Figure 6: Potential interesting photochromic molecules.

These molecules have not been combined so far with carbon-based nanomaterials, which can be used for specific applications. Intramolecular transfer of phenoxyquinone for sensing (ref. 130). Photo-induced radical formation of biindenylidenediones (ref. 131) or photo-induced valence tautomerization of cobalt complexes (ref. 132) for spintronics. The three examples proposed represent basic chemical structures, which can be possibly redesigned with different substituents.