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Gas sorption and separation in porous materials is dependent on the host–guest binding within any given system. Now, the molecular details of cooperative binding between small hydrocarbons and a metal–organic framework, NOTT-300, at multiple sites have been elucidated by complementary scattering and diffraction techniques. This material is also capable of separating C₁ and C₂ hydrocarbons under ambient conditions.

Metal–organic frameworks (MOFs) combining the properties of the metal ions and organic ligands are been proposed for many applications. Here Quah et al. demonstrate multiphoton excitation fluorescence in MOF materials enhanced by high quantum yielding guest molecules and Förster resonance energy transfer.

Separation of xylene isomers is essential for the production of a wide range of materials, but current separation methods are energy intensive. Here the authors report separation of the three xylene isomers at room temperature, via refinement of the pore size in a series of porous MOFs at sub-angstrom precision.

Some flexible metal–organic frameworks are known to exhibit an adaptive behaviour as they convert between two stable forms in response to their environment. Now, a metal–organic framework based on nonlinear linkers has been shown to adopt a much more complex family of degenerate disordered configurations, which can be reversibly interconverted through guest exchange.

Membranes can be used for energy efficient organic liquid mixture separations. Here the authors use machine learning and transport simulations to predict the separation of complex mixtures such as crude oils by any linear polymer membrane.

Polymersomes with surface-integrated nanoparticles have potential in a range of applications, but are challenging to prepare. Here, the authors report a method for the preparation of such polymersomes by a hierarchical phase separation approach.

What happens to a crystal placed under a huge pressure? In the case of aluminium, it is now shown that the standard, low-pressure close-packed structure transforms into an open one, with incommensurate host–guest arrangement. The findings could have important implications for a wider range of elements.

The kinetics of multivalent interactions at interfaces is poorly understood despite its fundamental importance for (bio)molecular motion and molecular recognition events at biological interfaces. Here, directional spreading of multivalent molecules has been observed, and multiple surface diffusion mechanisms have been identified and dubbed walking, hopping and flying.

Gaining molecular-level insight into host–guest binding interactions is fundamentally important, but experimentally challenging. Here, Schröder and co-workers study CO₂–host hydrogen bonding interactions in a pair of isostructural redox-active V^III/V^IVMOFs using neutron scattering and diffraction techniques.

This work demonstrates how a biphenyl-like scaffold targets RNA through a common base displacement mechanism by optimizing π-stacking interactions within the binding pocket, helping to inform the design of novel RNA-targeting small molecules.

Perylene diimide-bithiophene macrocycles are electroactive and shape-persistent hosts. Here, the authors describe their self-assembly into a cellular organic semiconducting film whose voids are electrically sensitive to different guests, and which can function as the active layer in a field-effect transistor device.

Realizing efficient blue-emitting organic light-emitting diodes (OLEDs) with long operational lifetime is key to the development of future display technologies. Here, the authors report efficient host-guest and host-free OLEDs featuring designed carbene-metal-amide-type deep-blue photoemitters.

Glass-like supramolecular polymer networks with high compressibility and fast self-recovery are fabricated using host–guest crosslinkers with slow dissociation kinetics.

Understanding the structural dynamics of flexible metal-organic frameworks at a thin-film level is key if they are to be implemented in devices. Here, Fischer and colleagues anchor flexible MOF crystallites onto substrates and identify a structural responsiveness that is distinct to that of the bulk.

Porous materials are technologically important for a wide range of applications, such as catalysis and separation. Covalently bonded organic cages can now be assembled into crystalline microporous materials, and their porosity is found to be intrinsic to their molecular cage structure.

The defects at the perovskite/carrier transport layer interface pose significant challenges to the performance of perovskite solar cells. Here, the authors introduce a dual host-guest complexation strategy with Cs-crown-ether and ammonium salt, achieving a high PCE of 25.9% with superior stability.

Benzene is a genotoxic carcinogen with no safe level of exposure. Here, by creating and decorating a structural defect in a metal–organic framework to form MIL-125-Zn, a benzene uptake of 7.63 mmol g^–1 at 1.2 mbar is observed due to binding to Zn(II) sites.

Preorganization of catalysts and substrates can lead to significant rate enhancement—an effect often observed in enzyme catalysis. Now, a self-assembled nanosphere equipped with 24 guanidinium binding sites is demonstrated to strongly bind sulfonate-containing gold catalysts. Base-triggered co-encapsulation of carboxylate containing substrates leads to pronounced gating effects and dramatically enhanced reaction rates.

An interconverting system of three distinct stereoisomers of a cuboctahedral Co^II-based cage is able to regulate the binding affinities of large anionic guests. Through cooperative templation with fullerene guests, the cage converts into a desymmetrized cage that in turn exhibits positive cooperativity in binding of an icosahedral anion; this interaction is anti-cooperative in the fullerene-free parent.

Cartilage-targeted gene therapy is dependent on delivery efficiency. Here, the authors develop non-pathogenic, virus-inspired lipopeptide-based nanoplatforms to deliver nucleic acids to cartilage with increased transfection efficiency over conventional lipid nanoparticles.

Single-layer organic light-emitting diodes based on thermally activated delayed fluorescence are demonstrated, exhibiting pure-blue emission, high quantum and power efficiencies, and operational stability.

Assembly of MOF-on-MOF hybrids with complex structures and properties is of interest, but achieving sophisticated ternary heterostructures is challenging. Here, the authors synthesize three types of ternary MOF-on-MOF heterostructures with tunable complexity via a multiple selective assembly strategy.

How the pulvinar represents complex visual information, its functional topography, and its relationship to cortical processing of visually presented objects remains unclear. Here authors show that responses to natural scenes in the human pulvinar reveal organized spatial maps for both low-level visual features, such as local contrast, as well as high-level visual features, such as bodies and faces.

The development of advanced electrocatalysts with high efficiency and longevity is essential to alleviate the energy crisis. Here, the authors report an atomic editing strategy to access atomically dispersed, heteronuclear triatomic Fe and Co sites to endow improved activity and stability.

The interconversion of the two spin isomers of formaldehyd has been studied in the gas phase but has never been observed experimentally in the condensed phase. Here the authors report the encapsulation of formaldehyde inside C60 cages and observe spin-isomer conversion of the formaldehyde guest molecules in the cryogenic solid state.

Challenges in mapping modern molecular and anatomical datasets into a common atlas are not fully addressed. Here authors present approaches to aligning multimodal neuroimaging data and quantifying geometric variability. Authors also make sure open-source code, dataset standards, and a web interface are available, enabling large scale integration of datasets essential to modern neuroscience.

Catenated cages are challenging synthetic targets in chemistry. Here, the authors employ a multi-component coordination strategy using a Pt(II) heteroligation to construct a cyclic bis[2]catenane metallacage, which could be reversibly transformed between the catenated structure and the bis-metallacage.

Anion recognition in competitive, aqueous media remains a critical challenge. Bulk and local solvation models for anion recognition events are herein explored, as well as targeted design approaches to retain strong anion binding in highly polar media.

A coordination cage has been prepared that self-assembles through second-order templation. Peripheral perchlorate or hexafluorophosphate template anions direct the formation of a hollow prism whose central pocket was able to bind a small anionic guest such as halide or azide, in a manner reminiscent to signal transduction in biological systems.

Nitrogen oxides are major air pollutants; capture and abatement technologies exist but they typically involve toxic species or precious-metal catalysts. Now, a metal–organic framework has been shown to store NO₂ dimers selectively, and to separate NO₂ from other gases under wet conditions. Treatment with water in air leads to conversion of NO₂ into HNO₃—an important feedstock for fertilizer production—with full recovery of the host.

Knowledge of the thermodynamic potential is crucial to characterize the macroscopic state of soft porous crystals. Here, the authors present a generalized thermodynamic approach to construct the Helmholtz free energy and identify the conditions under which a material becomes flexible.

A topologically non-trivial metallosupramolecular structure is formed by a Pd₄L₄ complex in which interweaving and twisting of the ligands results in both Solomon's Link and figure-of-eight ring motifs. In the solid state, six of these complexes assemble into a hollow spheroid that closely resembles a stellated truncated hexahedron.

The construction and operation of interlocked molecular machines often rely on the mutual recognition of different building blocks through a range of non-covalent interactions. Researchers have now shown that the versatility of bipyridinium systems can be increased by taking advantage of the complexes formed between their radical cations; with this approach they have been able to make electrochemically switchable bi- and tristable rotaxanes.

Metastable cubic ice has been identified in several conditions relevant to geo and astrochemistry, but was always characterized by stacking disorder. Here the authors synthesize a hydrogen hydrate and degas hydrogen, obtaining pure non-defected cubic ice, observed by X-ray and neutron diffraction.

Individual hydrogen bonds are weak, so self-assembling multiple components via hydrogen bonding is a significant challenge. Here the authors report a robust, enantiopure nanocapsule held together by 48 cooperative hydrogen bonds, and use it for the selective binding of C₇₀.

Volatile organic compounds such as benzene are toxic pollutants that cause health issues even at trace concentrations. Here, a double-walled metal–organic framework is presented that demonstrates high uptake at very low pressures (<10 Pa), allowing the removal of benzene to below acceptable indoor limits.

Biological systems are made up of complex networks that can respond to stimuli and function across relatively long distances in molecular terms. Now, it has been shown that a local disruption (the isomerization of just a single azobenzene unit) at the interface of supramolecular glassy polymersomes can immediately spread through over 500 bonds, significantly changing membrane permeability and enabling controllable release of guest molecules.

Interlocked molecules commonly include one (or more) monocyclic component — examples comprising bicyclic or tricyclic structures are much more rare and usually involve metal–ligand coordination or additional templates. Now, the dynamic self-assembly of twenty organic molecules in a one-pot synthesis has been shown to produce tetrahedral covalent cages, which interpenetrate during the process to form triply interlocked dimers.