Azo compounds, imines and oximes E Z photoisomerization

The photophysical and photochemical properties of cyclic azo compounds, where Z E isomerization is suppressed by geometric constraints, are very sensitive to seemingly minor structural changes (Table 6.16). In contrast to 2,3-diazabicyclo[2.2.1] 

Photochromism has many potential and existing applications that take advantage of a change in colour or other physicochemical properties during the process, for example variable-transmission optical materials such as photochromic eyeglass or ophthalmic lenses that darken in sunlight (using spiropyran and spirooxazine systems in addition to 

Case Study 6.28 Supramolecular chemistry - photoresponsive crown ethers 

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