Substituents in supramolecular chemistry are usually treated as passive handles that tune solubility or reactivity rather than as active determinants of assembly pathways. Here we show that tosyl groups promote directional noncovalent recognition and thereby control both cocyclization selectivity and postassembly topology in pillararenes. Under otherwise identical conditions, brominated analogues give statistical mixtures in which the pillar[4 + 1]arene product appears at only 1-19% distribution, whereas tosyl-substituted monomers undergo pseudorotaxane-like preassembly that enables highly selective self-templated pillar[4 + 1]arene formation without added external templates. A crystallographic survey of 12 single-crystal structures (N = 12), together with VT NMR, SAXS, molecular dynamics (MD) simulations, and fragment molecular orbital (FMO) analysis, establishes a valency-topology relationship in which increasing tosyl valency drives a progression from discrete monomers to interpenetrated dimers and higher-order aggregates. This substituent-dependent behavior extends across a broader alkoxy series, indicating that the effect is not limited to a single monomer pair. Upon benzoquinone oxidation, the tosyl-containing copillar[4 + 1]arene undergoes temperature-dependent switching between interpenetrated and self-included states, accompanied by changes in aggregation, a charge-transfer spectral shift, and reversible thermochromism quantifiable by ultraviolet-visible (UV-vis) spectroscopy and smartphone colorimetry. These findings establish substituent identity as an active design parameter for constructing reconfigurable and functionally responsive macrocyclic systems.

A series of heteroleptic iron(III) spin crossover (SCO) complexes, [Fe(qsal-I)(qsal-X)]NTf₂ (X = F 1, Cl 2, Br 3, 5-OMe 4), have been synthesized. The complexes exhibit diverse SCO behaviors influenced by the conformational flexibility of the NTf₂− (bis(trifluoromethanesulfonyl)imide) anion. Magnetic studies reveal that 1 and 4 undergo complete SCO, with 4 showing a two-step transition indicative of mixed-spin states. In contrast, 2 and 3 are stabilized in the low-spin (LS) state. Single-crystal X-ray diffraction studies indicate that 1 and 4 crystallize in triclinic P1¯ with parallel 1D π–π chains connected by C−H···π interactions, facilitating SCO transitions. Conversely, 2 and 3 adopt a packing with angled chains (ca. 15°), locking the compounds in the LS state enforced by C−H···I interactions. The NTf₂− anion plays a key role in modulating these transitions, exhibiting temperature-dependent conformational changes (syn and intermediate) in 1 and 4, while remaining fixed in the syn conformation in 2 and 3. Notably, some magnetic transitions occur independently of structural changes, and vice-versa. These findings highlight the interplay between anion conformation, crystal packing, and magnetic behavior, offering new insights for the design of SCO materials with tunable properties.

Copper(I) thiocyanate (CuSCN) has emerged as an excellent hole-transporting semiconductor with applications spanning across electronic and optoelectronic fields. The coordination chemistry of CuSCN allows for extensive structural versatility via ligand modification. In this work, we have developed a synthetic method that reliably produces phase pure [Cu(SCN)(3-XPy)]n complexes (Py = pyridyl; X = OMe, H, Br, and Cl) in a 1:1:1 ratio to yield two-dimensional (2D) structures with a Cu-SCN network. The single crystal structure of [Cu(SCN)(3-OMePy)]n is also reported herein. Complexes with X = OMe and H show similar structures, in which the 2D layers are analogous to the buckled 2D sheets of silicene or blue phosphorene. On the other hand, for complexes with X = Br and Cl, their rippled 2D structures resemble the puckered 2D sheets found in black phosphorene. The variation of the electron-withdrawing ability of the substituent group is found to systematically shift the electronic energy levels and band gaps of the complexes, allowing the 2D CuSCN-based materials to display optical absorptions and emissions in the visible range. In addition, first-principles calculations reveal that the drastic change in the electronic levels is a result of the emergence of the Py ligand electronic states below the SCN states. This work demonstrates that the structural, electronic, and optical properties of 2D Cu-SCN networks can be systematically tailored through ligand modification.

A series of ionic quaternary ammonium bromides featuring triazole moieties, QAS-trzBn 4 , QAS-trzPic 4 , and QAS-trzBn 2 Pic 2 , were synthesized via Cu-catalyzed azide-alkyne cycloaddition (CuAAC) between propargyl-based ammonium bromide and benzyl- or 2-picolylazide. X-ray crystallographic analyses of QAS-trzBn 4 and QAS-trzBn 2 Pic 2 revealed strong interactions between Br- ions and both triazolyl H and methylene H atoms (+NCH2), as evidenced by short Br-···H contacts ranging from 2.68 to 3.00 Å. The catalytic activities of these compounds as bifunctional, single-component catalysts for the CO2/epoxide cycloaddition were evaluated under both atmospheric and elevated CO2 pressures. Notably, catalysts containing pyridyl-triazole groups exhibited superior catalytic performances compared with the benzyl-triazole-based catalyst, QAS-trzBn 4 . A substrate scope study using QAS-trzPic 4 under 20 atm of CO2 at 100 °C revealed that electron-deficient epoxide substrates were more active, yielding good to excellent conversions (88-100%) to cyclic carbonates within 6 h. Computational studies identified key binding modes in pyridine-substituted systems that position both the epoxide and CO2 in close proximity. In particular, the QAS-trzPic 4 -CO 2 -epoxide complex is more stabilized than its benzyl derivative, QAS-trzBn 4 -CO 2 -epoxide, due to favorable interactions of CO2 with the pyridyl substituents.

We developed a sensitive voltammetric sensor for detecting aromatic phenylenediamine (PD) isomers: para -phenylenediamine ( p -PD), ortho -phenylenediamine ( o -PD), and meta -phenylenediamine ( m -PD).

Gross primary productivity (GPP) describes total photosynthesis (carbon fixation) in an ecosystem and is key to the global land carbon budget. To reduce uncertainties in carbon accounting for different forest ecosystems, it is crucial to analyze the health and productivity of forested ecosystems. Plant functional traits, which are a combination of morphological, physiological, and environmental characteristics, have been shown to be predictive of forest ecosystem carbon dynamics. This study aimed to assess how well GPP can be predicted by remotely quantified functional traits across varying forested ecosystems. Airborne remote sensing observations and in situ flux tower measurements used in this analysis were acquired from selected forested sites from the National Ecological Observatory Network (NEON) data portal. We investigated hyperspectral indices and lidar derived products as proxies of remotely sensed plant functional traits. Average midday GPP around the date of flight was calculated by developing a relationship between night respiration and temperature and removing that component from the net surface-atmosphere CO2 exchange (NSAE). We applied multiple linear regression with a best subset approach for three trait classes: morphological and environmental traits from lidar, physiological traits from hyperspectral data, and a combined functional trait model. The best-performing model, using lidar and hyperspectral traits, included CHM mean, DSM standard deviation, PRI standard deviation, and WBI mean producing a R2 of 0.87, an adjusted R2 of 0.84, a PRESS R2 of 0.75 and RMSE of 3.48 mu mol CO2/m2/s. Results show that a combination of plant functional traits are important predictors of forest productivity.

Pyridine bis(carboxamide)-strapped pillar[5]arene capsules were synthesized with the serendipitous formation of macrotricyclic products. The structural integrity of the supramolecular capsules, determined by the specific orientation of a single nitrogen atom, controls the electronic properties of the confined binding cavity, facilitating length-selective recognition of aliphatic organic guests with nitrile, isocyanide, and amine functional groups with exceptional host-guest binding affinity and selectivity for 1,2-diaminoethane (Ka > 104 M-1) in a polar organic solvent.

A series of macrocyclic heteroditopic receptors was synthesized to investigate cooperative recognition of alkali-metal halide ion pairs. The receptors combine either a 1,3-bis-iodotriazole (XB) or 1,3-bis-prototriazole (HB) benzene scaffold for halide binding with poly(ethylene glycol)-based macrocyclic moieties for cation coordination. Intensive 1H NMR binding studies revealed that XB-functionalized macrocycles exhibit significantly higher halide affinities than their HB analogues, while increased macrocycle size enhances alkali-metal cation binding strength. Notably, the halide-bound 1·XB macrocycle induced strong positive cooperativity in lithium-ion recognition, with up to a 7-fold increase in binding affinity. Density functional theory (DFT) calculations suggest that electrostatic stabilization between cobound ions underlies this effect, with the most pronounced enhancement observed for the 1·XB@LiI complex. Solid-liquid extraction experiments further demonstrated the practical potential of the XB system, achieving efficient transfer of lithium halide salts into organic solution. These findings establish halogen-bonded macrocycles as effective platforms for cooperative ion-pair recognition and highlight their promise for applications in lithium salt recovery and recycling.

Three iron(III) spin crossover compounds, [Fe(salBzen-5-OMe)2]A, where HsalBzen-5-OMe = 2-[(2-benzylaminoethylimino)methyl]-4-methoxyphenol and A = Cl- 1, Br- 2, I- 3, have been synthesized and fully characterized. UV-vis spectroscopy reveals two LMCT bands corresponding to the LS and HS states in solution. X-ray crystallography indicates that the compounds crystallize in monoclinic P21/n or P21/c (1), (2) or tetragonal P43212 (3) phases. At room temperature, complexes 1 and 2 display HS FeIII centers, while complex 3 adopts an LS state. Notably, complexes 1 and 2 exhibit symmetry breaking, decoupling the phenomenon from spin crossover. A variety of intermolecular interactions, including C-Hpi, C-HO, N-HO, C-Hanion, and N-Hanion, are responsible for linking the cations and forming a 3D supramolecular network. SQUID magnetometry studies show that compounds 1 and 2 remain high spin down to 10 K, while complex 3 undergoes a gradual spin crossover above 350 K. Crystallization of 2 at lower temperatures and humidity gives a tetragonal phase P43212 (2') that exhibits a spin crossover profile very similar to 3. Moreover, the crystal structure of 2' reveals temperature-dependent modulation. These results highlight the significant role of counterions in modulating the magnetic properties of these compounds and demonstrate the independent control of symmetry breaking and spin crossover. This work offers valuable insights for designing advanced functional materials for molecular spintronics and materials science.

A Zn-metal organic framework has been synthesized, [Zn4(ad)3(BPTC)(H2O)4]center dot 0.75ad center dot 0.25NO3 center dot 2.5DMF center dot 2.5H2O (ZnAB MOF) (ad = adenine, BPTC = biphenyl-3,3 ',5,5 '-tetracarboxylic acid) and characterized by X-ray single crystallography. The crystal structure reveals a 3D framework with two differently sized channels with the structure confirmed by IR, TGA and elemental analysis. This MOF has also been prepared in the form of a MOF film on a Zn metal sheet in situ with one continuous layer 60 mu m thick. The materials fluoresce at 352, 433 and 355, 423 nm (lambda ex = 310 nm), for MOF powder and MOF film, respectively. The fluorescence is quenched by nitrofuran antibiotics allowing the MOF to be used in their detection. Specifically, the nitrofuran antibiotics nitrofurazone (NFZ) and nitrofurantoin (NFT) exhibit significant quenching. ZnAB MOF powder shows higher sensitivity than the ZnAB MOF film with higher fluorescence quenching, Stern-Volmer constant (KSV) and limit of detection (LOD). However, the ZnAB MOF film exhibits superior repeatability for nitrofuran detection. Fluo-rescence quenching of NFZ and NFT may occur via fluorescence resonance energy transfer (FRET) and/or photoinduced electron transfer (PET).

We report development progress of a Concurrent Artificially-intelligent Spectrometry and Adaptive Lidar System (CASALS) for topography swath mapping from space. The beam scanning was demonstrated by fast wavelength tuning and grating dispersion, and near quantum limited performance was measured at 1550 nm. A 1040 nm CASALS prototype is being developed for Earth science. The laser is rapidly tuned across 13 nm and carved into 2-ns pulses to scan 256 tracks. At the grating-spectrometer-based receiver, returns from each track are filtered spatially and spectrally and imaged onto a HgCdTe APD-array. The detected signals are time-division-multiplexed to only two high-speed analog-to-digital converters and range-gated to reduce data volume. The design can be adapted for gapless sub-meter resolution lunar swath mapping at 1550 nm. 3D imaging of landing site with 4 M footprints per second is enabled by inserting a 4-Hz 2D steering mirror. The lidar can also perform navigation measurements up to 100 km.

Compressive satellite LiDAR (CS-LiDAR) has been recently introduced as a radically different computational sensing and reconstruction approach for LiDAR sensing of Earth. It is based on NASA’s adaptive wavelength scanning LiDAR (AWSL) system. Unlike conventional 1D LiDAR methods, CS-LiDAR utilizes sparse coded laser illumination across a 2D field-of-view. The aim is to compressively capture Earth from hundreds of kilometers above, enabling computational 3D imagery reconstruction with resolution that is comparable to that attained with data collected from just hundreds of meters. The forward imaging model captures the light propagation phenomena affecting the photon pulses transmitted from the sensor to the Earth’s surface and back. This work enhances CS-LiDAR by integrating imaging spectroscopy into a multimodal system and employing a transformer network for the inverse imaging problem, driven by multimodal attention mechanisms. Emulations enabled by enormous observational LiDAR data of Earth, available from NASA’s G-LiHT imaging observatory, highlight the efficacy of methods developed.

The impact that the anion and alkyl group has on the electronic structures and magnetic properties of four mononuclear Mn(III) complexes is explored in [Mn(salEen-Br)2]Y (salEen-Br = 2-{[2-(ethylamino)ethylimino]methyl}-4-Br-phenol; Y = ClO4- 1 and BF4-·1/3CH2Cl2 2) and [Mn(salBzen-Br)2]Y (salBzen-Br = 2-{[2-(benzylamino)ethylimino]methyl}-4-Br-phenol; Y = ClO4- 3 and BF4- 4). X-ray structures of [Mn(salEen-Br)2]ClO4·0.45C6H14 1-hexane, [Mn(salEen-Br)2]BF4·0.33CH2Cl2·0.15C6H14 2-dcm-hexane, and 3-4 reveal that they crystallize in ambient conditions in the monoclinic P21/c space group. Lowering the temperature, 2-dcm-hexane uniquely exhibits a structural phase transition toward a monoclinic P21/n crystal structure determined at 100 K with the unit cell trebling in size. Remarkably, at room temperature, the axially elongated Jahn-Teller axis in 2-dcm-hexane is poorly defined but becomes clearer at low temperature after the phase transition. Magnetic susceptibility measurements of 1-4 reveal that only 3 and 4 show slow relaxation of magnetization with Δeff/kB = 27.9 and 20.7 K, implying that the benzyl group is important for observing single-molecule magnet (SMM) properties. Theoretical calculations demonstrate that the alkyl group subtly influences the orbital levels and therefore very likely the observed SMM properties.

This paper proposes an algorithm to enhance the resolution of satellite lidar data using Generative Adversarial Networks (GANs) under the hyperheight data cube framework. A super-resolution algorithm based on adversarial training is applied to overcome the challenges of long-range satellite lidar systems. The algorithm generates high-resolution super-resolved outputs from low-resolution inputs, improving the quality of several lidar representations such as canopy height models and profiles. This approach not only advances lidar-based models but also facilitates sophisticated lidar data analysis for various fields, such as environmental science, urban planning, and disaster management. The super-resolved lidar data provides a more precise depiction of the Earth's surface, opening up new avenues for research and applications in different domains. The framework's effectiveness was validated in the Florida Everglades National Park, where the resolution was increased from a 3m x 6m grid with 10m footprints to a 3m x 3m grid with 3m footprints, and the vertical resolution was enhanced from 0.5m to 0.25m.

We present the design and performance of a Concurrent Artificially-intelligent Spectrometry and Adaptive Lidar System (CASALS) for 3D imaging from Space. With a single fast wavelength tuning laser, CASALS accomplishes a 1,200 resolvable spots swath mapping by grating dispersion wavelength steering. Any subset of these 1,200 spots can be selected by wavelength switching. The validation operating principle was accomplished and reported in IGASS-2022. With configurable base design, we report the designs and progress of the CASALS airplane campaign with 256 contiguous ground spots. It is accomplished with a single fast tuning lase at 1040-nm, 1.152MHz tuning rate, and pulse modulated 2-ns on each wavelength. Return pulses are mapped to an eight-pixel detector array with single-photon sensitivity. The lidar returns are time-multiplexed to two outputs that are digitized with two 1-GSPS-digitizer. A grating spectrometer rejects solar background noise spatially and spectrally. We are developing a 1040-nm CASALS intended for multiple LEO orbit missions: Earth Venture Mission on ESPA Grande, STV Mission on ESPA Grande SmallSat, STV Mission on spacecraft equivalent to ICESat-2.

Supramolecular interactions are central to self-assembly. Recently, Liu and coworkers revealed that π–π interactions drive the self-assembly of a diamondoid superstructure with superior photophysical properties. This report highlights that careful molecular design of building blocks can aid in the construction of complex superstructures.

A series of three compounds [Fe(salEen-5-I)(2)]Cl 1, [Fe(salEen-5-I)(2)]Br 2, and [Fe(salEen-5-I)(2)]I 3 in which salEen-5-I = 2-{[(2-(ethylamino)ethyl]imino)methyl}-4-iodophenolate is reported. Magnetic studies reveal that 2 exhibits an abrupt 2-step spin crossover close to room temperature around 288 K, while 1 and 3 exhibit gradual incomplete spin crossover spanning over 200 K. The use of structural parameters A-C to describe the nearest and next nearest neighbor contacts allows us to rationalize not only the abruptness of the spin crossover but also the stepped nature of the spin crossover in 2. Comparisons with previously reported [Fe(salEen-5-Br)(2)]ClO4 and [Fe(salEen-5-I)(2)]ClO4 reveal that this magnetostructural relationship is applicable to a wider range of members of this family of complexes.