Exploration of Gas-Phase Molecular Spectroscopy by Using a Cryogenic Ion Trap

Laser spectroscopy under cryogenic gas-phase conditions offers an ideal platform for probing intrinsic molecular properties with high precision by minimizing perturbations from external environments such as impurities, solvents, and counterions. Particularly, recently developed cryogenic ion trap-based techniques afford a distinct advantage in their broad applicability to a wide range of molecular systems. To further extend the scope of this powerful approach, we have applied it to the gas-phase characterization of host–guest complexes, hypervalent compounds, reaction intermediates formed in solution, and metal/molecular clusters. In this account, we present an overview of the experimental setups developed in our laboratory and highlight recent studies that uncover "hidden molecular functions" across these diverse systems.