Estimating single molecule conductance from spontaneous evolution of a molecular contact

We present an original method to estimate the conductivity of a single molecule anchored to nanometric-sized metallic electrodes, using a Mechanically Controlled Break Junction (MCBJ) operated at room temperature in liquid.

We record the conductance through the metal / molecules / metal nanocontact while keeping the metallic electrodes at a fixed distance.

Taking advantage of thermal diffusion and electromigration, we let the contact naturally explore the more stable configurations around a chosen conductance value. The conductance of a single molecule is estimated from a statistical analysis of raw con-ductance and conductance standard deviation data for molecular contacts containing up to 14 molecules. The single molecule conductance values are interpreted as time-averaged conductance of an ensemble of conformers at thermal equilibrium.

Read the article : https://hal.archives-ouvertes.fr/hal-01586755