A Model of a Switching Molecular Junction with a Ring-shaped Molecule

Abstract

To determine efficient molecular junction configurations for use in switches, we analyzed the conductance of a model representing a molecular junction with a ring-shaped molecule weakly connected with two one-dimensional electrodes, taking into account resonance and interference effects. We considered a model in which the center molecule changes in shape from a ring to a chain and the Fermi energy lies at the center of the molecular eigenstates. We discovered that requirements for switching, which include particular atomic contacts relative to the reaction site, single out the following two cases as the most effective junctions. The large conductance through a 4m-membered ring due to the resonance effect becomes small when the conduction path becomes a chain. A less-conductive 4m+2-membered ring in the off-resonance state is switched on by the resonance effect in the final chain-shaped path.