Sarah Burke

Professor Sarah Burke, University of British Columbia. Electronic landscapes in organic semiconductor nanostructures: mapping states for charge transfer at sub-molecular scales using pixel-by-pixel scanning tunnelling spectroscopy.  R.B. Woodward Lectures in the Chemical Sciences, Physical Chemistry Seminar.Abstract:  The inter- and intra- molecular energy transfer underlying applications in organic electronics, optoelectronics and catalysis relies on both the spatial distribution of electronic states and their energy level alignment across interfaces at the molecular scale.  We use scanning tunnelling microscopy and spectroscopy, operated in a spectroscopic mapping mode that allows us to visualize the structure and spatial distribution of the electronic states across molecular nano structures.  I will describe two model systems we have been investigating: surface-bound Fe-terpyridine coordinations polymers, and nanoscale clusters of the prototypical organic semiconductor PTCDA.  In each of these examples, the sub-molecular resolution spectroscopy yields high resolution energetic and spatial information that can be used to understand the local electronic landscape and directly relate this to the local molecular structure.