phase Infrared Spectra of the C7H5 Radical and Its Bimolecular Reaction Products
J. Phys. Chem. A 2022, 126, 16, 2532–2540

3. Florian Hirsch, Kai Pachner, Ingo Fischer, Kevin Issler, Jens Petersen, Roland Mitric, Sjors Bakels, Anouk M. Rijs
Do Xylylenes Isomerize in Pyrolysis?
ChemPhysChem, 2020, 21, 1515-1518.