Electro-Engines (WP3)

The main task of workpackage 3 is the synthesis of a rotaxanes able to work as an oscillatory machine at surfaces. The rotor (a macrocylic ring) and the stator (a molecular thread) are linked together via a transition metal. The ring incorporates two different coordinating sites, a bi- and terdentate site. The thread incorporates one bidentate site.
The position of the ring on the axis will be determined by the oxidation state of the metal, which can be electrochemically monitored. A thick filament ended by a voluminous moiety, such as a porphyrin, is attached to the ring. The axis of the rotaxane is ended at each end by functionalities which will allow the attachment of the machine onto a gold surface, in form of self-assembled monolayers.
The operation of the machine will be triggered the potential of the host surface. The spinning of the filament, i.e. the rotor, will be investigated by scanning probe microscopy or by optical methods