Femtosecond Optical Control of Charge Shift within Electron Donor--Acceptor Arrays: An Approach to Molecular Switches

摘要

The preparation and study of molecules for potential use as switches and wires in electronic or optoelectronic devices are areas of active research. Energy and electron transfer processes within molecules can take place on a femtosecond time scale. Thus, it may be possible to produce molecular electronic devices that respond equally rapidly. Molecular switches that employ optically-controlled, reversible electron transfer reactions may possess both speed and photostability advantages over molecular switches based on photochemical changes in molecular structure. An important criterion for a molecular switch is the ability to rapidly control the "states" of the switch. In this pager we report the two-pulse femtosecond election transfer dynamics of a donor--acceptor(l) dyad, 1, and a donor--acceptor(l)--acceptor{2) triad, 2, in which an initial femtosecond laser flash is used to produce an ion pair, whose subsequent fate is controlled by a second femtosecond laser flash.