Hydrogen Bond-Modulating Luminescent Properties of Organic Cocrystal Materials

The collaboration of intermolecular interactions to form diverse organic cocrystal materials with a tunable property serves primarily for their application in optoelectronic devices and solid-state luminescent materials. Revealing the effects of intermolecular interactions, especially hydrogen bonds, on the degree of charge transfer and luminescence features of organic cocrystals is important, but they still remain elusive. Herein, five organic cocrystals with 1,2,4,5-tetracyanobenzene as the acceptor and naphthalene derivatives as the donors were constructed by varying the position and number of hydroxy substituents of the donor. Although the stacking structures were similar, these organic cocrystals showed different luminescent properties depending on the number and strength of the hydrogen bonds. These results revealed that the formation of hydrogen bonds played an important role in the degree of charge transfer and nonradiative transition. This study provided a facile strategy for tuning the optical properties of organic cocrystals, leading to the preparation of anticounterfeiting material for potential applications in material sciences.