Eventually, the electronics will consist of individual molecules connected together by “molecular electric son, presenting themselves as one long molecule. But before designing such circuits, researchers need to understand how electric current flows through this type of thread. For if the macroscopic scale, the ability to carry electric current, that is to say, the conductance varies linearly with the length and the wire, across a molecule, this rule no longer applies. Hence the need to measure the electric current passes through a single molecular wire connected to two electrodes and determine how it varies with the length of the wire. Details as to date, all experimental studies focused on short son, a few nanometers, or were based solely on statistical measures.
Developed by researchers at the Free University of Berlin, in collaboration with their counterparts from the Center for Material Elaboration and Structural Studies (CEMES) of the CNRS in Toulouse and the Humboldt University of Berlin, a clever experiment performed under a scanning tunneling microscope, has characterized a one of the polymer chains of known length, up to 20 nanometers. But the results, published in the journal Science of 27 February, confirm what theory predicts, that the ability to conduct electrical current decreases exponentially with the length of the wire.