- Molecules often do not play alone, but assemble together via either covalent linkage or non-covalent interactions to have specific structures and functions. Examples of these molecular clusters and/or aggregates include various organic/inorganic self-assemblies, metal and/or semiconductor nanoclusters, oligomeric biomolecules, and so on.
- In our researches, we emphasize the importance of the structures and interactions in the intermediate clusters and aggregates. The reasons are following: The structures of the final cluster or assembly often depend highly on 1) the size and shape of intermediate clusters/aggregates, 2) the covalent and non-covalent interactions which are formed or broken during the formation of intermediates, and 3) the interactions between intermediate species with surrounding environments such as solvent and surface ligands. Therefore, obtaining insight into the structure of those intermediate clusters/aggregates is of great importance, because it enables to understand the detailed mechanisms and driving forces of assembly process and further allows for controlling and manipulating the structures and functions of molecular clusters/assemblies.
- However, the chemistry of those intermediate clusters and aggregates have not been explored intensively. It is mainly due to their intrinsic complexities and transient nature. Firstly, they usually exist in a wide distribution of cluster size and aggregation states. Secondly, an enormous number of structures and conformations are possible for each cluster or aggregation state. Thirdly, the cluster growth and the aggregation process usually involve a series of complex structural and conformational transitions. Unfortunately, conventional condensed-phase analytical methods for the structural study often have limitation in studying those clusters and aggregates, because they only yield ensemble averaged results over a wide distribution of clusters/aggregates as well as conformational isomers, and it is extremely hard or even impossible to separate a specific size of cluster or aggregate from the distribution.
- For those reasons, the development and application of new and complementary experimental approaches to determine the structural elements and interactions in the specific individual molecular clusters/aggregates is needed. This requires the proper isolation of each cluster/aggregate of specific size and conformation and the structural analysis using spectroscopic methods. Therefore, we are using a gas-phase experimental approach which combines mass spectrometry (MS), ion mobility spectrometry (IMS), molecular ion optical spectroscopy, and theoretical methods. This combination enables to investigate the structures and interactions of the isolated individual atomic and molecular cluster/aggregate.
국가
대한민국
소속기관
포항공과대학교 (학교)
연락처
054-279-2341 http://scimms.postech.ac.kr/
책임자
서종철 jongcheol.seo@postech.ac.kr