Open Access

Dimitrios Tsitsonis

• A powerful technique to distinguish the enantiomers of a chiral molecule is the Coulomb Explosion Imaging (CEI). This technique allows us to determine the handedness of a single molecule. In CEI, the molecule becomes charged by losing many electrons in a very short period of time by interacting with the light. The repulsion forces between the positive charged particles of the molecule leads the molecule to break into parts-fragments. By measuring the three vector momentum of (at least) four fragments, the handedness observable can be determined. In this thesis, CEI is induced by absorption of a single high energy photon, which creates an inner-shell hole (K shell) of the molecule. The subsequent cascade of Auger decays lead to fragmentation. We decided to work with the formic acid molecule in this thesis. Two different experiments were conducted. The first experiment focused on exciting electrons to different energy states, while the second experiment focused on extracting directly a photoelectron to the continuum and measure the angular distribution of the photoelectron in the molecular frame. The primary goal was to search for chiral signal in a pure achiral planar molecule under the previous electron processes. The results of these findings were further implemented to two more molecules.
• Diese Dissertation widmet sich dem Thema Chiralität, Enantiomere, Anregung von Elektronen der inneren Schalen und Photoionisation. Die Arbeit beleuchtet die Wechselwirkungen und Auswirkungen dieser Phänomene auf molekulare Strukturen. Die Erforschung der Photoionisation beziehungsweise der Anregung und ihres Zusammenspiels mit der Chiralität hat zu bahnbrechenden Erkenntnissen geführt. Weiter wurden die Winkelverteilungen von K-Schalen Photoelektronen von Ameisensäure, Sauerstoff und Isopropanol in einem molekülfesten Bezugssystem untersucht...