Organic crystals for second harmonic generation switching based on anil photochromes

In photochromic materials, we demonstrated that non-linear optical (NLO) properties such as second harmonic generation (SHG) can be switched reversibly by alternate UV and visible irradiations. We report here on the design of materials fulfilling the prerequisites for SHG activity (push-pull and acentric space group) and photochromic properties. Photochromic and NLO properties of a series of anils are presented, along with the ability of some of them to switch SHG.