Visible-Light-Activated Molecular Switches.

The ability to influence key properties of molecular systems by using light holds much promise for the fields of materials science and life sciences. The cornerstone of such systems is molecules that are able to reversibly photoisomerize between two states, commonly referred to as photoswitches. One serious restriction to the development of functional photodynamic systems is the necessity to trigger switching in at least one direction by UV light, which is often damaging and penetrates only partially through most media. This review provides a summary of the different conceptual strategies for addressing molecular switches in the visible and near-infrared regions of the optical spectrum. Such visible-light-activated molecular switches tremendously extend the scope of photoswitchable systems for future applications and technologies.