Cis-trans photoisomerisation

Bortolus, P., and Monti, S. (1979). Cis-trans photoisomerisation of azobenzene. Solvent and triplet donor effects. J. Phys. Chem. 83, 648-652. 

Cis-trans photoisomerisation in organic molecules is a well-studied process. Photoisomerisation of alkenes and azobenzenes forms a basis for applications ranging from information storage to molecular motors [3]. Usually, due to absorption properties of the organic compounds, UV light is required to initiate photoisomerisation. Attachment of the photoisomerisable units to transition metals opens up a route to use low energy, non-destructive visible light to initiate isomerisation via CT states. 

Inoue, Y., Takamuku, S., Kunitomi, Y, and Sakurai, H., Singlet photosensitization of simple alkenes. Part 1. cis-trans Photoisomerisation of cyclooctene sensitized by aromatic esters, /. Chem. Soc., Perkin Trans. 2, 1672,1980. 

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