Fast, Reversible, and General Photomechanical Motion in Single Crystals of Various Azo Compounds Using Visible Light

Pseudostilbene-type single crystals exhibit ubiquitous, fast, and reversible photomechanical motion under visible-light irradiation. Push-pull substituents impart extremely rapid switching using just one wavelength of light by shortening the lifetime of the cis-form. This results in a bending motion in the microsecond regime. The influence of crystal density, thickness, and molecular orientation on optimization of the photomechanical effect is investigated.