Photo-mechanical azobenzene cocrystals and in situ X-ray diffraction monitoring of their optically-induced crystal-to-crystal isomerisation

We demonstrate the first supramolecular cocrystallisation strategy for generating crystalline azobenzene materials with a range of photo-mechanical and thermochemical properties: from those that exhibit isomerisation without any change in crystal shape to those that undergo a crystal-to-crystal cis – trans isomerisation accompanied by large scale bending.