Photoinduced Switching in Self-Assembled Multilayers of an Azobenzene Bolaamphiphile and Polyelectrolytes

The reversible cis–trans photoisomerization of azobenzene and its derivatives has potential applications in optical data storage systems. But can the photoisomerization occur also in multilayers? It is shown that differences in photochemical activity can be ascribed to the different packing of azobenzene derivatives in the layers, free volume, such as illustrated in the Figure, being necessary to enable the photoisomerization to take place.