Green Light Powered Molecular State Motor Enabling Eight-Shaped Unidirectional Rotation

Molecular motors convert external energy into directional motions at the nanoscale. To date unidirectional circular rotations and linear motions have been realized but more complex directional trajectories remain unexplored on the molecular level. In this work we present a molecular motor powered by green light allowing to produce an eight-shaped geometry change during its unidirectional rotation around the central molecular axis. Motor motion proceeds in four different steps, which alternate between light powered double bond isomerizations and thermal hula-twist isomerizations. The result is a fixed sequence of populating four different isomers in a fully unidirectional trajectory possessing one crossing point. This motor system opens up new avenues for the construction and mechanisms of molecular machines and will therefore not only expand the toolbox of responsive molecular devices but enable unprecedented applications in the field of miniaturized technology in the future.