Molecular Structural Chemistry Laboratory (분자 구조 화학 실험실)

We investigates ionic clusters, assemblies of ions and molecules, using mass spectrometry. We couple electrospray ionization (ESI) with ion mobility spectrometry–mass spectrometry (IMS–MS) to generate weakly bound ionic clusters in the gas phase and to quantify collision cross sections (CCS), which provide conformational information of ionic clusters. By integrating CID/MSⁿ experiments with quantum-chemical calculations (DFT) and trajectory-method CCS predictions, we predict the structures and thermodynamic stability of ionic clusters and host-guest complexes including alkali halide ions, amino acids, saccharides, and N, O-donor ligands. Together, these measurements provide reproducible structural constraints that inform electrolyte design, ion transport, and supramolecular assembly across solution, interfacial, and gas-phase regimes. The structure–function relationship is a fundamental principle underlying all biological systems. Consequently, the study of the molecular structures of biological macromolecules, with a particular focus on proteins and nucleic acids, is essential for comprehending biological processes. Since the 20th century, the development of mass spectrometry (MS) has encompassed techniques such as electrospray ionisation (ESI) and matrix-assisted laser desorption/ionisation (MALDI), enabling the transfer of delicate biomolecules from solution into the gas phase. In our research, we couple MS with ion mobility spectrometry (IMS) to obtain additional information called the collision cross section (CCS), which reflects the surface area of biomolecules. This CCS has been demonstrated to serve as an indicator of structural preservation or unfolding. By employing it as an index, it is possible to interpret structural stability and features that were previou