Out-of-focus spatial map imaging of magnetically deflected sodium ammonia clusters

Abstract

This paper introduces out-of-focus spatial map imaging (SMI) as a detection method for magnetic deflection of molecular/cluster beams, using Na_m(NH₃)_n to illustrate its capabilities. This method enables imaging of the complete spatial distribution, simplifying measurements and allowing for cluster-size-resolved analysis by shifting away from traditional in-focus SMI conditions. Incorporating out-of-focus SMI with TOF-MS and velocity map imaging into a single setup allows for direct assessment of clusters' magnetic moments without needing to pre-select velocities. Key findings include a slower relaxation for Na(NH₃)₄ compared to Na(NH₃)₃ and Na(NH₃)₅, unexpectedly high deflection for larger clusters up to Na(NH₃)₉, hinting at changes in cluster dynamics as the first solvation shell closes. The study also covers the first measurements of Na₂(NH₃)₁ and Na₃(NH₃)_n, showing distinct deflection behaviors and underscoring the improved capabilities of the new detection method.