Understanding and controlling the orbital alignment of molecules positioned between electrodes is crucial within the design of practically-applicable molecular and nanoscale digital gadgets. The orbital alignment is extremely decided by the molecule-electrode interface. Dependence of orbital alignment on the molecular anchor group for single molecular junctions has been intensively studied; nevertheless, when scaling-up single molecules to giant parallel molecular arrays (like self-assembled monolayers (SAMs)), two challenges must be addressed: 1. Most desired anchor teams don’t type top quality SAMs. 2. It’s a lot more durable to tune the frontier molecular orbitals by way of a gate voltage in SAM junctions than in single molecular junctions. On this work, we studied the impact of the molecule-electrode interface in SAMs with a micro-pore machine, utilizing a not too long ago developed tetrapodal anchor to beat problem 1, and the mix of a single layered graphene high electrode with an ionic liquid gate to unravel problem 2. The zero-bias orbital alignment of various molecules was signalled by a shift in conductance minimal vs. gate voltage for molecules with totally different anchoring teams. Molecules with the identical spine, however a unique molecule-electrode interface, had been proven experimentally to have conductances that differ by an element of 5 close to zero bias. Theoretical calculations utilizing density practical principle help the traits noticed within the experimental knowledge. This work sheds gentle on the way to management electron transport throughout the HOMO-LUMO vitality hole in molecular junctions and will likely be relevant in scaling up molecular digital programs for future machine purposes.
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