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Boosting the circularly polarized luminescence of small organic molecules has been a stubborn challenge because of weak structure rigidity and dynamic molecular motions. To investigate and eliminate these factors, here, we carried out the structure‐property relationship studies on a newly‐developed axial chiral scaffold of bidibenzo[b,d]furan. The molecular rigidity was finely tuned by gradually reducing the alkyl‐chain length. The environmental factors were considered in solution, crystal, and polymer matrix at different temperatures. As a result, a significant amplification of the dissymmetry factor glum from 10−4 to 10−1 was achieved, corresponding to the situation from (R)‐4C in solution to (R)‐1C in polymer film at room temperature. A synergistic strategy of increasing the intramolecular rigidity and enhancing the intermolecular interaction to restrict the molecular motions was thus proposed to improve circularly polarized luminescence. The though‐out demonstrated relationship will be of great importance for the development of high‐performance small organic chiroptical systems in the future. [ABSTRACT FROM AUTHOR]

Chiral luminescent materials are a class of materials capable of emitting circularly polarized light (CPL). Radicals are unique open‐shell compounds with exceptional photoelectromagnetic properties that can be exploited in constructing novel chiral luminescent materials. This Concept discussed three main catalogues for producing organic CPL radicals, intrinsic chiral luminescent radicals, luminescent radicals with chiral substitutions, and field‐regulation‐induced chiral luminescent radicals. The brief review of their properties aims at providing basic guidelines and supporting further development of novel chiral luminescent radical systems. [ABSTRACT FROM AUTHOR]

The development of ultra‐long room‐temperature phosphorescence (UL‐RTP) in processable amorphous organic materials is highly desirable for applications in flexible displays, anti‐counterfeiting, and bio‐imaging. However, achieving efficient UL‐RTP from amorphous materials remains a challenging task, especially with activation by visible light and a bright afterglow. Here we report a general and rational molecular‐design strategy to enable efficient visible‐light‐excited UL‐RTP by multi‐esterification of a rigid large‐plane phosphorescence core. Notably, multi‐esterification minimizes the aggregation‐induced quenching and accomplishes a ′four birds with one stone′ possibility in the generation and radiation process of UL‐RTP: i) shifting the excitation from ultraviolet light to blue‐light through enhancing the transition dipole moment of low‐lying singlet‐states, ii) facilitating the intersystem crossing process through the incorporation of lone‐pair electrons, iii) boosting the decay process of long‐lived triplet excitons resulting from a significantly increased transition dipole moment, and iv) reducing the intrinsic triplet nonradiative decay by substitution of high‐frequency vibrating hydrogen atoms. All these factors synergistically contribute to the most efficient and stable visible‐light‐stimulated UL‐RTP (lifetime up to 2.01 s and efficiency up to 35.4 % upon excitation at 450 nm) in flexible films using multi‐esterified coronene, which allows high‐tech applications in single‐component time‐delayed white light‐emitting diodes and information technology based on flashlight‐activated afterglow encryption. [ABSTRACT FROM AUTHOR]

This article provides a comprehensive overview of circularly polarized room-temperature phosphorescence (CP-RTP) in purely organic luminophores. It explores the challenges in constructing purely organic CP-RTP systems and discusses the photophysics of CP-RTP. The article also examines different types of purely organic CP-RTP systems based on chiral structures and offers insights and suggestions for future advancements in this area. Overall, ongoing research in this field shows promise for the development of purely organic CP-RTP systems with various applications. [Extracted from the article]

Novel accessible scaffold featuring circularly‐polarized room‐temperature phosphorescence (RTP) is attractive but challenging. Herein, we report a new feasibly separable bidibenzo[b,d]furan compound with strong circularly‐polarized RTP when doping into the rigid polymer matrix. The simple silica‐gel column can separate the absolute chiral R‐isomer with excellent chiroptical properties. The experimental data reveal that the treated films exhibit an RTP efficiency of 14.8 %, a largest dissymmetric factor of 0.12, and a longest lifetime of 0.56 s under ambient conditions. It is found that reducing the nonradiative decays boosts the intrinsic circularly‐polarized RTP emission. The impressive results indicate that the locked axial chirality skeleton endows the potential of achieving superior circularly‐polarized emission for the small organic optoelectronic molecules. [ABSTRACT FROM AUTHOR]

Phototheranostic agents have thrived as promising tools for cancer theranostics because of the integration of sensitive in situ fluorescence imaging and effective multi‐model synergistic therapy. However, how to manipulate the intangible photon energy transfer to balance the competitive radiative and nonradiative processes is still challenging. Although numerous phototheranostic molecules are reported, their complicated molecular design and tedious synthesis often stumble further their development. Herein, three simple molecules with electron donating−accepting structures are developed. The electron acceptor engineering on molecules by introducing acridinium unit gives rise to TPEDCAc with aggregation‐induced second near‐infrared emission (AIE NIR‐II), high reactive oxygen species generation capability, and excellent photothermal conversion efficiency (44.8%) due to the drastic intramolecular motion of large acridinium rotor and balanced AIE effect. Experimental analysis and calculation on the controlled molecules suggested that large torsional angle and the strong electron‐withdrawing ability of the acridinium unit are keys for NIR‐II emission and balanced photodynamic/photothermal conversion. Impressively, the positively charged TPEDCAc shows mitochondria‐targeting capability and high performance in in vivo multi‐modal cancer theranostics under NIR laser irradiation. Hence, this work not only provides a single NIR‐II AIE‐based multi‐modal cancer theranostic system but inspires new insights into future development of new theranostic platforms. [ABSTRACT FROM AUTHOR]

Research on molecularly imprinted polymers (MIPs) has long been receiving much attention, but issues concerning the recognition mechanism and how the impact factors work are still far from clear. In this work, we studied the imprinting and recognition procedures from a new perspective. Two factors that have a major impact on the imprinting performance were studied separately: one is the functional groups (FGs) of the template and the other is the size of the template. A series of aggregation-induced emission molecules (AIEgens) was employed as the templates, and they were selected elaborately, one group of which having different functional groups with a similar size, while the other being different in molecular size. It was found that the MIP was inclined to combine with molecules with more effective functional groups or with smaller sizes. Meanwhile, the more ordered sites and the larger cavities in the polymers afforded the MIP with better adsorption performance. The binding energy (ΔE) and the mechanism at the molecular level between templates and polymers were analyzed by using density functional theory (DFT) calculations, and the results were consistent with experimental results in the aspect of the FG effect. In addition, the unique luminescence properties of AIEgens allow for visible observation of the change of the template within the polymer during preparation and rebinding processes. More importantly, quantification of template molecules during the adsorption process was fulfilled based on their solid-state fluorescence intensities, which opens a new door for AIEgen application. A comparison with the common method of UV-vis spectrometry revealed that solid-state fluorescence measurement has the advantages of direct detection, easy operation, a wide linear range and so on. [ABSTRACT FROM AUTHOR]

A pentagonal macrocycle (MC5-PER) with radialene topology was facilely synthesized through a selective one-pot Suzuki–Miyaura cross-coupling reaction. The resulting product is endowed with a pentagonal architecture as revealed by its single crystal structure, which affords the smallest ring strain and the best conjugation. As tetraphenylethene subunits are embedded, MC5-PER is highly emissive in the solid state due to the aggregation-induced emission effect. Because of the flexible structure and preferable fibre-like self-assembly, the aggregate of MC5-PER displays interesting polymorphism-dependent emission and acts as a sensitive fluorescence sensor for explosives detection. [ABSTRACT FROM AUTHOR]

Herein the novel tetraphenylethylene (TPE) derivative 1 was designed with an integration of aggregation‐induced emission (AIE), multi‐state mechanochromism and self‐recovery photochromism. The molecule was susceptible to grinding, heating and vapor fuming and showed corresponding transition of its emission colors. The heated powder or single crystal of 1 exhibited reversible photochromism. After a short period of UV irradiation, it showed a bright red color, but recovered to its original white appearance within 1 min. The photochromism is due to the formation of photocyclization intermediates upon UV irradiation, while the eversible mechanochromism is attributed to the weak molecular interactions derived from head‐to‐tail stacking of the molecules. This reversible multi‐state, high‐contrasted and rapid responsive mechanochromic and photochromic property cooperatively provide double enhancement of a multimode guarantee in advanced anti‐counterfeiting. [ABSTRACT FROM AUTHOR]

Abstract: Pure organic materials with ultralong room‐temperature phosphorescence (RTP) are attractive alternatives to inorganic phosphors. However, they generally show inefficient intersystem crossing (ISC) owing to weak spin–orbit coupling (SOC). A design principle based on the realization of small energy gap between the lowest singlet and triplet states (ΔEST) and pure ππ* configuration of the lowest triplet state (T1) via structural isomerism was used to obtain efficient and ultralong RTP materials. The meta isomer of carbazole‐substituted methyl benzoate exhibits an ultralong lifetime of 795.0 ms with a quantum yield of 2.1 %. Study of the structure–property relationship shows that the varied steric and conjugation effects imposed by ester substituent at different positions are responsible for the small ΔEST and pure ππ* configuration of T1. [ABSTRACT FROM AUTHOR]

Based on an analogue of green fluorescent protein chromophore benzylidene-methyloxazolone (BMO), a series of fluorophores with an additional phenyl group, BMO-PH, BMO-PF, BMO-PM and BMO-PC, have been prepared and are found to be AIE-active. Their solutions are weakly emissive and their aggregation or solid states are highly emissive. Although these compounds readily undergo efficient E/Z isomerization (EZI) upon UV irradiation in solution, the intramolecular rotation around the double bond and phenyl rotation around the single bond serve as the key non-radiative decay channels to dissipate the excited-state energies. The EZI is only the phenomenal result. In aggregates, these intramolecular motions are greatly restricted by multiple intermolecular interactions, resulting in the AIE effect. To ensure a high solid-state quantum yield, prevention of detrimental π–π stacking is of essence. An additional phenyl group to BMO is found to increase the π–π distance and weaken the π–π interaction. Thus, the quantum yields are increased. Strong electron-donating groups and extended conjugation are effective at tuning the emission color bathochromically. Based on these principles, we succeeded in increasing the solid-state quantum yield up to 50% and obtaining a red emission maximum of 635 nm. Moreover, these compounds are promising for applications in photoswitches and fluorescent patterns, and their crystals are good candidates for luminescent waveguides with low light loss efficiency. [ABSTRACT FROM AUTHOR]

Herein, two novel N-phenylated N-heteroacenes ( 1 and 2) are reported, along with details of their synthesis, structures, and properties. Compound 1 is a N-hetero analogue of rubrene, but differs from rubrene by having a bent backbone and behaving as an insulator in the solid state owing to the lack of π-π interactions. Compound 2 is a N-hetero analogue of 6,13-diphenylpentacene (DPP) with essentially the same molecular geometry and crystal packing as DPP, but exhibiting a field effect mobility higher than that of DPP by two orders of magnitude. [ABSTRACT FROM AUTHOR]

Construction of a donor–acceptor (D–A) structure and extension of π-conjugation are the commonly used strategies to shift the emission of luminophores to the red region. However, molecules with high conjugation and a strong D–A effect tend to show weak emission due to the severe π–π interactions and twisted intramolecular charge transfer (TICT) effects. The turn-on characteristic of AIE luminogens (AIEgens) will also be lost due to the conjugation-enhanced emission in the solution state. Herein, a polyyne-bridged AIE luminogen (2TPE-4E) with long wavelength absorption and red emission has been afforded. Despite its large π-conjugation, 2TPE-4E suffers from no emission quenching resulted from strong π–π interactions and twisted intramolecular charge transfer effects. The strong red emission and the high photostability of 2TPE-4E inspired us to use it for targeted-imaging of cancer cells and monitoring the receptor mediated endocytosis process. [ABSTRACT FROM AUTHOR]

We present a nitrogen-containing polycyclic aromatic hydrocarbon (N-PAH), namely 12-methoxy-9-(4-methoxyphenyl)-5,8-diphenyl-4-(pyridin-4-yl)pyreno[1,10,9- h, i, j]isoquinoline ( c-TPE-ON), which exhibits high quantum-yield emission both in solution (blue) and in the solid state (yellow). This molecule was unexpectedly obtained by a three-fold, highly regioselective photocyclodehydrogenation of a tetraphenylethylene-derived AIEgen. Based on manifold approaches involving UV/Vis, photoluminescence, and NMR spectroscopy as well as HRMS, we propose a reasonable mechanism for the formation of the disk-like N-PAH that is supported by density functional theory calculations. In contrast to most PAHs that are commonly used, our system does not suffer from entire fluorescence quenching in the solid state due to the peripheral aromatic rings preventing π-π stacking interactions, as evidenced by single-crystal X-ray analysis. Moreover, its rod-like microcrystals exhibit excellent optical waveguide properties. Hence, c-TPE-ON comprises a N-PAH with unprecedented luminescent properties and as such is a promising candidate for fabricating organic optoelectronic devices. Our design and synthetic strategy might lead to a more general approach to the preparation of solution- and solid-state luminescent PAHs. [ABSTRACT FROM AUTHOR]

Molecules with Möbius topology have drawn increasing attention from scientists in a variety of fields, such as organic chemistry, inorganic chemistry, and material science. However, synthetic difficulties and the lack of functionality impede their fundamental understanding and practical applications. Here, we report the facile synthesis of an aggregation-induced-emission (AIE)-active macrocycle (TPE-ET) and investigate its analogous triply and singly twisted Möbius topologies. Because of the twisted and flexible nature of the tetraphenylethene units, the macrocycle adjusts its conformations so as to accommodate different guest molecules in its crystals. Moreover, theoretical studies including topological and electronic calculations reveal the energetically favorable interconversion process between triply and singly twisted topologies. [ABSTRACT FROM AUTHOR]

The facile synthesis of a tetraphenylethene-based macrocycle having aggregation-induced emission characteristics and that expresses illusory topology of the Penrose stairs is presented. As a result of the twisted chirality ( P or M) of the tetraphenylethene unit and the axial chirality of the macrocyclic linkage ( R or S), the macrocycle exhibits two absolute configurations whose interconversion is energetically favorable as revealed by theoretical calculations. [ABSTRACT FROM AUTHOR]

In their Communication (e202202977), Zikai He et al. report on the circularly polarized room-temperature phosphorescence of a bidibenzo[ I b,d i ]furan scaffold with locked axial chirality. Bidibenzo[b,d]furan, Circularly-Polarized Luminescence, Locked Axial Chirality, Poly(Vinyl Alcohol), Room-Temperature Phosphorescence Keywords: Bidibenzo[b,d]furan; Circularly-Polarized Luminescence; Locked Axial Chirality; Poly(Vinyl Alcohol); Room-Temperature Phosphorescence EN Bidibenzo[b,d]furan Circularly-Polarized Luminescence Locked Axial Chirality Poly(Vinyl Alcohol) Room-Temperature Phosphorescence 1 1 1 07/20/22 20220725 NES 220725 B Organic Electronics b . [Extracted from the article]

Background:Review of recent journal articles and various relevant current textbooks provides strong evidence to show that anticholinergic burden is a material issue in frail and at-risk patients. This study assesses the anticholinergic burden in a group of patients in residential care facilities and then applies a theoretical intervention model. It is based on a scoring system known as the Anticholinergic Cognitive Burden (ACB) scale, and attempts to reduce the anticholinergic burden while maintaining therapeutic benefits.Methods:A database of 691 patients was analyzed for each individual's ACB based on the scale of scoring produced by groups of experts in the area. A theoretical intervention was then conducted using relevant, evidence-based practice guidelines for clinical therapeutics in Australia. The intervention had the aim of reducing the total ACB without affecting the apparent intended effectiveness of the prescribed therapy.Results:Of the 35% (n = 242) patients who score at least 1 point on the ACB, a reduction is achievable in 59% of the cases. In particular, the reduction from a clinically significant score of 3 or above to 2 or below for 49 of those patients is possible in 85% of the cases. Overall, this represents a reduction from 7.10% to 1.01% for the entire population. It is also found that of the 246,960 counts of items dispensed (both prescription and non-prescription) for these patients, 47,334 (or 19.2%) of these were of agents on the ACB scale.Conclusions:The study found that it appears to be possible that the total ACB of a group of 691 patients can be significantly reduced. [ABSTRACT FROM PUBLISHER]

Add an O: A new strategy for preparing solution‐processed organic thin‐film transistors (OTFTs) is based on enhancing the surface energy of self‐assembled monolayers (SAMs) by inserting polar oxygen atoms into the long alkyl chain of phosphonic acids. SAMs of these phosphonic acids on a high‐k metal oxide layer lead to solution‐processed n‐channel OTFTs with average field effect mobilities of up to 2.5 cm2 V−1 s−1 and low operational voltages. [ABSTRACT FROM AUTHOR]

Three new members of N-heteropentacenes explored herein have adjacent pyrazine and dihydropyrazine rings at one end of the pentacene backbone. Interesting findings from this study include self-complementary N–H···N H-bonds in the solid state, solvent-dependent UV–vis absorption caused by H-bonding, and new p-type organic semiconductors with field effect mobility up to 0.7 cm2V–1s–1. [ABSTRACT FROM AUTHOR]

The development of novel luminescent radicals, characterized by their unique doublet emission, endows a significant challenge. In this study, we reported the synthesis of a luminescent neutral radical, BCzAnM‐R, tailored by two carbazolyl groups and an anthryl group to achieve a nonalternant structure. It exhibited near‐infrared emission with a peak at 1020 nm in toluene. Interestingly, its corresponding cation, BCzAnM‐C, was synthesized through an unconventional SnCl2‐mediated reduction‐aromatization‐oxidation reaction in one‐pot and gram‐scale. The cation demonstrated remarkable stability for up to weeks in ambient conditions and facilitated the silica‐gel chromatography isolation as an organic salt with SnCl3− as the counter ion. The carbazolyl groups effectively modulate molecular structures, photophysical properties, and stabilities. Notably, BCzAnM‐R represents the first luminescent triarylmethyl radical with two carbazolyl groups directly attached to the central carbon. [ABSTRACT FROM AUTHOR]

It is challenging to achieve precise control on the properties of organic π‐functional materials to widen their practical applications. On the other hand, the study of aggregation‐induced emission luminogens (AIEgens) helps achieve such goals because of inherent relationships between their luminescence behaviors and conformational variations that allow for the visual monitoring of the changes in the material properties. Inspired by this, in this work, three AIE isomers are fabricated in structures consisting of tetraphenylpyrazine and triphenylethene units with para‐, meta‐, and ortho‐position linkages, respectively. The isomerism effect brings about significantly decreased luminescence efficiency, subtly blueshifted emission, basically reduced AIE effect but boosted porosity in the aggregate state as the conformation of AIEgens evolves from an extended to a folded one. Based on the distinct properties, their respective use in blue organic light‐emitting diodes, nanofluorescent probes, and molecule‐capturing porous crystals are investigated. This work not only achieves precise property control by using the isomerism effect of AIEgens but also provides useful information on the future design of π‐conjugated materials with advanced functionalities. [ABSTRACT FROM AUTHOR]