The barrier shows giant variations
Published in "Nature Materials", the work of scientists from the Max Planck Institute, University of Trieste, King's College and EPFL provides the first local characterization of the potential barrier at the contact between a single molecule and a metal electrode. This has been achieved by combining scanning tunnelling spectroscopy and density functional theory calculations.
Contrary to the common belief of a uniform barrier, the experiments reveal giant variations of the work function on the sub-molecular scale. Based on these observations the authors have developed a novel scheme to engineer the molecular contacts with atomic precision. The results are of fundamental importance for possible applications of molecules in any electronic device where charge injection and extraction are relevant.