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The realization of persistent luminescence and in particular circularly polarized luminescence (CPL) of organic radicals remains a challenge due to their sensitivity to oxygen at ambient conditions and elusive excited state chirality control. Here, it is reported that UV‐irradiation on a supramolecular gel from a chiral triarylamine derivative, TPA‐Ala, led to the formation of luminescent radicals with bright CPL. TPA‐Ala can form an organogel in chloroform with blue emission and supramolecular chirality as demonstrated by both CD and CPL signals. Upon UV 365 nm irradiation, an emission color change from blue to cyan is observed due to the formation of photo‐induced radicals. Interestingly, it is found that the supramolecular gel radicals showed stable luminescence with a lifetime ≈ 10 days in dark environments and inverted CPL, which represents a scarce example with persistent CPL from doublet‐state due to oxygen isolation ability of the gel network. Furthermore, doping a guest dye, Rhodamine B (RhB), into the supramolecular gel (RhB/TPA‐Ala = 30% in molar ratio) successfully obtained a transient white‐light CPL through the superposition of photo‐induced radical and guest dye emissions. This work provides a useful methodology for the fabrication of radical‐based CPL materials via a supramolecular assembly approach. [ABSTRACT FROM AUTHOR]

The photophysical and chiroptical properties of a chiral biquinoline amphiphile were found to be closely related to its aggregate states. Photochromism through photo-induced radical and circularly polarized luminescence were realized in its gel state and thin film state, respectively. [ABSTRACT FROM AUTHOR]

By constructing a supramolecular light‐harvesting chiral nanotube in the aqueous phase, we demonstrate a cooperative energy and chirality transfer. It was found that a cyanostilbene‐appended glutamate compound (CG) self‐assembled into helical nanotubes exhibiting both supramolecular chirality and circularly polarized luminescence (CPL). When two achiral acceptors, ThT and AO, with different energy bands were co‐assembled with the nanotube, the CG nanotube could transfer its chirality to both of the acceptors. The excitation energy could be transferred to ThT but only be sequentially transferred to AO. During this process, the CPL ascribed to the acceptor could be sequentially amplified. This work provides a new insight into the understanding the cooperative chirality and energy transfer in a chiral supramolecular system, which is similar to the natural light‐harvesting antennas. [ABSTRACT FROM AUTHOR]

Multiple noncovalent interactions can drive self-assembly through different pathways. Here, by coordination-assisted changes in π-stacking modes between chromophores in pyrene-conjugated histidine (PyHis), a self-assembly system with reversible and inversed switching of supramolecular chirality, as well as circularly polarized luminescence (CPL) is described. It was found that l-PyHis self-assembled into nanofibers showing P-chirality and right-handed CPL. Upon Zn II coordination, the nanofibers changed into nanospheres with M-chirality, as well as left-handed CPL. The process is reversible and the M-chirality can change to P-chirality by removing the Zn II ions. Experimental and theoretical models unequivocally revealed that the cooperation of metal coordination and π-stacking modes are responsible the reversible switching of supramolecular chirality. This work not only provides insight into how multiple noncovalent interactions regulate self-assembly pathways., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)