piwik-script

Deutsch Intern
    Research group of Ingo Fischer

    Spectroscopy and dynamics of reactive species

    Reaction Dynamics of Radicals, Biradicals and Carbenes

    We are particularly interested in hydrocarbon radicals and carbenes that appear as intermediates in combustion, hydrocarbon cracking, atmospheric and astrochemistry. The issues we are most interested in are the electronic strucuture of radicals, the kinetics (i.e. rates) and dynamics (i.e. mchanistic details) of their unimolecular reactionsthe structure and reactivity of their cations. Due to the high reactivity we carry out our experiments in molecular beams in order to avoid collisions. Radicals are generated by flash pyrolysis: A suitable precursor seeded in a rare gas  is expanded through a pulsed valve with an electrically heated SiC tube mounted at the exit. If the conditions are chosen just right, the thermochemically most labile bond in the precursor is cleaved and a clean and intense radical beam is obtained. Now the intrinsic properties of the radicals are spectroscopically studied. To obtain a complete picture of a radicals we assemble results obtained by various spectroscopic methods, like multiphoton ionization, photoelectron spectroscopy, time-resolved spectroscopy and photofragment spectroscopy. 

    The project is supported by the "Deutsche Forschungsgemeinschaft".

    Coworker:  Dr. Deb Pratim Mukhopadhyay, Christian Matthaei, Lea Bosse

    Selected publications:

    A. Röder, J. Petersen, K. Issler, I. Fischer, R. Mitric, L. Poisson,
    Exploring the Excited-State Dynamics of Hydrocarbon Radicals, Biradicals, and Carbenes Using Time-Resolved Photoelectron Spectroscopy and Field-Induced Surface Hopping Simulations
    J. Phys. Chem. A 123, 10643 (2019)
    http://dx.doi.org/10.1021/acs.jpca.9b06346

    K. Issler, A. Röder, F. Hirsch, L. Poisson, I. Fischer, R. Mitric, J. Pedersen
    Excited state dynamics and time-resolved photoelectron spectroscopy of para-xylylene
    Faraday Disc. 212, 83 (2018)
    https://doi.org/10.1039/C8FD00083B

    M. S. Schuurman, J. Giegerich, K. Pachner, D. Lang, B. Kiendl, R. MacDonell, A. Krueger, I. Fischer
    The Photodissociation Dynamics of Cyclopropenylidene, c-C3H2
    Chem. Eur. J. 21, 14486 (2015)
    https://doi.org/10.1002/chem.201501624

    C. Alcaraz, I. Fischer, D. Schröder
    Radical Chemistry in the Gas Phase In: Encylopedia of Radicals in Chemistry,
    Biology and Materials, Ed. A. Studer & C. Chatgilialoglu (John Wiley & Sons, Chichester, 2012), 477-502
    http://dx.doi.org/10.1002/9781119953678.rad011