Crawling Motion of Crystals on Solid Surfaces by Photo‐induced Reversible Crystal‐to‐Melt Phase Transition

The motion of objects has attracted attention from various research areas. In this chapter, mechanical motions such as crawling, swimming, and bending are described. These motions are achieved by the photoinduced crystal-to-melt phase transition found in azobenzene derivatives. Among them, the crawling motion of the crystal is intriguing because this motion is possibly used in a carriage vehicle to transport objects/chemicals on a solid surface without a flow channel.