Cryo Kinetics of $$N_2$$ Adsorption to Isolated Cationic Iron Clusters and Cryo IR Spectroscopy of the $$N_2$$ Adsorbates

• This thesis comprises investigations on the interaction of $$N_2$$ adsorbate molecules with size-selected iron metal clusters under cryo conditions. All investigations were performed at the customized fourier transform ion cyclotron resonance (FT-ICR) mass spectrometer FRITZ. This setup serves a laser vaporization (LVAP) source to generate the investigated iron cluster ions. Cryo kinetic studies investigate the stepwise $$N_2$$ adsorption on size selected $$Fe_n^+$$ clusters under well-defined isothermal conditions. The adsorption behavior and the adsorption limits lead to information about the cluster structure and its reactivity. By coupling a tunable IR laser in the ICR cell, it is possible to perform cryo infrared photon dissociation (IR-PD) spectroscopy experiments. This provides information on binding motifs of the $$N_2$$ adsorbates and the cluster structure. Combining both methods with quantum chemical calculations via density functional theory (DFT) substantiates the experimental results and deepens the fundamental insights into the cluster structure, their reactivity, and the metal-adsorbate bonding.