My main field of interests are reactions of ions in the interstellar medium and planetary ionospheres. Since a multitude of chemical processes involving ions are proceeding without activation barriers, they are feasible under the cold conditions prevailing there. Although radical reactions have long been regarded as important in these environments and surface processes have recently emerged into the focus of attention of astrochemists, ionic processes are still regarded as crucial in the synthesis of many interstellar and circumstellar molecules. Especially dissociative recombination (in which an electron reacts with a cation and the reaction energy is dispersed through fragmentation of the intermediate neutral) is seen as the crucial final step in many pathways of interstellar molecule formation. The ion-storage ring CRYRING has allowed measurement of branching fractions and rate constants of such processes at the low relative kinetic energies prevalent I the interstellar medium and planetary ionospheres.
I also take keen interest in the chemistry of anions in space, which is now attracting a lot of attention due to the first detections of these species in dark clouds and circumstellar envelopes. The double-storage ring DESIREE, which is to be commissioned soon, will enable investigations into ion-ion reactions at very cold temperatures. I am looking forward to seeing the first results for this quite unexplored type of chemical reactions.
