Photoinduced Memory Effect in a Redox Controllable Bistable Mechanical Molecular Switch

Something to remember: A rotaxane could be operated as a bistable memory element under kinetic control (see picture). Data was written on the molecule by an oxidation stimulus and locked by UV light irradiation. After the writing session, the oxidized species was reduced back to the original form without losing the written data for a few hours. Light irradiation also protects nonoxidized rotaxanes from accidental writing.