TIFR
Department of Chemical Sciences
School of Natural Sciences

June 15, 2015 at 11.30 am in AG-80

Title : 

Physics and Chemistry at the Single-Molecule Level

Abstract :

Understanding and controlling electron transfer across metal/organic interfaces is of critical importance to the field of organic electronics and photovoltaics. Single molecule devices offer an ideal test bed for probing charge transfer and mechanics at these interfaces, allowing us to understand fundamental physics and chemistry at the single-molecule level. The ability to fabricate single molecule devices and probe their electronic characteristics reliably and reproducibly has enabled us to study and model their physical, electronic and chemical properties. In this talk, I will review the scanning tunneling microscope break-junction technique we use to measure conductance through single molecule junctions.1 I will discusshow we use this platform to measure secondary characteristics of such junctions such as thermopower2 and force,3 and present new results on our ability to create single-molecule rectifiers.

 

[1]          L. Venkataraman, J. E. Klare, C. Nuckolls, M. S. Hybertsen, and M. L. Steigerwald, "Dependence of single-molecule junction conductance on molecular conformation", Nature442, 904-907 (2006).

[2]          E. J. Dell, B. Capozzi, J. Xia, L. Venkataraman, and L. M. Campos, "Molecular length dictates the nature of charge carriers in single-molecule junctions of oxidized oligothiophenes", Nat. Chem.7, 209-214 (2015).

[3]          S. V. Aradhya, M. Frei, M. S. Hybertsen, and L. Venkataraman, "Van der Waals Interactions at Metal/Organic Interfaces at the Single-Molecule Level", Nat. Mat.11, 872-876 (2012).