Supermolecular excitation antenna: Ordered energy funnel

The development of exciton probes, including single molecule probes, inspired the design of a single molecule lens or energy antenna, based on phenylacetylene dendrimers, the largest so far synthesized structurally ordered molecules. To demonstrate the energy-funnel model we synthesized partial dendrimeric wedges with an excitation acceptor, a perylene derivative pendant, at the locus. As expected, the energy transfer from the large antenna (39 phenyl groups) increases the yield of the yellow perylenic emission by three orders of magnitude for a given excitation wavelength. Overall, such a photonic subwavelength antenna or nano-lens may play a role in developing molecular excitonics, including luminescent optical nanoprobes, scanning exciton tunneling microscopy and nanometer scale fiber-optic chemical and biochemical sensors.