Switch turns molecular wire signal on and off

Abstract

By astutely varying the building blocks of molecular wires that transmit light energy, a team of chemists has devised a way to switch the signal on and off at will. Their new molecular optoelectronic gates are a step toward components that could be used to build future molecular-scale computers. Molecular photonic wires that absorb a photon of light at one end of an array of porphyrins, then emit a different photon at the other end, were developed a few years ago by chemistry professor Jonathan S. Lindsey and postdoctoral fellow Richard W. Wagner at Carnegie Mellon University, Pittsburgh (C&EN, Oct. 31,1994, page 5). Now, working with chemistry professor David F. Bocian's group at the University of California, Riverside, they have devised a way to interrupt transmission of the light energy by adding a magnesium porphyrin that can be selectively oxidized [ J. Am. Chem. Soc , 118,3996 (1996)]. If we are ever going to make molecular devices ...