Currently, our group is working to introduce ions into superfluid helium nanodroplets for complexation with neutral molecules. In a helium nanodroplet, an alkali cation may form a complex with any neutral molecule, allowing for the possibility of mass spectrometry without fragmentation, or high resolution infrared spectroscopy. To introduce alkali cations into helium nanodroplets low energy ions are focused into the helium nanodroplet beam path where they may be solvated by a droplet and detected. Previous sources used for this experiment consisted of wire filaments coated with a molecular sieve paste which had been saturated with an alkali metal salt. These sources had the ability to produce low energy ions, but could not produce large currents due to the limitations of using a doped filament. The achievement of higher ion currents of low energy alkali cations required the design of a custom built ion source.
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