5. Conclusion

Understanding, at the molecular level, the elementary processes involved in photochromism is a key challenge for fundamental research. Complementarity between organic chemistry, computational chemistry, ultra-fast spectroscopy and materials science is the key to continued innovation in terms of industrial applications. Indeed, the development of photochromic glasses based on organic molecules in the 1990s is still, in 2018, the only notable and widespread application of photochromic materials. However, photochromic materials are the subject of much research, as the photocommutation of many other properties (magnetic, mechanical, optical, surface) in addition to the variation of absorbance properties (color) can be extremely useful. The development of systems for photomodulating fluorescence emission via photochromism opens the way to applications such as high-density optical memories, or...