Helium Droplet Mass Spectrometry

Abstract

Mass spectrometry is of paramount importance in many studies of pristine and doped helium droplets. Here, we attempt to review the body of work that has been performed in this field. Special focus is given to experiments conducted by the group of Paul Scheier at the University of Innsbruck. We specifically highlight recent studies of highly charged helium droplets and the successive development of pickup into highly charged and mass selected droplets.

Diamondoid ether clusters in helium nanodroplets

“…Subsequently, various clusters can form during this entrapment process and HNDs are therefore essentially small reaction chambers. [5][6][7][8][9][10][11][12][13] The binding energy released upon cluster formation is dissipated through the evaporation of helium atoms. As helium becomes superfluid at low pressures and near-zero Kelvin temperatures, properties like vanishing viscosity and high heat conductivity emerge, 14 making the helium aggregates a suitable medium for trapping weakly binding complexes.…”

Gas‐Phase Electronic Structure of Phthalocyanine Ions: A Study of Symmetry and Solvation Effects

“…Another well‐established method to study molecules in the gas phase at extremely low temperatures involves embedding them in helium nanodroplets (HNDs). [ 16 ] These droplets, composed of weakly bound helium atoms, serve as a cold matrix that captures any molecule it collides with. [ 17 ] The fundamental issue of micro‐solvation, which treats how the helium matrix affects spectroscopic features, has been extensively examined for H 2 Pc, primarily using fluorescence excitation and emission spectroscopy.…”

Nanostructured supramolecular networks from self-assembled diamondoid molecules under ultracold conditions

“…The highly non-polar medium of helium nanodroplets (HNDs) offers an opportunity to non-disruptively study weak intermolecular interactions. [6][7][8][9][10][11][12][13][14] By expanding gaseous helium in a high vacuum at cryogenic temperatures, 15,16 one obtains helium aggregates suitable for trapping introduced atoms and molecules. Cluster formation is a favorable process since the binding energy of aggregation can be dissipated through the evaporation of helium atoms.…”