Ultra-narrowband organic room-temperature phosphorescence achieved by boosting low-frequency vibronic coupling.

September 26, 2026| Source: Proceedings of the National Academy of Sciences of the United States of America

We pioneered a strategy based on low-frequency vibronic coupling to design narrowband room-temperature phosphorescent (RTP) materials. Here we select coronene derivative (CoDe) system and report that attaching aroyl group to the coronene core disrupts its intrinsic symmetry and introduces abundant low-frequency vibrational modes, thereby affording efficient room-temperature phosphorescence with a full width at half maximum (FWHM) of approximately 25 nm or narrower. In CoDe systems functionalized with additional thioether groups, ultra-narrowband organic phosphorescence materials with exceptionally small FWHM (9.6 nm), high afterglow efficiency (50%), and long phosphorescence lifetimes (1.5 s) are achieved in host matrices under ambient conditions. Mechanistic studies reveal that this spectral narrowing relates to the selective amplification of low-frequency vibronic coupling through a moderate heavy-atom effect provided by the thioether groups. Equally crucial would be the suppression of excited-state relaxation and spectral broadening via relatively strong noncovalent interactions between the thioether groups and the host matrices (sulfur bonding interactions) at room temperature.

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Extensive glacier loss in the coterminous United States.

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Physical/TechOctober 20, 2026

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Physical/TechOctober 20, 2026

GTP orchestrates CTP synthase via an allosteric effector-cycling mechanism.

Cytidine triphosphate (CTP), a fundamental building block of RNA, plays vital roles in diverse biological processes. CTP synthase (CTPS) is the only known enzyme for de novo synthesis of CTP. Efficient CTPS catalysis requires guanosine triphosphate (GTP) in a dose-dependent, nonconsumptive manner; however, the precise mechanism by which GTP drives CTP formation remains unclear. Here, we integrate a series of cryo-EM structures of Drosophila melanogaster CTPS captured from actively catalyzing sam

Physical/TechOctober 20, 2026

Antiferromagnetism and tightly bound Cooper pairs induced by kinetic frustration.

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Physical/TechOctober 20, 2026

Coordinated transformations of the labyrinth and occiput during the dinosaur-bird transition.

Evolutionary shape changes of the vertebrate semicircular canals (SCCs) are often ascribed to evolutionary transitions in locomotion, including the origin of flight during the dinosaur-bird transition. However, the potential for transformations of braincase architecture to influence SCC shape independent of sensory-functional adaptation has generally been overlooked. We evaluate the influence of both factors using a large dataset of 146 living and recently extinct crown birds, including taxa rep