Computational insights into the corrosion inhibition mechanism of daidzein on Al(AA7075) alloy in NaCl solution: A DFT and molecular dynamics study.

The reaction of ethyl 4-chloro-3-oxobutanoate with phenyl isothiocyanate in sodium ethoxide afforded thiophene derivative 4. Single-crystal X-ray diffraction showed space group P-1 with one independent molecule in the asymmetric unit. Hirshfeld surface analysis revealed that crystal packing is dominated by H∙∙∙H (48.1%) and O∙∙∙H (20.9%) interactions, as well as weak van der Waals contacts. Density functional theory (DFT) calculations indicated a HOMO-LUMO gap of 4.862eV, suggesting a moderate softness, polarizability, and charge-transfer potential. Molecular electrostatic potential mapping and Fukui function analyses identified C2, N9, O16, C13, O7, C11, C15, C10, and O8 as favorable sites for electrophilic attack, while C1, S5, C3, and C6 were predicted as nucleophilic centers. NBO and Mulliken charge calculations supported the findings by emphasizing the strong accumulation of electron density on heteroatoms. In silico toxicity and drug-likeness evaluation suggested the absence of mutagenic, tumorigenic, or reproductive risks. Structural and computational findings underscore the stability, electronic responsiveness, and potential biological relevance of thiophene derivative 4.

Experimental and theoretical investigation into the structural and anticancer properties of sulfadiazine-derived azo dyes: A DFT and molecular docking approach.

High-voltage polyanionic cathodes, such as Na3V3(PO4)2F3 (NVPF), are pivotal for high-energy-density sodium-ion batteries but are fundamentally constrained by severe parasitic reactions at the desodiated interface. These reactions driven by unsaturated vanadium sites and solvent enrichment cause rapid capacity fade. Herein, we propose a molecular interfacial engineering strategy using rationally designed organic phosphate additives. These additives stabilize vanadium via π-d orbital hybridization and regulate the interfacial microenvironment through three-dimensional steric shielding, passivating reactive species, and suppressing solvent enrichment. Guided by a descriptor-driven screening process (Mulliken charge, van der Waals volume, O 2p band center, ΔE (O 2p band center-V 3d band center)), tris(trimethylsilyl) phosphate (TMSP) is identified as the optimal electrolyte modifier. The TMSP-tailored electrolyte promotes in situ formation of a thin, compact, and inorganic-rich interphase on both the NVPF cathode and the hard carbon (HC) anode, effectively mitigating vanadium species dissolution and parasitic side reactions. Consequently, the 4.3V NVPF||HC pouch cell can deliver exceptional cycling stability, retaining 85.24% of its capacity after 1500 cycles (416.7 days) at 0.3 C, and achieve a high energy density of 161Wh kg- 1. This work establishes a design principle that couples orbital hybridization with steric shielding to construct ultra-stable interfaces in high-voltage battery systems.

Electronic circular dichroism (ECD) stands out as a highly sensitive spectral probe for chiral systems, facilitating molecular configuration determination, analysis of metal-ligand interactions, and the design of chiral optical materials. However, traditional machine learning struggles to predict ECD spectra of metal complexes accurately because multiple coupled electronic transitions, complex local-environment perturbations, limited data availability, and model interpretability constraints introduce significant uncertainty. To address these issues, we propose a physics-inspired machine learning framework that integrates "femtosecond charge dynamics - ECD spectra - electronic transitions." This approach enables predictions of chiral spectra for silver-based metal complexes with quantitatively close to the corresponding TDDFT references for the present data set but at just 1/470th of the computational time. This framework serves as a interpretable and computationally efficient framework within the present silver-based chemical space for tasks such as absolute configuration determination, chiral catalysis screening, and reverse design of optical materials. It achieves precise mapping between real-time femtosecond charge dynamics and the ECD spectra of chiral silver clusters and Ag-DNA complexes. A systematic evaluation using a self-constructed data set reveals that our MC-HG model increases computational speed by approximately 470 times compared to traditional TDDFT methods. Furthermore, the PSF-ECD model enhances spectral shape similarity by a factor of 3 and reduces error indices by 45% compared to single traditional machine learning models. By integrating the transition contribution map (TCM) with Mulliken charge flow visualization, we establish an interpretable link between learned spectral shapes and specific orbital transitions and charge transfer channels. This offers an efficient pathway for evaluating the chiral optical response of metal complexes without the need for repeated real-time TDDFT calculations.

The increasing scarcity of freshwater in mining regions of Chile has promoted the use of low-quality water as an alternative in flotation processes, significantly modifying their operating conditions. In particular, high salt concentrations and the presence of dissolved ionic species may interfere with the adsorption of collectors on chalcopyrite, thereby reducing its hydrophobicity. In this context, the present study analyzes the adsorption characteristics and the mechanistic role of selected representative ionic species on the chalcopyrite surface. To this end, simulations based on density functional theory (DFT) were employed to describe the interaction between the chalcopyrite (112) surface and Na+, Ca2+, Mg2+, and OH− ions. After geometric convergence of the optimized structures was achieved, adsorption energies, charge redistribution based on Mulliken population analysis, and the final structural configurations were evaluated for each case. The results revealed clearly differentiated behaviors among the ionic species considered. The OH− ion exhibited a localized and specific interaction with metal-centered sites. By contrast, Ca2+ and Mg2+ show stable adsorption near sulfur atoms, indicating a higher affinity that may lead to the occupation or blocking of active surface sites. Meanwhile, Na+ displays a weak interaction without inducing significant structural modifications. Overall, these findings provide an atomistic-level interpretation of how ionic species present in low-quality water can influence the surface reactivity of chalcopyrite under flotation operating conditions.

The molecular and pharmacological potential of 2-phenylacetophenone was examined using DFT-based B3LYP/6-311++G(d,p) computations along with integrated spectroscopic and molecular docking analyses. The compound’s optimized geometry and vibrational modes were validated using FT–IR and FT–Raman spectra, while UV–Vis transitions were calculated via TD–DFT and matched with experimental data. The chemical environments of 1H and 1³C nuclei were assessed using GIAO-based NMR calculations. Mulliken Population Analysis (MPA) and Natural Population Analysis (NPA) were performed to evaluate the charge distribution within the molecule, revealing significant electron-rich and electron-deficient regions. Frontier molecular orbital (FMO) analysis, electrostatic potential (ESP) mapping, and Hirshfeld surface analysis revealed electronic characteristics and reactive regions. Topological parameters (ELF, LOL, RDG) confirmed electron delocalization and non-covalent interactions. NBO analysis indicated strong donor–acceptor interactions, with a maximum stabilization energy of 22.14 kJ/mol. Global reactivity descriptors suggested promising bioactivity. Drug-likeness evaluation satisfied Lipinski’s rule, and molecular docking showed effective binding to neurodegenerative targets (AChE: 2H9Y and MAO-B: 4F1T), supporting its therapeutic potential against Alzheimer’s and Parkinson’s diseases.

Ammonia is a harmful air pollutant that is frequently released by industrial activities, agricultural, and waste treatment facilities, posing major threats to human health and the environment. The development of sensitive, selective, and longlasting ammonia sensors is thus critical for accurate air-quality monitoring. Choline chloride-glycerol-based deep eutectic solvents (DESs) are presented as attractive sensing media due to their strong hydrogen-bonding capacity, customizable physicochemical features, and environmental friendliness. DFT computations were used to study the atomistic interactions between ammonia and the choline chloride-glycerol DES. Geometry optimizations were carried out to determine the most stable DES-ammonia complexes, followed by extensive electronic structure investigations. Charge redistribution was visualized using molecular electrostatic potential (MEP) maps, which also identified preferential interaction sites for ammonia adsorption. Mulliken charge analysis offered quantitative information about charge transfer pathways during complex formation, whereas frontier molecular orbital (HOMO-LUMO) study indicated changes in electronic characteristics relevant to sensing performance. The findings show strong and directed interactions between ammonia and DES components, which are predominantly regulated by hydrogen bonding and electrostatic forces, resulting in notable changes in electronic structure upon ammonia attachment. These results demonstrate the suitability of choline chloride-glycerol DESs as active materials for ammonia sensing. Future research will concentrate on dynamic simulations, temperature impacts, and experimental validation to connect atomistic discoveries with practical sensor development.

Organometallic compounds, particularly organotin compounds, are of crucial importance in catalysis and molecular stabilization due to the polarity and reactivity of Sn–C bonds. In order to gain a detailed understanding of the structural and electronic behavior of organometallic compounds, it is essential to adopt an integrated approach that includes theoretical simulations. This work comprises an in-depth theoretical analysis using Density Functional Theory (DFT), aimed at elucidating the molecular structure, electronic properties, and spectroscopic attributes of the crystalline complex (2-hydroxybenzoato-κO) triphenyl (triphenylphosphine oxide-κO) tin (IV), with the formula C₆H₄ (OH)CO₂SnPh₃OPPh₃. Furthermore, the study of Mulliken and NBO charge distributions and global descriptors indicate that the complex exhibits moderate electronic stability accompanied by a pronounced electrophilic character. Frontier molecular orbital (HOMO–LUMO) analysis highlights an intramolecular charge transfer (ICT) from the donor ligand to the acceptor center across the entire molecule. In addition, theoretical spectral analysis, including infrared (IR) spectra, further validates the chosen computational approach. These results demonstrate the importance of ligands in tuning the electronic and spectroscopic properties of the tin(IV) complex, emphasizing the relevance of such molecules for potential applications in materials chemistry and molecular sciences.

Designing nonlinear optical (NLO) materials that integrate high stability with broad tunability is essential for photonic technologies such as laser protection and dynamic light control. Herein, we utilize photoactive ligand coumarin to deliver photogenerated electrons and stabilize the reduced state in the vanadium-based nanocluster (C3), significantly enhancing its nonlinear refraction and prolonging the response stability. Density functional theory reveals that coumarin narrows the band gap (from 0.43 to 0.40 eV), promotes charge transfer, and stabilizes reduced vanadium centers (the average Mulliken charge decreases from 1.127 to 1.112), enabling C3 to retain more than 85% of original NLO efficiency after 24 h. Moreover, C3 exhibits self-initiated polymerization behavior, forming solid-state films that sustain strong nonlinearity for hours and allow multiple UV reactivation cycles. Therefore, this work provides a general design strategy for achieving highly tunable and robust NLO materials by leveraging photoactive organic ligands to transfer electrons and stabilize reduced electronic states in metal oxide nanoclusters.

Boron carbide (B₄C) is a high-performance material valued for its hardness, yet it is susceptible to local amorphization under high-stress conditions, degrading its mechanical strength. Aluminum doping has been proposed to mitigate this phenomenon. This study investigates the electronic effects of incorporating aluminum into the intericosahedral chain using isolated cluster models: undoped B72(C-C-C) and Al-doped B72(C^Al^C). Results demonstrate that aluminum substitution induces pronounced electron density redistribution and strong electronic polarization. The aluminum atom loses electron density, becoming positively charged (+ 0.611 e⁻), while neighboring carbon atoms accumulate density. This asymmetry creates a significant uncompensated dipole moment of approximately 2.04 D in the doped cluster, which is entirely absent in the undoped structure. This polarization effect likely influences the spatial distribution of Al atoms in the solid phase and, consequently, affects the mechanical, thermal, and electronic properties of aluminum-modified boron carbide. Calculations were performed using Density Functional Theory (DFT) with the hybrid B3LYP functional and the STO-3G basis set. The molecular orbital method, using a linear combination of atomic orbitals (LCAO-MO), was employed to analyze the three-dimensional electron density distribution. To represent bulk material behavior, atomic coordinates were adopted from prior periodic boundary condition calculations without further optimization. Mulliken population analysis was used to determine atomic charges and electron populations. All computational procedures and electronic property calculations were conducted using the GAMESS'09 software package and the Atomic Simulation Environment (ASE), while visualizations were performed using the ChemCraft software package.

Black phosphorus (BP) holds promise for gas adsorption, but intrinsic BP often exhibits limited performance. To enhance the limited adsorption performance of intrinsic black phosphorus (BP) towards volatile organic compounds (VOCs), this study investigated the adsorption behaviors of BP doped with ten elements using density functional theory (DFT). Simulations reveal that intrinsic bilayer BP exhibits formaldehyde adsorption energies ranging from - 0.0082 to - 1.6439 eV. Doping significantly improved this performance; notably, Al-doped BP achieved an adsorption energy of - 4.7037 eV at the R-site, nearly tripling the intrinsic value. Mechanism analysis indicated substantial electron transfer from the modified BP to formaldehyde, with Na-, Li-, and Al-doped systems demonstrating charge transfers of - 0.74 e, - 0.71 e, and - 0.70 e, respectively. This redistribution of electron density markedly strengthened interactions with polar molecules. Consequently, the doped systems displayed superior adsorption efficacy for oxygen-containing VOCs compared to non-polar ones, with Li-doped BP attaining a maximum adsorption energy of - 3.8432 eV for acetaldehyde. These findings provide theoretical insights into tuning BP's electronic structure via doping to develop high-performance 2D adsorption materials. All calculations used DFT with GGA-PBE and LDA. A plane-wave basis set (480 eV cutoff) and ultrasoft pseudopotentials were used. The Brillouin zone was sampled with a 2 × 2 × 2 k-point grid. Adsorption energies were calculated, and electronic properties like charge density and Mulliken charge transfer were analyzed. All simulations used the CASTEP module in Materials Studio.

The structural, electronic, and magnetic properties of the KCrF3 perovskite have been investigated using an all-electron Gaussian-type basis set and various functionals, including full-range and range-separated hybrids, as implemented in the crystal code. Structural optimizations were performed by imposing tetragonal (I4/mcm) and monoclinic (I112/m) space-group symmetries, corresponding to the experimentally observed phases above and below 250 K, respectively. Three AFM arrangements were considered and compared with the FM one: the AFMA phase (spin inversion between first-neighbor Cr ions along the c-axis) is more stable than the FM phase, in agreement with experimental evidence. The monoclinic I112/m structure is energetically favored over the tetragonal I4/mcm phase by 5.9 meV per transition-metal ion with the B3LYP functional, and by 3.4 meV when using PBE0 or HSE06. This small energy difference is associated with only minor changes in structural and electronic properties, including a slight volume contraction (-0.4%) and increase in the band gap (+2%). Mulliken population analysis indicates a Cr d-shell occupation of 3.907 |e|, which is very close to the formal d4 configuration. Nearly exactly three electrons populate the t2g manifold (0.974 |e| each), while the remaining electron is distributed between the (0.360 |e|) and (0.624 |e|) orbitals. Spin-density maps clearly show the orbital ordering within the ab plane and provide insight into the stabilization mechanism of the AFMA phase, which is mediated by the polarization of the fluorine valence shell.

The structural, vibrational, and electronic properties of 2-methyl-5-nitro-1H-benzimidazole-6-amine (MNBA) were analyzed using experimental and theoretical approaches. Density Functional Theory (DFT) simulations utilizing the B3LYP functional and 6-311++G(d,p) basis set were performed to optimize the geometry, predict vibrational frequencies, and analyze the frontier molecular orbitals (HOMO-LUMO) of the MNBA molecule. FT-IR and UV-Vis spectroscopy were used to empirically validate the results, which were subsequently compared to theoretical predictions in both gaseous and aqueous phases. The study highlights the critical role of intramolecular hydrogen bonding between the nitro and amine groups, which forms an intramolecular O···H interaction, that may contribute to the stabilization of the molecular structure. Solvent effects substantially affected molecular shape and electronic distribution, with aqueous phase calculations showing improved concordance with experimental results. Mulliken charge analysis together with molecular electrostatic potential (MEP) mapping provides qualitative insight into the charge distribution and possible reactive regions of MNBA. A reduced HOMO–LUMO gap in aqueous solution suggests enhanced electronic reactivity of the molecule in polar environments, providing insight into the structural and electronic characteristics of MNBA. This study demonstrates the effective integration of DFT simulations and experimental methodologies to elucidate the physicochemical properties of benzimidazole derivatives under diverse environmental conditions.

Density-functional tight binding (DFTB) enables efficient simulations for large molecular systems, but atomic charges are typically reported via Mulliken population analysis and often deviate from density-based charge definitions at the density functional theory (DFT) level. Minimal basis iterative stockholder (MBIS) charges are attractive due to numerical stability and reduced basis-set sensitivity, yet MBIS is not available in standard DFTB workflows due to the lack of a real-space electron density. Here we develop a minimal machine-learning (ML) correction that maps DFTB Mulliken charges to MBIS charges at the atom-wise level. The model uses only atomic identities, Mulliken charges, and local-geometry descriptors, while enforcing exact molecular charge conservation by a per-molecule shift. Using 5000 molecules from the QM9 dataset (4000/500/500 for training/validation/testing), we show that nonlinearity alone provides limited improvement over an element-wise linear baseline, whereas incorporating local geometric descriptors yields substantial accuracy gains, particularly for carbon and nitrogen. The proposed correction provides DFT-level charge quality at a computational cost comparable to standard DFTB calculations and can be integrated into existing workflows. The ML correction is applied strictly as a non-variational post-processing step after SCC convergence and does not modify the underlying DFTB Hamiltonian, total energy, or analytical gradients.

This study explores the combinatorial potential of carvacrol-lawsone adduct (CALA) by analyzing its structural, electronic, and binding features against breast cancer-associated targets. Density functional theory (DFT) calculations optimized the CALA structure, revealing band gap energies of 2.036eV (without GD3) and 1.917eV (with GD3), suggesting favorable electronic reactivity. Molecular electrostatic potential mapping highlighted regions of charge depolarization, while Mulliken and Natural Population Analyses provided insights into atomic charge distribution. The electronic topology was further characterized using the electron localization function (ELF) and localized orbital locator (LOL), whereas reduced density gradient (RDG) and non-covalent interaction (NCI) analyses clarified intermolecular interactions. Pharmacokinetic predictions indicated drug-like properties, and molecular docking revealed strong affinity of CALA toward AKT1 with a binding energy of -11.4kcal/mol. Molecular dynamics simulations supported the stability of the CALA+AKT1 complex, showing consistent root mean square deviation (RMSD) values (2.5-3.0 Å) and root mean square fluctuation (RMSF) below 3.0 Å. Collectively, CALA demonstrates favorable reactivity, structural stability, pharmacological potential, and strong AKT1 interaction. These findings propose CALA as a promising combinatorial candidate for targeting AKT1 to inhibit breast cancer progression, although further in vitro and in vivo validation is necessary to establish its therapeutic applicability.

ABSTRACT Diabetes mellitus (DM) is a chronic metabolic disorder characterized by persistent hyperglycemia, primarily due to imbalance in insulin secretion or action, resulting in inadequate carbohydrate and lipid metabolism. In this study, carbothioamide derivatives (C1–C3) were synthesized and assessed for their antidiabetic potential through α‐glucosidase inhibition in vitro and in vivo studies. The in vitro assay revealed good α‐glucosidase inhibition, with IC 50 values of 560, 101, and 330 (µg/mL) for C1 , C2 , and C3 , respectively, compared to standard acarbose (IC 50 = 36 µg/mL). Molecular docking, DFT calculations, in silico ADMET analyses, and Mulliken charge distribution supported promising binding interactions of the compounds with key residues of α‐glucosidase (PDB ID: 5ZCC), besides with acceptable drug‐likeness, high projected gastrointestinal absorption, and no blood–brain barrier permeation. Following confirmation of in vitro activity, the derivatives were evaluated for acute toxicity and in vivo antidiabetic efficacy in alloxan‐induced diabetic mice. None of the compounds revealed toxicity up to 200 mg/kg. Compounds C1–C3 , administered at 2.5 and 5 mg/kg, considerably ( p < 0.001) reduced blood glucose levels without inducing hypoglycemia when matched compared with glibenclamide (0.5 mg/kg), and also improved body weight in diabetic mice. Among them, C2 exhibited the most promising antidiabetic activity across in vitro and in vivo models.

Crystal growth, structural scrutiny, optical properties, Hirshfeld surface examination and DFT calculations of an organic NLO material −2,4,6-trinitrophenyl benzoate

Rhombohedral Na₀.₅Bi₀.₅TiO₃ (NBT) is a representative lead-free ferroelectric, yet a unified microscopic understanding linking bonding, electronic structure, and optical response remains incomplete. In this work, first-principles density functional theory calculations are performed to systematically investigate the structural, electronic, magnetic, and optical properties of pristine rhombohedral NBT. The optimized R3c structure is energetically stable and consistent with experimental data. Electronic structure analysis shows that NBT is a direct band-gap semiconductor with a calculated gap of ~2.86 eV, where the valence band is dominated by O-2p states and the conduction band mainly originates from Ti-3d states with minor Bi-6p contributions. Mulliken population analysis reveals a mixed ionic–covalent bonding nature, with pronounced Ti–O covalency. Importantly, a clear correlation between Ti–O covalent interactions, conduction-band formation, and dominant ultraviolet optical transitions is established, providing a quantitative microscopic interpretation beyond previous qualitative studies. Spin-polarized calculations confirm an intrinsically non-magnetic ground state. These results offer a reliable theoretical reference for NBT-based functional materials.

Abstract: Curcumin, a naturally occurring polyphenol abundant in Curcuma species of the Zingiberaceae family, exhibits diverse pharmacological activities, including antioxidant and antitumor effects. In this study, density functional theory (DFT) was employed to comprehensively investigate the reactive sites of curcumin using multiple theoretical approaches, including frontier molecular orbital analysis, Mulliken charges, electrostatic potential (ESP) distribution, dipole moment, interaction region indicator (IRI), van der Waals potential, and bond order. This work not only provides a molecular- level theoretical foundation for understanding the chemical reactivity and pharmacological mechanisms of curcumin, which is crucial for elucidating its pharmacological mechanisms. The identified reactive sites offer valuable insights for the rational design of curcumin-based derivatives with improved solubility and targeted bioactivity. materials and methods: In this study, density functional theory (DFT) was employed to comprehensively investigate the reactive sites of curcumin using multiple theoretical approaches, including frontier molecular orbital analysis, Mulliken charges, electrostatic potential (ESP) distribution, dipole moment, interaction region indicator (IRI), van der Waals potential, and bond order. results: We successfully employed DFT to comprehensively analyze the molecular properties and reactive sites of curcumin. The results demonstrate that the curcumin molecule contains various functional groups (which form an extended conjugated system), adopts a non-planar conformation due to steric repulsion, and that the conjugation induces electron delocalization—an effect that significantly influences the molecule’s electronic properties and reactivity. Analyses of HOMO/LUMO, Mulliken atomic charges, and ESP distribution collectively identified oxygen atoms (particularly O1 and O5) as the primary sites for electrophilic attack, while positively charged carbon (e.g., C13) and hydrogen atoms (e.g., H41) were determined to be the main nucleophilic reaction sites. The presence of an intramolecular hydrogen bond, as revealed by the IRI, further enhances the electrophilic potential of O1. In the van der Waals potential profile of curcumin, repulsive potentials are predominantly distributed over the left benzene ring and the central carbon chain region, which helps prevent random molecular aggregation and ensures the exposure of active sites. Attractive potentials are localized in small regions such as O1, facilitating interactions with other molecules and promoting electrophilic reactions. discussion: This work not only provides a molecular-level theoretical foundation for understanding the chemical reactivity and pharmacological mechanisms of curcumin, but also offers valuable insights for the development of curcumin-based derivatives. conclusion: These findings provide theoretical insights into curcumin’s pharmacological mechanisms and guide future structural modifications to enhance its bioactivity.