Fast T‑Type Photochromic Crystals of Diarylbenzene

Photochromic
molecules are of great interest as light-driven molecular
switches in research fields of material and life sciences. In particular,
fast T-type photochromic molecules with half-life times of the thermal
back reaction (t1/2) on the order of milliseconds
can change not only their color but also their physicochemical properties
only under photoirradiation. Herein, we report fast T-type photochromic
crystals with the t1/2 on the order of
milliseconds composed of a diarylbenzene by utilizing intramolecular
CH–N hydrogen bonding interactions. Our results would lead
to novel photoresponsive crystalline materials whose color and physicochemical
properties can be modulated only under photoirradiation.