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.

A new method for calculating internal conversion rate constants (kIC), including the anharmonic effects, and using the lagrangian multiplier technique, is proposed. The deuteration effect on kIC was investigated for...

This work describes as ynthetica pproachw here an on-planar aromatic heterocyclic [7]helicene is compressedt oy ield ah etero[8]circulene containing an inner antiaromatic cyclooctatetraene (COT) core. This [8]circulene consists of four benzene rings and four heterocyclic rings, and it is the first heterocyclic[ 8]circulenec ontaining three differenth eteroatoms. The synthetic pathway proceeds via at he flattened dehydro-hetero[7]helicene, which is partially ah elicene and partially ac irculene:i ti s non-planar and helically chiral as helicenes, and contains a COT motif like [8]circulenes. The antiaromaticity of the COT core is confirmed by nucleusi ndependent chemical shift (NICS) calculations. The planarizationf rom ah elically p-conjugated[ 7]helicene to af ully planar heterocyclic [8]circulene significantly alterst he spectroscopicp roperties of the molecules.P ost-functionalization of the [7]helicenes and the [8]circulenes by oxygenation of the thiophene rings to the corresponding thiophene-sulfones allows an almost complete fluorescence emission coverage of the visible region of the opticals pectrum (400-700 nm).

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