Experimental Approaches for Controlling Current Flowing through Metal-Molecule-Metal Junctions

Electron-transfer processes through molecular systems have attracted much attention over the past fifty years. The traditional experimental approach for studying these processes is based on measuring the electron-transfer rate in D–B– A supramolecular systems between electron donor (D) and acceptor (A) units that are covalently linked through a molecular bridge (B). In the late 1990s, a combination of nanotechnology, scanning probe microscopy, and methods to form functional connections to metal surfaces, triggered the fabrication of different kinds of metal–molecule(s)–metal junctions and opened the door to a new experimental approach to measure electron-transfer processes through molecules as current flowing between two electrodes. By using a combination of sophisticated and expensive techniques, difR ES EA R C H N EW S