Rare earth (RE) crystals have garnered considerable attention as second-order nonlinear optical (NLO) materials, owing to highly electropositive nature and large ionic radii of RE cations, which facilitate strong ionic bonding, structural versatility, and enhanced NLO susceptibilities. Despite these intrinsic advantages, achieving simultaneously strong NLO activity and deep-ultraviolet (deep-UV) transparency in RE crystals remains a formidable challenge. Herein, we report the rational design and synthesis of a new family of RE crystals enabled by a ternary anion-engineering strategy, in which pi-conjugated carbonate, non-pi-conjugated sulfate, and lone-pair-electron-containing hydroxyl group are synergistically integrated into a single crystal lattice. The cooperative interplay among these chemically and electronically distinct anions induces a new noncentrosymmetric structural motif, giving rise to exceptional deep-UV transparency, with an absorption edge below 190 nm, surpassing that of many reported RE NLO crystals constructed via complementary anion engineering. Furthermore, such crystals exhibit a strong second-harmonic generation response, with an intensity 2.5 times that of Y-cut quartz at 860 nm, along with a suitable birefringence of 0.023@1064 nm. This work provides a versatile design paradigm for the development of high-performance RE-based deep-UV NLO materials, and underscores the critical role of multi-anions in tuning structural distortion and optical functionality.

Agents to combine functions simultaneously are highly needed but still challenging in synergistic therapy. Particularly, capabilities to deplete glutathione (GSH) in tumors and monitor their process are also important. Therefore, platinum(II) metallacycles are prepared by using aggregation-induced emission active ligands. Despite their similar structures, high emission for Mh1 is obtained (PLQY = 49.2%) in solids, but a PLQY of only 6.8% is recorded for Mh2. NIR emission in Mh2 can be turned-on in depleting GSH by releasing emissive ligands. Also, both type I and type II reactive oxygen species (ROS) are obtained in Mh2 nanoparticles. Due to the depletion of GSH and generation of ROS, oxidative stress in immunogenic cell death can be induced. By combining chemotherapy and photoimmunotherapy, synergistic therapy in vivo is obtained for Mh2-NPs to well inhibit the tumor growth, also showing antitumor immune effects in distant tumors. The work here provides some guidelines in designing the multi-functional agents, showing the great potentials in efficient cancer therapy.

Isopropenyl 4-[bis(4-methylphenyl)amino]phenyl ketone (IMAPK) (1-[4-(di- p -tolylamino)phenyl)-2-methylprop-2-en-1-one], a vinyl ketone monomer bearing a triphenylamine moiety in the side chain, was copolymerized with methyl methacrylate (MMA) by a free radical method. While the vinyl ketone is known to show rather low reactivity in radical polymerization, the copolymerization reactions afforded polymers at higher monomer conversions. Photophysical and electrochemical properties of the copolymers were compared with those of t -butyl 4-[bis(4-methylphenyl)amino]phenyl ketone (BMAPK) (1-[bis(4-methylphenyl)amino]phenyl-2,2-dimethylpropan-1-one) as a model compound of IMAPK unit. The polymers and the model compound exhibit distinctive absorption and emission properties and oxidation potentials. Especially, the copolymer with a unit ratio of [IMAPK]/[MMA] = 1/7 showed as high as about 1.5 times higher emission efficiency than BMAPK.

Coordination-driven self-assembly offers a powerful toolkit for constructing sophisticated functional architectures. Rigid ligands are widely employed as building blocks in metallo-supramolecular chemistry due to their structural predictability during self-assembly. In contrast, flexible building blocks─though capable of offering greater structural diversity and stimuli-responsiveness─are rarely used, as their conformational freedom often complicates structural control. Consequently, the integration of flexible ligands into metallo-supramolecular systems remains underexplored. To address this challenge, we employ a postassembly ligand-exchange approach to construct a series of heteroleptic metallo-supramolecular cuboctahedra incorporating both rigid and flexible ligands. Investigations of chain length dependence reveal that flexible alkyl-diamine incorporation affects cage hydrodynamic size and stability, with optimal stability achieved at 8 units. This combined bottom-up and top-down synthetic approach offers a promising strategy for engineering complex architectures from flexible building blocks for further exploration of chemistry within a confined space.

Precise control over the presence and position of knots in polymers remains a long-standing synthetic challenge, with theory indicating broad implications for properties and function. Here we report on a topological synthon approach-extension and macrocyclization of an overhand knot-that enables the high yielding synthesis of closed-loop trefoiled polymers with narrow polydispersity and tunable topological parameters. From the same set of building blocks we prepared linear, cyclic and trefoiled topoisomers of matched chemical composition, allowing topology-property relationships to be examined directly. Low-temperature ultrahigh-vacuum scanning tunnelling microscopy resolved three conformers of trefoiled polystyrene, with high-, medium- and low-symmetry forms whose populations depend on chain length, local flexibility and solvation. Coarse‑grained Langevin dynamics reproduce these distributions and indicate that bending energy and conformational entropy govern conformer stability. Metal binding localizes the knotted region, reminiscent of protein/DNA knot translocation. The synthon also affords trefoiled poly(ethylene glycol) and trefoiled polystyrene-poly(ethylene glycol) diblock copolymers, demonstrating the generality of the approach across polymer backbones.

Inspired by the binary necklace problem in combinatorial mathematics, we designed and constructed a series of metallo-supramolecular polygons via coordination-driven self-assembly (CDSA) of an anisotropic tetratopic terpyridine ligand with Zn(II) ions. Such anisotropic units with two different orientations serve as two types of “beads” in the assembly process, resulting in supramolecular “necklaces” that, in theory, exhibit numerous isomers. Through combinatorial analysis, molecular modelling, and experimental validation, we identified three predominant hexameric isomers with distinct symmetrical characteristics. The experimental distribution of these isomers agreed well with their formation probabilities resolved from the binary necklace problem. Notably, detailed structural analysis by scanning tunneling microscopy imaging confirmed the pivotal role of entropy in determining the isomeric distribution. Upon heating under diluted conditions, such three hexameric isomers were transformed into a single pentameric structure as the dominant species, which aligns with the theoretical predictions of binary necklace problem and minimized strain energy. This transformation was corroborated with theoretical modelling and experimental study, highlighting the critical influence of symmetry and entropy in directing the thermodynamic pathway of CDSA. This work provides a notable example of mathematically rationalized supramolecular chemistry, offering profound insights into the thermodynamic aspects of CDSA.

Mechanically interlocked polymers (MIPs) offer unconventional architectures that expand the design space of polymer chemistry, making them an emerging focus of polymer and supramolecular science. Yet their synthesis still lacks the precision and control established in conventional polymer chemistry. We report a living ring-opening polymerization that enables controlled construction of topologically diverse polyrotaxanes from two monomers─[2]catenanes and c[1]daisy chains. The method delivers main-chain and daisy-chain architectures with predictable molecular weights, narrow dispersities (Đ ≤ 1.19), and block copolymer access. Comparative studies reveal topology-dependent reactivity, underscoring the role of conformational constraints in polymerization kinetics. This unified route establishes a versatile platform for programmable MIP synthesis, bridging molecular topology with materials design and paving the way for next-generation mechanically bonded polymers.

ABSTRACT Metallosupramolecular assembly traditionally employs rigid ligands to ensure structural predictability, yet flexible ligands‐based assembly remains a formidable challenge due to their conformational indeterminacy. In this study, we report a unique supramolecular trimer assembled from a flexible tripodal ligand, where each arm features a bis(urea) anion‐binding site and a terminal pyridine metal‐binding site. Upon coordination with sulfate and Pd 2+ or Pt 2+ , sulfate–bis(urea) hydrogen‐bonding directs the spatial arrangement of pyridine units. Single‐crystal x‐ray diffraction reveals racemic mixtures of supramolecular trimers with clockwise ( M ) or counterclockwise ( P ) helicity, composed of three stacked figure‐eight subunits and resembling the morphology of a Calochortus venustus tulip. Such assembly is co‐stabilized by metal–pyridine coordination (first‐sphere coordination), N–H···O/C–H···O H‐bonding with sulfates (second‐sphere coordination), and sulfate–Pd 2+ electrostatic attraction. The trimer remains stable in solution, as confirmed by NMR, DOSY, and ESI‐MS experiments. Concentration‐dependent NMR studies elucidate a multistep assembly pathway from a 1:1 sulfate complex, through a figure‐eight subunit, to the final architecture. Moreover, replacing the non‐coordinating pyridine unit with a chiral group successfully induces enantiopure trimers. This work establishes a paradigm of anion‐dictated assembly through cooperative first‐ and second‐sphere coordination, offering a new avenue for supramolecular assemblies.

Syntheses of low-dimensional macromolecules with increasing size and complexity in solution pose substantial challenges in terms of their precise structural characterization. Electrospray ionization coupled with scanning tunneling microscopy (ESI-STM) has emerged as a promising tool for the characterization of these nonsublimable macromolecules in real space. However, the weak ionization of such macromolecules and the three-dimensional configuration of the attached solubilizing groups severely impede high-resolution STM imaging. In this work, we synthesized a series of graphyne-graphdiyne concentric macrocycles with triphenylamine groups to enhance the ionization efficiency, which in turn ensures the sample cleanliness for STM characterization. To tackle imaging interference from solubilizing groups, single-molecule tip manipulation and large-scale bromine-assisted thermal treatment were developed for alkoxy and/or alkyl chain removal, enabling the acquisition of unprecedented bond-resolving structural images and angstrom-resolution frontier molecular orbital maps. Our methods resolve the long-standing dilemma between the solubility requirements of solution synthesis and the molecular planarization demands of high-resolution STM characterization, pushing the resolution limit of macromolecules to the angstrom level.

The development of high-performance deep-ultraviolet (deep-UV) second-order nonlinear optical (NLO) crystals that simultaneously combine noncentrosymmetric crystal structure, broad transparency, strong second-harmonic generation (SHG) activity, and high thermal and chemical stability remains a formidable challenge due to intrinsic trade-offs among these properties. Herein, we present a multicomponent structural design strategy that enables the rational synthesis of a new KBe2BO3F2 (KBBF)-like rubidium lanthanum sulfate, RbLa(SO4)2. In this crystal, the highly polarizable [LaO10] unit substitutes for [BeO3F] to enhance polarization, the non-π-conjugated [SO4] group replaces [BO3] to maximize the SHG response, and the alkali metal Rb+ cation improves optical transparency and structural robustness. Consequently, RbLa(SO4)2 exhibits excellent deep-UV transparency, featuring an absorption cutoff below 190 nm, along with pronounced SHG responses about 120 times that of Y-cut quartz at 880 nm and 1.5 times stronger than that of KH2PO4 at 1064 nm. Moreover, the crystal shows exceptional thermal stability, maintaining structural integrity up to 1000 °C, making it among the most thermally robust NLO sulfates reported to date. Experimental and theoretical analyses reveal that the synergistic alignment of polarizable [LaO10] polyhedra and [SO4] tetrahedra underpins their high NLO performance. This study provides a promising design paradigm for rare earth sulfate-based deep-UV NLO crystals.

Regulating multistimulus responses in artificial systems remains a challenge in smart material development. We present a versatile chemical switching system that precisely controls the self-assembly of metal-organic cages via temperature and solvent changes. The key component, cyclo[2](1,3-(4,6-dimethyl)benzene) (4-pyridine)[6](1,3-(4,6-dimethyl)benzene) (CP2), was generated as three atropisomers (1, 2, and 3) with Cs, C1, and C2v symmetries. Thermally, metastable isomers (1 and 2) convert into the stable isomer (3), which reacts with Pd2+ to form specific molecular cages. Depending on the solvent, either rectangular M2L2 cages (5' and 5) form in 1,4-dioxane or hexagonal M3L3 cages (6) in 1,1',2,2'-tetrachloroethane. The solvent dictates the cage type and enables reversible transformation between cages 5 and 6. Additionally, cage 5', formed from metastable isomer 1, can switch to other cage types (i.e., 5 or 6) depending on temperature and solvent conditions. This multipathway system offers a precise strategy for controlling self-assembly in smart materials.

BACKGROUND:Soft ionization mass spectrometry is an excellent direct detection technique with advantages such as speed, simplicity, and ease of operation. Chemical ionization (CI) is a typical soft ionization method that enables targeted detection of specific compounds through reactions between reagent ions and analytes. However, current CI methods, such as proton transfer reaction mass spectrometry (PTR-MS) and selected ion flow tube mass spectrometry (SIFT-MS), cannot achieve high sensitivity and low fragmentation for n-alkanes. Therefore, there is a need for a detection method tailored for n-alkanes that provides high sensitivity and minimizes fragmentation to preserve the sample's integrity. RESULTS:In this work, a novel photoionization-induced nitrogen dioxide cation chemical ionization time-of-flight mass spectrometry (PNO2CI-TOFMS) was developed by adopting photoionization-generated NO2+ as the reactant ion. A low-fragmentation hydride transfer reaction ionization process between the NO2+ ion and n-alkane molecule was identified and investigated, resulting in easily identifiable [M - H]+. The concentration of NO2 reagent gas, the electric field intensity in the ionization region, and the ion source pressure were systematically examined. Consequently, the limits of detection (LODs) ranging from 0.18 to 2.37 ppbv (parts per billion by volume) were achieved for C5-C11 n-alkanes within just 5 s. Furthermore, the degree of fragmentation was remarkably low, with the branching ratio of the dehydrogenated molecular ion peaks varying between 90.9 % and 99.9 %. The application of PNO2CI-TOFMS on the detection of n-alkanes in gas samples collected from a petroleum refinery demonstrated the satisfactory performance and potential of this system for n-alkanes in atmospheric measurement. SIGNIFICANCE:The development of the PNO2CI-TOFMS method offers a new option for detecting n-alkanes, providing fast detection, high sensitivity, and lower fragmentation. For C5-C11 n-alkanes, the branching ratio can be controlled above 90 %, with detection results obtained in just 5 s. It has already demonstrated its potential in real air samples, and in the future, it will offer more possibilities for n-alkane detection in various scenarios.

The development of macrocyclic hosts with high-affinity 1:2 recognition capabilities is crucial for advancing supramolecular chemistry and its applications. While cucurbit[8]uril (CB[8]) has long been recognized for its unparallel 1:2 binding affinity, its limitations-including poor solubility, difficulty to modify and lack of optical activity-have hindered broader utilization. Here, we introduce a class of enantiopure chiral macrocycles, RRRR- or SSSS-corral[4]BINOL (C[4]Bs), which exhibit remarkable 1:2 recognition properties in water that are comparable or even surpass CB[8]. Using UV-Vis, fluorometric, and isothermal titration calorimetry (ITC), we demonstrate that C[4]Bs form stable homoternary complexes with 11 singly positively charged planar aromatic guests, with binding affinities up to 1017 M-2. These ultrahigh affinities make C[4]Bs versatile alternatives to CB[8], offering advantages such as superior water-solubility, ease of structural modification, and strong fluorescence. Furthermore, the unique chiral nature of C[4]Bs enables efficient fluorescent discrimination of chiral substrates and chirality transfer to non-chiral dyes, resulting in strong circularly polarized luminescence (CPL) with |glum | values up to 1.1 ×10-2. This study establishes C[4]Bs not only as powerful hosts for aqueous-phase supramolecular complexation but also as a promising platform for developing chiral functional materials.

Photodynamic therapy (PDT) has been employed as a noninvasive treatment option for bladder cancer due to its controllability and minimal toxicity. However, the efficacy of PDT is often compromised by the hypoxic microenvironment of solid tumors. To address this challenge, our research is dedicated to developing a Ru-Se-Ce6 nanoreactor that combines the photoresponsiveness of Ru-Se coordination bonds and the reactive oxygen species (ROS) triggered by diselenide bonds, achieving dual-controlled release of the photosensitizer to enhance PDT effectiveness. The photoresponsive and catalytic characteristics of the nanoreactor were validated through synchrotron radiation and density functional theory calculations. Under laser irradiation, a metal-to-ligand charge transfer (MLCT) within the ruthenium complex leads to the cleavage of the Ru-Se bond, resulting in the liberation of the ruthenium complex, which significantly improves the O2 generation from H2O2 in the tumor microenvironment (TME). In vivo assessments demonstrated that Ru-Se-Ce6 disrupted the mitochondrial membrane potential via excessive ROS production, leading to cell cycle arrest and apoptosis. Additionally, Ru-Se-Ce6 has revealed significant tumor suppression in subcutaneous and orthotopic bladder tumor models while exhibiting good biocompatibility. These findings propose a potent and innovative approach for bladder cancer therapy.

Catenanes, interlocked molecular architectures, hold promise for molecular machines and catalysis, yet constructing complex topologies from multicavity cages remains challenging. Herein, we report the selective synthesis of an interwoven dimeric catenane comprising twin-cavity organic cages, achieved through a one-pot reaction between a trialdehyde planar panel and a triamine linker. This efficient synthesis is rationally guided by our probabilistic model. The model begins with a topological analysis that captures the essential spatial arrangement of the planar panels, which provides the main driving force for catenane formation and defines the interwoven and chain-like topological isomers. A probability density function that accounts for the π-π stacking interactions between the planar panels is then incorporated into the probabilistic model, enabling the semiquantitative prediction that the interwoven isomer is predominantly favored over the chain-like counterpart. Single-crystal X-ray diffraction unambiguously confirms the interwoven structure, revealing the stabilizing π-π stacking between the panels. This integrated theoretical-experimental approach offers a rational strategy for the selective one-pot synthesis of sophisticated interlocked architectures among various isomers.

Terpyridine-lanthanide (tpy-Ln) metallo-supramolecular polymers have garnered significant attention in supramolecular chemistry, coordination chemistry and materials science on account of the rigid structure, tunable electronic properties and strong coordination ability of tpy, as well as the unique electronic configuration and remarkable optical, magnetic properties of lanthanides. Over the past decade, the development of tpy-Ln metallo-supramolecular polymers has experienced rapid growth. This review provides an overview of recent progress in tpy-Ln metallo-polymers, covering both crystalline structures and amorphous forms. We focus on the synthesis of these metallo-polymers, with particular emphasis on their structural diversity and self-assembly strategies. Notably, we highlight their promising applications as luminescent materials, chemical sensors, and magnetic materials. Ultimately, this review aims to inspire further exploration into the rational design and synthesis of functional tpy-Ln metallopolymers with enhanced structural precision and enriched functionality, paving the way for their integration into emerging technological applications.

The expanding use of ionizing radiation in medical, therapeutic, and industrial applications drives the need for effective, lightweight, biocompatible, and metal-free radioprotectors. Melanin, a natural radioprotector, functions through direct radiation attenuation and radical quenching, making the synthesis and optimization of melanin-inspired materials a key research focus. Though polydopamine (PDA) is the predominant eumelanin mimic, its radioprotective efficacy requires improvement. Employing a heterocycle-engineering strategy, we designed and synthesized poly(benzo[b]selenophene-5,6-diol) (PDOPSe), which achieves the complete replacement of nitrogen in polydopamine (PDA) with selenium. We found that PDOPSe, though inspired by conventional PDA, exhibits enhanced radical scavenging and γ-ray protection performance than PDA. Provocatively, PDOPSe represents a new subtype of melanin enabled by heterocyclic engineering using chemical principles. This work provides an invaluable addition to the existing heterocycle library in melanin science, and broadens the functional diversity of Se containing polymers.

Highly emissive metallacages that generate reactive oxygen species (ROS) are important to synergistic cancer therapy, but it is still challenging to balance the emission and phototheranostic properties. Herein, a metallacage of DTPABT-Mc is prepared. It is observed that emission in the near-infrared region from 600 to 1000 nm with a high photoluminescence quantum yield value of 7.92% in solids is recorded for DTPABT-Mc. In addition, the ability to produce both type I and type II ROS under light irradiation is also observed, leading to potential application in photodynamic therapy (PDT) and chemotherapy. After that, 4T1@DTPABT-Mc-NPs, covering DTPABT-Mc nanoparticles with 4T1 cell membranes, are prepared to enhance their tumor-targeting ability. This finally results in effective therapeutic performance in vivo, effectively inhibiting tumor growth. These results suggest that DTPABT-Mc-NPs exhibit excellent synergistic therapeutic effects by combining PDT and chemotherapy, providing new ideas to design agents for diagnosis and therapy in the future.

Helicoidal structures, inherently chiral when adopting a preferred-handed conformation, hold great promise for a variety of applications. However, the rational design and synthesis of helicoidal structures with controlled handedness at the molecular level remain formidable challenges, which further limit the comprehensive understanding of multiscale chirality transfer within such hierarchical systems. Herein, we incorporated (-)/(+)-pineno-fused 2,2 ':6 ',2 ''-terpyri-dine into polymer backbones, and constructed metallo-helicoids with preferred-handed conformations. Chiroptical studies and direct visualization of the screw-sense of metallo-helicoids elucidate the hierarchical chirality transfer, ranging from chiral center to coordination junction, helicoidal surface, entire helicoidal backbone, assembly of multiple helicoid chains, and ultimately extending to interactions with achiral guests. Moreover, super-helices as several strands of metallo-helicoid chains were reversibly formed by treating/removing water from the polymer solution, leading to an inverse screw-sense compared with individual metallo-helicoids. Such super-helices are further able to induce the chiroptical activity of achiral dye molecules via intermolecular electrostatic interactions, thereby resulting in a significant enhancement of circularly polarized luminescence. Our study not only enables precise control over the handedness of metallo-helicoids but also serves as an ideal platform for investigating chirality transfer across a wide range of length scales.

Understanding the roles and dynamic evolution of active species represents a crucial yet challenging frontier in catalysis research, particularly in systems involving in situ-formed nanoclusters. Owing to the multimetallic nature of soluble nanoclusters, elucidating their distinct catalytic mechanisms, which differ fundamentally from those of conventional homogeneous molecular catalysts or heterogeneous surfaces, has emerged as a critical scientific priority, though this field remains largely unexplored. Herein, we demonstrate a nickel-catalytic system that achieves the regioselective double hydroboration of unsymmetrical internal alkynes with pinacolborane (HBpin), enabling efficient synthesis of sterically congested quaternary 1,1-diboryl alkanes. Mechanistic studies reveal that the catalytic activity originates from in situ-generated Ni nanoclusters, which uniquely activate multiple HBpin simultaneously and enable geminal (H, H) and (B, B) addition to alkynes. This proposed gem-addition mechanism diverges fundamentally from classical sequential double hydroboration pathways mediated by monometallic centers, highlighting the advantages of polynuclear architectures in unlocking unprecedented reactivity and catalytic pathways.