A Wide Array of Photoinduced Motions in Molecular and Macromolecular Assemblies at Interfaces

Molecular and macromolecular assemblies have good "chemistry" with light. In the research of photochromic molecules and systems, the number of papers in the most recent 10 years exceeds the half of the whole past century. Photo-chromic molecules have been studied for their characteristic color changes. Although the importance in this line has not dimmed, other powerful areas have emerged in the last two or three decades. Much more attention has been drawn to light induced motions triggered by photoreactions utilizing molecular and polymer assemblies. Probably, this field is one of the most developing areas in advanced soft material research. This review article mainly deals with azobenzene and diarylethene as the photochroms, and systematically introduces light triggered dynamic processes taking place at interfaces. In terms of the feature size, the systems at interfaces, mesoscopic and microscopic level materials are particularly highlighted. Molecular design and understanding of interfaces are the key to realize smart motility properties in molecular and polymer assemblies.