Unveiling One-to-One Correspondence Between Excited Triplet States and Determinate Interactions by Temperature-Controllable Blue-Green-Yellow Afterglow.

Phosphorescence of organic materials is highly dependent on intermolecular interactions, for the sensitive triplet excitons toward environment and aggregated structures. However, until now, relationship between phosphorescence and intermolecular interactions is still unclear for complicated influence factors and uncontrollable aggregated behaviors. Herein, taking temperature as the controlled variable, the afterglow can continuously change from blue to green, then to yellow, even achieve the white emission with deuteration process. It is mainly due to the hierarchical architectures of molecular aggregates with rational distribution of intermolecular interactions, as well as gradually unlocking process of interactions with different energies. Accordingly, the one-to-one correspondence between the determinate interactions and excited triplet states have been established, guiding accurate design of desirable phosphorescence materials by hierarchical control of aggregated structures.