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Two-dimensional MXenes provide a versatile platform for engineering emergent quantum phases through surface chemistry. Here, we demonstrate via first-principles calculations that halogen functionalization enables strong-coupling superconductivity in Mo2C MXene monolayers. Among the systems considered (X = F, Cl, Br, I), only Br- and I-functionalized Mo2C are both dynamically and mechanically stable, exhibiting positive-definite phonon spectra and satisfying elastic stability criteria. Electronic structure analysis reveals metallic states dominated by Mo d orbitals with enhanced density of states near the Fermi level, providing favorable conditions for strong electron-phonon coupling (EPC). The calculated Eliashberg spectral functions show that low- and intermediate-frequency Mo-dominated phonon modes contribute predominantly to the EPC, driving the systems into the strong-coupling regime. Superconducting transition temperatures of 13.1 K for Mo2CBr2 and 18.1 K for Mo2CI2 are obtained within the Allen-Dynes formalism. Halogen functionalization simultaneously modifies lattice dynamics and redistributes electronic states, leading to a substantial enhancement of EPC compared to pristine Mo2C. Furthermore, electron doping serves as an effective tuning parameter, increasing the coupling strength and elevating the superconducting transition temperature above 27.5 K. In contrast, biaxial tensile strain induces competing effects between phonon softening and coupling enhancement, highlighting the interplay between lattice stiffness and pairing strength. These findings establish surface functionalization as a nanoscale design strategy for realizing tunable strong-coupling superconductivity in MXenes.

Controlling the fate of electrogenerated intermediates is central to achieving selective and reversible electrochemical processes in complex media. Although catalysts and electrode materials are routinely used to direct the fate of these intermediates, the electrolyte-despite its significant role in determining the electrochemical process's outcome-remains underexploited. In practice, electrolyte design remains primarily guided by bulk transport properties, such as viscosity and ionic conductivity, which mostly fail to capture the molecular-level interactions that determine intermediate fate. Here, we investigate a compositionally tunable choline-geranate-geranic acid ionic liquid (IL) electrolyte platform to determine how hydrogen-bond network organization regulates electrochemical behavior. Varying the geranic acid content reorganizes the hydrogen-bond network, as evidenced by infrared spectroscopy and variable-temperature 1H NMR, while preserving ionic character. Using the ferrocene/ferrocenium redox couple as a diagnostic probe, cyclic voltammetry reveals a transition from irreversible to near-reversible behavior with increasing geranic acid content, despite increasing viscosity and non-monotonic conductivity trends. Cyclic voltammetry, rotating-disk electrode, and variable-temperature measurements indicate that the irreversibility at low geranic acid content arises from a kinetically coupled chemical process rather than from transport limitations. Time-resolved UV-vis spectroelectrochemistry shows that ferrocenium is rapidly consumed in carboxylate-dominated environments but persists in hydrogen-bond-rich media, with protic cosolvents further suppressing redox-coupled reactivity. These results demonstrate that, within this IL series, electrochemical behavior is governed by the local solvation environment and its control over intermediate reactivity rather than bulk transport properties alone. This work establishes the electrolyte structure as a tunable handle for regulating the fate of electrogenerated intermediates, providing a structure-centric design strategy for ILs, deep eutectic solvents, and hybrid electrolytes.

Layered transition metal oxides (LTMO) are among the most promising materials for sodium-ion battery (SIB) cathodes, owing to good electrochemical performance and a variety of modification options for enhancement and refinement. However, drawbacks include irreversible structural and chemical changes, capacity decay, air and moisture instability, and mechanical and chemical incompatibility at the cathode electrolyte interface. Many ingenious solutions have been offered to alleviate these issues, including coating and doping strategies and morphological manipulation. Recently, sodium (Na) site substitution has attracted attention as an attempt to address these issues. Elements with similar ionic charge or radius compared to Na (Ca2+, Mg2+, K+, Li+) have been successfully inserted into the Na sites to act as stable structural and chemical pillars during desodiation. These "pillars" can increase structural stability and decrease capacity decay during cycling, especially in higher voltages, enhance Na kinetics, and alleviate detrimental redox reactions. The main drawback is decreased initial capacity and synthesis complications. In this perspective article, we explore the effects of the Na and O site doping in LTMO cathode materials in SIBs.

An accurate estimation of the molecular abundances of isomers in the interstellar medium (ISM) is necessary to unravel the underlying chemistry and physics. After the recent detection of both isomers of formic acid (cis- and trans-HCOOH) in dense dark cold clouds, their accurate molecular line modeling became of interest. The conditions of these environments do not necessarily follow the local thermodynamic equilibrium, thus taking into account the competition between the radiative and collisional processes is required. This involves knowledge of the rotational excitation data for collisions with the most abundant interstellar species - He and H2. In this paper, the first potential energy surface (PES) for the interaction of formic acid with He atoms is computed using the explicitly correlated coupled-cluster theory [CCSD(T)-F12]. The obtained interaction potentials for the two rotamers demonstrate qualitative similarities and high anisotropy. The global minima are found with V = -53.0 cm-1 and V = -46.0 cm-1 for cis-HCOOH and trans-HCOOH, respectively. Collisional excitation cross sections calculated for total energies up to 100 cm-1 demonstrate similar propensity rules for both isomers. Quantitative differences between the cross sections associated with the two rotamers are also discussed.

The influence of external magnetic fields on excited-state molecular dynamics remains largely unexplored despite its fundamental importance in photochemical and photophysical processes. To address this challenge, we develop a finite-magnetic-field ab initio nonadiabatic molecular dynamics framework based on Ehrenfest dynamics and gauge-including atomic orbitals. Analytical energy gradients in the presence of external magnetic fields are derived and implemented within a two-spinor formalism, enabling a unified treatment of orbital and spin angular momentum together with coupled electron-nuclear dynamics. The methodology is applied to the internal rotation of methyliminium cation (CH2NH2+) and the dissociation of H2 in an external magnetic field. Analysis of the nuclear forces reveals that these effects arise primarily from the magnetic-field-induced orbital Zeeman effect, while the direct Lorentz force contributes only minimally to the CH2NH2+ isomerization dynamics. For H2 dissociation, the two-spinor formalism captures both spin-coherence generation and magnetic-field-induced Larmor precession. These results establish a general framework for simulating magnetic-field-controlled nonadiabatic dynamics and provide new insights into the manipulation of photochemical and spin-dependent processes through external magnetic fields.

Developing environmentally benign anticorrosion coatings with high performance is essential for protecting mild steel infrastructure, yet reconciling chemical stability with long-term durability remains a major challenge. Herein, leveraging the π-π conjugation between quinacridone (QA) and graphene oxide (GO), we construct QA-functionalized GO hybrids and incorporate them into a waterborne epoxy (EP) coating to form an ordered self-assembled composite architecture. The resulting QA-GO/EP coating delivers an initial low-frequency impedance modulus as high as 4.53 × 106 Ω cm2 in 3.5 wt% NaCl solution-more than an order of magnitude higher than that of neat EP. Furthermore, electrochemical tests on scratched coatings reveal that QA-GO induces the formation of a stable passivation layer at damaged sites, effectively suppressing localized corrosion propagation. This work presents a new materials design paradigm for achieving ultra-corrosion-resistant epoxy coatings via controlled molecular-scale interactions.

Long-range interactions play a key role in (ultra)cold molecular collisions, yet describing them accurately remains challenging. In this work, we introduce a simple and general framework for the construction of a long-range potential energy surface that combines an analytical model with neural network (NN) representations. The physically correct radial asymptotic behavior is enforced analytically using a perturbative multipole model, while NNs are employed to capture the dependence of the multipole coupling coefficients on the internal molecular structure and relative orientation. Applications to the H3, Li3, and KRb-KRb systems demonstrate small fitting errors and physically reasonable extrapolation behavior. Quantum molecular dynamics calculations further show that the inclusion of long-range interactions significantly affects the reaction dynamics of the D + H2 and Li + Li2 reactions.

Interfacial physicochemical characteristics, electronic structure modulation, and charge transfer dynamics govern the efficiency of metal oxides and carbon systems for electrochemical reactivity and catalytic performance. In this study, density functional theory (DFT) calculations were used as a simplified local interfacial model to examine possible adsorption, charge redistribution, and noncovalent interactions at ZnO/ZnOH-carbon contact motifs. The molecular models are not intended to reproduce the full crystallographic, defect, or size-dependent electronic structure of the experimentally synthesised ZnO nanoparticles; rather, they provide qualitative insight into local ZnO-carbon and hydroxylated ZnO-carbon interactions. Charge analysis suggests that hydroxylated ZnO-carbon motifs can promote a donor-to-surface charge-transfer tendency compatible with caffeic acid oxidation. QTAIM analysis indicates that caffeic acid adsorption is stabilised mainly by noncovalent π-stacking and hydrogen-bonding interactions. These theoretical trends are discussed alongside cyclic voltammetric measurements using ZnO-modified and NaOH-pretreated ZnO-modified carbon paste electrodes. The surface morphology of ZnO nanoparticles was investigated by SEM, EDX, XRD and BET analysis. The modified electrode yields a low detection limit (0.0023 µM), high sensitivity (1.17 µA µM-1 cm-2), and diffusion-controlled kinetics. It exhibits good repeatability (RSD 0.65%), excellent reproducibility and stability (98.8% retention after 30 days).

Ionic liquids are versatile materials with great potential to improve existing technologies and enable new applications across a wide range of fields. Among this diverse material class, cations based on the imidazolium moiety are most frequently used, as they typically exhibit low melting points, high stability, and fast dynamics. However, imidazolium ionic liquids suffer from drawbacks in terms of toxicity, limited biodegradability, and complex synthesis. Here, we introduce novel protic formamidinium-based ionic liquids with two frequently used imide-type anions and compare their properties with structurally similar imidazolium counterparts. We investigate their thermal behavior, transport properties (viscosity, conductivity, and self-diffusion coefficients), and internal rotational dynamics. The previously unreported amidinium ionic liquids exhibit a generally favorable combination of physicochemical properties and outperform their imidazolium counterparts in most respects. These amidinium systems have lower melting points, arising from a lower enthalpy of melting that more than compensates for the lower entropy of melting, presumably due to altered hydrogen-bonding interactions. Moreover, the amidinium ionic liquids display significantly faster dynamics, especially at lower temperatures. Variable-temperature nuclear magnetic resonance measurements reveal that the rotation about the amidinium C-N partial double bond is strongly affected by the anion. These insights into the structure-property relationships of a novel cation class expand the chemical space of ionic liquids and enable the tailored design of next-generation ionic liquids to overcome current limitations across numerous applications.

Schwarzites are porous crystalline frameworks characterized by negative Gaussian curvature and three-dimensional periodicity. While originally proposed as carbon allotropes, recent advances in molecular preorganization and template-assisted synthesis concepts, together with the experimental realization of schwarzite-resembling molecular fragments, suggest that schwarzites may form a broader class of chemically tunable materials. In this work, density functional theory (DFT) calculations are employed to systematically investigate the structural, electronic, and optical properties of gyroid G688-schwarzites based on C, BN, SiC, Si, and Ge compositions. Cohesive energy analysis combined with ab initio molecular dynamics simulations demonstrates energetic and thermal stability of all investigated frameworks at room temperature, supporting their viability as metastable negatively curved crystalline phases. Electronic structure calculations reveal that all systems are semiconductors with composition-dependent direct bandgaps ranging from 0 to 2.87 eV, following trends analogous to those observed in their FCC counterparts. The optical response is strongly tunable across the ultraviolet and visible spectral regions, with distinct, element-dependent absorption, reflectivity, and refractive index profiles. These results establish chemical composition as an effective design parameter for tailoring the optoelectronic properties of negatively curved frameworks and provide first-principles guidance for future experimental efforts aimed at extending emerging bottom-up and template-based synthesis strategies beyond carbon-based schwarzites.

Herein, we reveal the temperature-dependent broadening of the Mott gap in layered α-RuCl3, together with a distinct transition in the range of 100-130 K, through surface morphology and electronic structure characterizations using scanning tunneling microscopy and scanning tunneling spectroscopy, respectively. Furthermore, layer-dependent measurements indicate an enhanced phase transition and Kitaev interactions with decreasing thickness. These results show that low-dimensional α-RuCl3 films differ from their bulk state owing to their unique structural and electronic properties, providing an ideal model platform for exploring Kitaev physics.

The selective hydrogenation of 5-hydroxymethylfurfural (HMF) to high-value chemicals is a crucial yet challenging reaction in biomass conversion. Herein, we systematically investigated the catalytic mechanisms of g-C3N4-supported Pd and Rh single-atom catalysts (SACs) for HMF hydrogenation, with a focus on the role of H2 activation modes in reaction pathways and selectivity. For Pd@C3N4, in the first hydrogenation of HMF, the Pd site activates HMF and H2 independently, preferentially hydrogenating the CO bond to yield BHMF via the Pd-mediated pathway. In the second hydrogenation of HMF, following BHMF formation, the catalytic system relies on the g-C3N4 support to heterolytically cleave H2via the Pd/N-cooperative pathway. With the help of the by-product H2O for H-transfer, the hydrogenation of the CC bond of BHMF toward BHMTHF is more favorable than the hydrogenation of the CH2OH group. In contrast, Rh@C3N4 enables the homolytic cleavage of H2 at the Rh center without the assistance of the g-C3N4 support and consistently favors the hydrogenation of the CH2OH group to produce DMF. The divergence in selectivity between Pd@C3N4 and Rh@C3N4 originates from the distinct H2 activation modes, particularly the accessibility of intermediate 16-the key species where H2 undergoes homolytic cleavage at the metal center. The strong binding of the species in 16 makes the first H attack at the CC bond energetically unfavorable, which makes the second H attack the rate-determining step with a much higher barrier than that for the CH2OH group's hydrogenation. This work reveals that the H2 activation mode acts as a decisive mechanistic switch to reverse reaction selectivity. The proposed principle offers theoretical guidance for the rational design of high-efficiency single-atom catalysts toward selective HMF hydrogenation.

Polyoxovanadate-alkoxides are a class of polynuclear earth-abundant transition metal compounds with highly tunable catalytic, redox, and magnetic properties. These species are ideal electroactive molecular agents for environmentally friendly energy storage applications, such as non-aqueous redox flow batteries. As such, it is fundamental to understand structure-redox relationships in the multielectron redox profiles of polyoxovanadate-alkoxides species. Here, we studied the redox properties of monomeric vanadate-alkoxide species that control the formation of two distinct chemical spaces with mix-valent clusters and fully reduced cyclic species. The accuracy of various density functional theory approximations and basis sets choices was benchmarked against domain-based local pair natural orbital coupled cluster, specifically DLPNO-CCSD(T). To further confirm the broader applicability of density functional theory in higher nuclearity species, we studied the redox profile of [(VV6-nVIVnO6)(O)(OCH3)12]4-n, [(Nb = O)(VV5-nVIVnO5)(O)(OCH3)12]4-n, [(M-OCH3)(VV5-nVIVnO5)(O)(OCH3)12]4-n (M = Ti, Zr, or Hf), and [(Fe-Cl)(VV5-nVIVnO5)(O)(OCH3)12]3-n hexanuclear polyoxovanadate-alkoxide species. The calculated redox profiles of these species were in good agreement with experimental data with an average absolute error of 0.11 V.

Low-dimensional hybrid lead iodide perovskites exhibit band gaps that are highly sensitive to subtle octahedral distortions, yet accurate prediction remains challenging under small-data regimes where traditional machine learning models tend to fail. Herein, we develop a collaborative machine-learning framework for two-dimensional (2D) lead iodide perovskites that integrates physically interpretable [PbI6]4--based structural descriptors, principal component analysis (PCA) for dimensionality reduction, multi-layer perceptron generative adversarial network (MLP-GAN) data augmentation (generating 1000 synthetic structures), and automated hyperparameter optimization. Using 107 single-crystal experimental data points, we benchmark nine regression models and demonstrate that GAN-based augmentation substantially improves model learning capability and generalization robustness. This study is designed to establish an interpretable data-augmentation strategy for small-data materials modeling and to test its applicability to band-gap prediction in 2D lead iodide perovskites.

Although pancake-bonded organic diradicals are promising systems for molecular spintronics, their magnetic exchange couplings, 2J values, are sensitive to thermal fluctuations due to their highly delocalized, multicenter bonds. Here, we present a systematic evaluation of 2J values and the corresponding mode-specific exchange-vibronic couplings, d(2J)/dQi, across a set of covalently tethered bi-Blatter diradicals. Specifically, we varied the peri-fused bridging scaffold that connects the monomer radicals to 1,8-naphthalene, 5,6-acenaphthylene, 1,8-anthracene and 4,5-phenanthrene, allowing us to investigate how strain tunes magnetic interactions. To do this, we first resolve the methodological challenge of calculating accurate singlet-triplet gaps, by demonstrating that spin-flip time-dependent DFT, SF-TDDFT, and multireference single-point calculations performed atop broken-symmetry DFT, BS-DFT, geometries yield excellent quantitative agreement with experimental 2J benchmarks. The bridge topology dictates the static ground state, switching the coupling from strongly antiferromagnetic in the phenanthrene and naphthalene scaffolds to weak coupling in the anthracene analogue. We probe the magnetic exchange response by displacing the geometries along low-frequency normal modes. For these dynamic properties, BS-DFT provides overly-large and unphysical exchange-vibronic gradients as well as thermally-induced 2J fluctuations. By contrast, SF-TDDFT accurately tracks the multireference methods, both in sign and magnitude. We find that the exchange-vibronic coupling is tied to only a few low-frequency lateral shearing and inter-deck compression modes. By connecting the d(2J)/dQi gradients with harmonic thermal displacement models, we provide insights for suppressing thermally driven fluctuations in organic spintronic architectures.

A unified deep generative framework for surrogate-guided molecular discovery across diverse molecular spaces is presented to connect forward property prediction with property-oriented candidate generation. A high-accuracy surrogate predictor based on message-passing neural networks is decoupled from heterogeneous generators, including sequence models and diffusion models, and integrated into a closed-loop strategy of generate, score, select, and regenerate to progressively enrich high-performing candidates without modifying the underlying model architectures. The framework is evaluated on three chemically distinct tasks involving the detonation velocity of energetic materials, the binding affinity of BACE-1 inhibitors, and the effective permeability of macrocyclic compounds. Consistent enrichment of molecules satisfying predefined property thresholds is achieved across all datasets. Diffusion models perform better in small and rigid systems, whereas SELFIES-based sequence models exhibit stronger structural stability in macrocyclic and topologically complex spaces. These results demonstrate the generality and transferability of the unified surrogate-guided molecular discovery framework.

Proteins transduce thermal stress into electrical signatures through coupled changes in hydration, interfacial polarization, and charge transport. Here, we introduce a dynamic non-faradaic electrical impedance spectroscopy (NFEIS) approach that resolves protein unfolding in real time and yields a quantitative impedance-hysteresis marker of metastability and irreversibility. Using a temperature-programmable coplanar microelectrode, we measure non-equilibrium impedance trajectories in real time during continuous 298 K to 373 K ramps (single-frequency), while isothermal equilibrium spectra at selected setpoints (253 K to 343 K) provide auxiliary constraints on permittivity and resistance evolution. Dynamic measurements reveal a reproducible hysteresis loop that encodes thermal-history-dependent damage, while dielectric relaxation time analysis extracts redistribution of relaxation times (DRT) and Arrhenius analysis quantifies dc conductivity (σ0). Orthogonal assays (circular dichroism (CD), activity, ζ-potential, differential scanning calorimetry (DSC)) delineate three regimes: a native compact state (≤298 K) with high |Z| and low permittivity; a metastable window (298 K to 323 K) with early α-helical perturbation and high electrical sensitivity (slope d|Z|/dT = -23.75 Ω K-1); and an irreversible denatured state (≥323 K) with elevated permittivity, reduced |Z|, and an enthalpic transition. Heating produces a persistent ∼30% conductance increase, whereas cooling drives enthalpy-coupled dielectric reconfiguration, together defining a bidirectional relaxation-energetic map. This work advances NFEIS from static state sensing to trajectory-based, physics-informed stability metrics that are rapid, label-free, and microliter-scale, with direct relevance to formulation screening and cold-chain quality assurance of protein based biologics.

Weak interactions are ubiquitous and critically modulate the conformational flexibility of polymers. Here, we investigate polyborosiloxane (PBS), a supramolecular polymer renowned for its shear-stiffening behavior. A series of PBS samples with varying molecular weights were synthesized via a condensation reaction and characterized by GPC and FTIR spectroscopy. The nearly identical molecular weights of PBS and its PDMS precursor confirm the absence of significant side reactions. The trends observed in Si-O-B infrared band intensities correlate with the hydroxyl group content in PDMS, verifying the successful formation of PBS. These experimental results guided the construction of initial structural models. Low-energy conformers were identified through a multi-level computational approach combining high-temperature molecular dynamics sampling, semi-empirical pre-screening, and high-level DFT single-point energy calculations. Frequency calculations confirmed all optimized structures as true minima. Weak interactions were comprehensively characterized via advanced wavefunction analyses, including IRI based on AIM theory, energy decomposition analysis, atomic charge calculations, and ESP mapping. These analyses reveal that intramolecular hydrogen bonds are crucial for PBS conformational flexibility. Thermodynamic calculations further confirmed the stability of energetically favorable conformers. A key innovation lies in the integrated, multi-perspective visualization of weak interactions. Our findings provide fundamental insights into the physicochemical properties of PBS isomers and establish a robust protocol for studying complex polymer systems.

The precise regulation of surfactant performance through molecular architecture is crucial for advanced colloidal applications. In this study, a homologous series of ethoxylated dodecyl-ammonium quaternary salts with varying ethylene oxide (EO) chain lengths (n = 2, 5, 10, 15) was synthesized to explore the non-linear effect of hydrophilic group size on physicochemical properties. Static surface tension and thermodynamic analysis showed a shift in the adsorption driving force from micellization-dominated (|ΔGmic| > |ΔGads|) at low EO numbers to adsorption-dominated (|ΔGads| > |ΔGmic|) at high EO numbers. Dynamic surface tension measurements revealed a critical kinetic transition: short-chain variants (S1202) followed diffusion-controlled adsorption, whereas long-chain counterparts (S1215) displayed significant kinetic hysteresis due to an energy barrier associated with interfacial conformational reorientation. Microscopic analysis (TEM/DLS) confirmed morphological changes from irregular lamellae/rods to spherical and eventually rod-like micelles, driven by a reduction in the critical packing parameter. Notably, the EO chain length served as a "molecular tuner" for macroscopic behavior: S1210 achieved the best balance in wetting dynamics, while S1202 exhibited superior foam stability due to the formation of a dense, rigid interfacial film that effectively suppressed Ostwald ripening and drainage. Additionally, a unique charge reversal (negative Zeta potential) was observed for S1210, attributed to the specific adsorption of anions on the Hydrophilic head group. This work establishes a comprehensive "structure-kinetic-performance" framework, offering theoretical guidance for the design of tailored surfactants.