Optical Control of Photogenerated Ion Pair Lifetimes: An Approach to a Molecular Switch

Science  25 Oct 1996:
Vol. 274, Issue 5287, pp. 584-587
DOI: 10.1126/science.274.5287.584


A prototype molecular switch is demonstrated that works on the principle that the local electric field produced by one photogenerated ion pair (D1+-A1) can influence the rate constants for photoinduced electron transfer and recombination in a second donor-acceptor pair (A2-D2). Two ultrafast laser pulses were used to control the rate of a photoinduced electron transfer reaction within a molecule that consists of two covalently linked electron donor-acceptor pairs fixed in a linear structure, D1-A1-A2-D2. This type of molecular architecture may lead to the development of electronic devices that function on the molecular length scale.