A pseudorotaxane on gold: Formation of self-assembled monolayers, reversible dethreading and rethreading of the ring, and ion-gating behavior

Machinelike behavior - reversible dethreading and rethreading of a molecular bead - is demonstrated in a self-assembled monolayer (SAM) of a pseudorotaxane on gold. Furthermore, unprecedented ion-gating behavior associated with threading and dethreading is observed; the SAM blocks or allows the access of electroactive species to the electrode surface depending on the presence or absence of the threaded molecular bead (see picture).