About event
Molecular electronics is a fascinating field in which individual molecules placed between two nanoscale electrodes exhibit a series of quantum phenomena not present in conventional electronics. Molecular conductance studies have traditionally focused on gold electrodes. However, the distinct reactivity and electronic properties of other metals opens new opportunities to explore and utilize novel metal-molecule chemistry in single molecule circuits.
In this talk, I will focus on our recent efforts in creating and characterizing electronically transparent molecule-Ag bonds. I will describe the work carried out in my group using atomistic simulations based on DFT-NEGF, as well as STM break-junction RT experiments performed in an inert atmosphere glovebox by our colleagues. Halogen-functionalized alkanes spontaneously form Ag-molecule-Ag junctions but their measured conductance is ~30× lower than that of analogous molecules on Au electrodes, which form highly-conducting Au-C covalent bonds. Through a series of control experiments and DFT simulations, we establish the formation of Ag-molecule bonds involving O atoms. These Ag-O linkages lead to a lower conductance compared to junctions with direct covalent metal-molecule links.
Our work demonstrates that electrode linker groups for single molecule electronics are not constrained to those on gold, and that guiding principles for forming high- and low-conductance junctions with Au electrodes may not translate to other metal electrodes of increased technological relevance.
