On the stopping of Sn1+ ions in molecular hydrogen gas

We investigate the stopping of energetic (0.13–3 keV) Sn1+ ions in molecular hydrogen gas using a combined experimental and modeling approach. Data on Snq+−H2 collisions in this energy range is sparse, limiting a complete atomistic understanding. Time-of-flight measurements employing retarding field analyzers are used to quantify pressure-dependent shifts in flight time of Sn1+ ions traversing H2 at pressures between 2×10−4 and 2×10−2 mbar. From these shifts, stopping cross sections are extracted as a function of ion energy. To interpret the measurements, a semi-classical collision model is developed, which incorporates interaction potentials derived from density functional theory and explicitly accounts for the molecular structure of H2. The modeled stopping cross sections are in good agreement with the experimental results. Compared with other work, our dataset falls within the range reported in the literature and occupies a central position within this range.

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