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Light has profoundly impacted modern medicine and healthcare, with numerous luminescent agents and imaging techniques currently being used to assess health and treat diseases. As an emerging concept in luminescence, aggregation-induced emission (AIE) has shown great potential in biological applications due to its advantages in terms of brightness, biocompatibility, photostability, and positive correlation with concentration. This review provides a comprehensive summary of AIE luminogens applied in imaging of biological structure and dynamic physiological processes, disease diagnosis and treatment, and detection and monitoring of specific analytes, followed by representative works. Discussions on critical issues and perspectives on future directions are also included. This review aims to stimulate the interest of researchers from different fields, including chemistry, biology, materials science, medicine, etc., thus promoting the development of AIE in the fields of life and health.

In Japan, research activities by junior and senior high school students show an upward trend. However, there are limited examples of research activities in the field of elementary particles and atoms. This is due to the difficulty associated with procuring research tools such as accelerators or particle detectors. Therefore, we hosted the 'Accel Kitchen' in 2018 and 2019 at the Cyclotron and Radioisotope Center (CYRIC) in Tohoku University where junior and senior high school students could participate in ongoing research of particle and atomic physics. At each workshop, 12 junior and senior high school students participated in the beam experiment, including the production of francium atoms (Fr) by the fusion reaction of oxygen and gold, optimizing the transport of the ion beam and identifying the alpha decay nuclei, and laser trapping of Fr for two days. Each group that was involved in the experiment was supported by researchers and university students who acted as mentors. This was the first opportunity for junior and senior high school students to know about the particle beam experiment in Japan.

We publish three Roadmaps on photonic, electronic and atomic collision physics in order to celebrate the 60th anniversary of the ICPEAC conference. In Roadmap I, we focus on the light-matter interaction. In this area, studies of ultrafast electronic and molecular dynamics have been rapidly growing, with the advent of new light sources such as attosecond lasers and x-ray free electron lasers. In parallel, experiments with established synchrotron radiation sources and femtosecond lasers using cutting-edge detection schemes are revealing new scientific insights that have never been exploited. Relevant theories are also being rapidly developed. Target samples for photon-impact experiments are expanding from atoms and small molecules to complex systems such as biomolecules, fullerene, clusters and solids. This Roadmap aims to look back along the road, explaining the development of these fields, and look forward, collecting contributions from twenty leading groups from the field.

Luminescent complexes with arsane ligands have garnered considerable interest due to their uncomplicated structure and effective luminescence. Particularly, rigid monodentate arsane ligands, wherein the substituents of the arsenic atom are bridged, have proven advantageous in enhancing emission intensity. In this study, we synthesized non‐bridged, O‐bridged, S‐bridged, and O,O‐bridged triphenylarsine derivatives using the safe and efficient protocols developed in our previous work. We then created platinum dihalide (PtX2, X=Cl, Br, I) complexes with these arsane ligands. Their structures were determined through single‐crystal X‐ray diffraction, revealing significant influences on geometry by the counter anion and the arsane/phosphane ligand. Additionally, we elucidated the correlation between the ligand structure and the solid‐state emission properties [ABSTRACT FROM AUTHOR]

Heavy atoms can form highly coordinated states, and their optical properties have attracted much attention. Recently, we have demonstrated that a reversible coordination-number shift of hypervalent tin(IV) from five to six can provide predictable hypsochromic shifts in light absorption and emission properties in small molecules and a π-conjugated polymer film. Herein, we show the preparation of seven-coordinated tin and reveal that the binding constant of the seven coordination with ethylenediamine (EDA, K = 2900 M−1) is 200 times higher than that of six coordination with propylamine (PA, K = 14 M−1) owing to the chelate effect. Moreover, reversible vapochromism of the π-conjugated polymer film was observed upon exposure (λabs = 598 nm and λPL = 697 nm) and desorption (λabs = 641 nm and λPL = 702 nm) of EDA vapor. Furthermore, as a unique demonstration, the thermochromic film was prepared by fixing the seven coordination as the initial state using 1,10-phenanthroline. These optical variations are predictable by quantum chemical calculations. Our findings are valuable for the development of designable and controllable stimuli-responsive materials focusing on the inherent properties of the elements. [ABSTRACT FROM AUTHOR]

o-Carborane is an icosahedral cluster containing boron and has been paid attention as a versatile platform for constructing stimuli-responsive materials with solid-state luminescence properties by suppressing aggregation-caused quenching (ACQ), which is the emission annihilation process observed in condensed states, such as concentrated solutions, solids and films. Non-specific intermolecular interactions in the condensed states resulting in ACQ are disturbed by the spherical boron cluster. More recently, it has been demonstrated from several reports that o-carborane is capable of assisting solid-state excimer emission in aryl-modified o-carboranes. Moreover, some of these materials provide unique stimuli-responsiveness. In the commodity design for solid-state luminescent materials, o-carboranes are responsible for disturbing intermolecular interactions and subsequently presenting solid-state luminescence. On the other hand, excimer emission, which is inducible from the intermolecular photophysical process, has been discovered in the solid state based on o-carborane materials. In this manuscript, recent progress in stimuli-responsive luminescent materials via excimer formation will be described. Moreover, as the further potential of o-carborane materials, recent findings on the photo-salient effect which can be induced through excimer formation followed by photoreaction will also be explained. [ABSTRACT FROM AUTHOR]

In this work, bisarsine oxides were evaluated as novel bridging ligands, aiming to develop practical and efficient luminescent lanthanide coordination polymers. We have synthesized one‐dimensional (1D) Eu3+ coordination polymers that incorporate bisarsine oxide bridging ligands and hexafluoroacetylacetonate anions. These polymers exhibited a denser packing of chains compared to analogous polymers bridged with bisphosphine oxides. The coordination polymers demonstrated exceptional thermal stability and substantial emission quantum yields. Additionally, the bisarsine oxides induced a pronounced polarization effect, facilitating a sensitive electric dipole transition that yields considerably narrow band red emission. Remarkably, the Eu3+ coordination polymers with bisarsine oxides maintained intense emission even at 550 K. A distinctive feature of these polymers is their heating‐induced emission enhancement observed when the temperature was increased from 300 K to 400 K. [ABSTRACT FROM AUTHOR]

Cylinder‐shaped macrocycles composed of π‐panels have attracted special attention as one of the best platforms for the development of organic molecule‐based chiroptical materials. Pillar[n]arenes are a class of macrocycles with the advantage of easy preparation but have not been extensively investigated from the perspective of luminescent molecules. However, common alkoxy pillar[n]arenes are fluorescent in non‐haloalkane solvents, showing potential to be used for molecule‐based chiroptical materials. In this work, circularly polarized luminescence (CPL) spectra are reported for a pillar[5]arene with stable planar chirality using tetrahydrofuran (THF) and cyclohexane as solvents, which has been missing for many years. The pillar[5]arene also forms co‐aggregates with 1,4‐bis(phenylethynyl)benzene and 1,4‐bis[(pentafluorophenyl)ethynyl]benzene in THF/H2O mixtures, owing to a hydrophobic effect. The co‐aggregates with the fluorinated π‐rod display a new low‐energy absorption peak and broad emission band as well as intense circular dichroism and CPL signals. Chiral information from the enantiopure pillar[5]arene core is efficiently transmitted to the co‐aggregates with the π‐conjugated rod, leading to the highest dissymmetry factor for CPL (2.9 × 10−2 at 472 nm) among pillar[n]arene‐based CPL materials. [ABSTRACT FROM AUTHOR]

Luminescence in the second near‐infrared (NIR‐II, 1,000–1,700 nm) window is beneficial especially for deep tissue imaging and optical sensors because of intrinsic high permeability through various media. Strong electron‐acceptors with low‐lying lowest unoccupied molecular orbital (LUMO) energy levels are a crucial unit for donor–acceptor (D–A) π‐conjugated polymers (CPs) with the NIR‐II emission property, however, limited kinds of molecular skeletons are still available. Herein, D–A CPs involving fluorinated boron‐fused azobenzene complexes (BAz) with enhanced electron‐accepting properties are reported. Combination of fluorination at the azobenzene ligand and trifluoromethylation at the boron can effectively lower the LUMO energy level down to −4.42 eV, which is much lower than those of conventional strong electron‐acceptors. The synthesized series of CPs showed excellent absorption/fluorescence property in solution over a wide NIR range including NIR‐II. Furthermore, owing to the inherent solid‐state emissive property of the BAz skeleton, obvious NIR‐II fluorescence from the film (up to λFL=1213 nm) and the nanoparticle in water (λFL=1036 nm, brightness=up to 29 cm−1 M−1) were observed, proposing that our materials are applicable for developing next‐generation of NIR‐II luminescent materials. [ABSTRACT FROM AUTHOR]

A novel C–N axially chiral molecule composed of two tert-butyl-substituted benzo[b]phenoxazine (BPO) was synthesized via solvent-free reactions. The absolute configurations of the enantiomers were determined by X-ray single-crystal analysis. The enantiomers had a sufficiently high racemization barrier to ignore racemization at room temperature (149 ± 20 kJ mol−1), and the solutions exhibited dual circularly polarized emissions stemming from fluorescence and phosphorescence of ‖gCPL‖ = ca. 1 × 10−3. [ABSTRACT FROM AUTHOR]

A benzannulated double aza[9]helicene 1 was successfully synthesized via a one‐pot oxidative fusion reaction. 1 was derivatized to N‐alkylated double aza[9]helicene 1‐Et and 1‐Bu, whose structures were determined by X‐ray diffraction analysis. 1‐Et and 1‐Bu exhibited red‐shifted absorption and fluorescence spectra compared to single aza[9]helicene. The double aza[9]helicenes were expected to have two different conformers. Consistent with solid‐state structure, the chiral‐isomer was estimated to be more stable by 16 kcal/mol relative to meso‐isomer. Indeed, enantiomers of 1‐Et and 1‐Bu were optically resolved by HPLC and showed mirror‐imaged CD and CPL spectra with the CPL brightness up to 19.2 M−1cm−1 for 1‐Bu. [ABSTRACT FROM AUTHOR]