Negative differential resistance and rectifying behaviors in atomic molecular device with different anchoring groups

The electronic transport properties of molecular wires made of carbon atomic chains (triynes) capped with benzene are investigated using nonequilibrium Green’s function in combination with density functional theory. The results show that the anchoring group plays a crucial role in determining the overall conductivity of the molecular junction. Negative differential resistance can be observed when the molecular wire contacts Au electrodes through a dithiocarboxylate linker on both sides, while the rectifying performance is observed when the molecular wire contacts Au electrodes through a thiol linker on one side and with a dithiocarboxylate anchoring group on the other. The mechanisms are suggested for these behaviors.