Quantitative Evaluation of Photoinduced Bending Speed of Diarylethene Crystals

We investigated photoinduced crystal bending behavior of various photochromic diarylethenes. In all the diarylethene derivatives we used in this work, the relationship between the initial photoinduced bending speed and the crystal thickness was well explained by the easy-handled Timoshenkos bimetal model. Moreover, we proposed a quantitative analysis method to reveal the relationship between the bending speed and the molecular structure of diarylethenes. These results provide the quantitative evaluation method of the photoinduced crystal bending speed.