Understanding how electrons are transported through single molecules, particularly π-stacked molecules, has important implications for molecular electronics and polymer and materials science. Electron transport through the initial building blocks of π-stacked systems has never been directly examined despite the many experimental artifacts attributed to these small interactions.

Makoto Fujita and co-workers, University of Tokyo, Japan, have measured the conductance of π-stacked aromatics where the π stack was sequentially increased from four to six stacked aromatic molecules. They were able to show that electron transfer occurs through the π-stacked system and could precisely calibrate the electron-transport distance for the first time. Only a moderate loss of conductance with increasing transport length was seen.

This could lead to the development of molecular wires where π-stacked aromatics provide the pathways for electron transport.

• Electron Transport through Single Molecules Comprising Aromatic Stacks Enclosed in Self-Assembled Cages
  M. Kiguchi, T. Takahashi, Y. Takahashi, Y. Yamauchi, T. Murase, M. Fujita, T. Tada, S. Watanabe,
  Angew. Chem. Int. Ed. 2011.
  DOI: 10.1002/anie.201100431