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How to utilize molecular vibration to tune triplet‐involved emissions in multiple states is highly challenging. Here, star‐shaped triphenylamine derivatives have been employed as model systems to understand how molecular vibration affects thermally activated delayed fluorescence (TADF) and room temperature phosphorescence (RTP) emissions in multiple states. Nonplanar, star‐shaped conformations allow molecules to generate appropriate vibrations in the solution state, facilitating vibronic coupling between their T1 and T2 states to generate effective TADF. More importantly, a relatively dispersed state can allow the molecules to efficiently vibrate in the solid state, and a crystalline environment further promotes a more efficient TADF. Lastly, by suppressing molecular vibration to inhibit the TADF, ultra‐long RTP was observed upon doping these molecules into polymers. These molecules can be used in information encryption and storage as well as bioimaging. [ABSTRACT FROM AUTHOR]

Developing radical emission at ambient conditions is a challenging task since radical species are unstable in air. In the present work, we overcome this challenge by coassembling a series of tricarbonyl‐substituted benzene molecules with polyvinyl alcohol (PVA). The strong hydrogen bonds between the guest dopants and the PVA host matrix protect the free radicals of carbonyl compounds after light irradiation, leading to strong solid state free radical emission. Changing temperature and peripheral functional groups of the tricarbonyl‐substituted benzenes can influence the intensity of the radical emission. Quantum‐chemical calculations predict that such free radical fluorescence originates from anti‐Kasha D2→D0 vertical emission by the anion radicals. The photoinduced radical emission by the tricarbonyl‐substituted benzenes was successfully utilized for information encryption application. [ABSTRACT FROM AUTHOR]