Scientific Achievement
In this work, we observe highly efficient intermolecular charge transport between stacked pyridinium dimers inside a synthetic host (cucurbit[8]uril, CB[8]) using single molecule techniques.
Significance and Impact
This work provides a new understanding of intermolecular charge transport in π-stacked dimeric structures with well-defined stacking geometries using supramolecular assembly.
Research Details
- Extensive physical and chemical characterization shows that different types of pyridinium guest molecules dimerize into the cavity of CB[8] in a head-to-tail geometry with high binding affinity and compact π–π stacked structures.
- Single-molecule conductance experiments directly show that intermolecular conductance through pyridinium dimers is comparable to the intramolecular conductive pathway.
- Control experiments with a structural homolog of the host molecule (CB[7]) reveal that the host molecule does not directly participate in charge transport.
- DFT simulations show that pyridinium molecules undergo planarization upon dimerization inside the host cavity with large electronic coupling, facilitating efficient charge transport.
