Control of the rectifying effect and direction by redox asymmetry in Rh 2 -based molecular diodes.

Four asymmetrical self-assembled monolayers (SAMs) consisting of two subunits with different Rh2 building blocks present a pronounced rectifying behavior. The rectification ratio (RR) increases on increasing the redox potential difference between the two Rh2 subunits, and the rectifying direction can be reversed by reordering the subunits in the assembly.