Electron Localization Research Articles

Spectroscopically Elucidating the Local Proton-Coupled Electron Transfer Loop from Amino to Nitro Groups via the Au Surface in a N2 Atmosphere

Spectroscopically Elucidating the Local Proton-Coupled Electron Transfer Loop from Amino to Nitro Groups via the Au Surface in a N₂ Atmosphere

Controlling the Polarity of Metal–Organic Frameworks to Promote Electrochemical CO2 Reduction

AbstractThe addition of polar functional groups to porous structures is an effective strategy for increasing the ability of metal–organic frameworks (MOFs) to capture CO2 by enhancing interactions between the dipoles of the polar functional groups and the quadrupoles of CO2. However, the potential of MOFs with polar functional groups to activate CO2 has not been investigated in the context of CO2 electrolysis. In this study, we report a mixed‐ligand strategy to incorporate various functional groups in the MOFs. We found that substituents with strong polarity led to increased catalytic performance of electrochemical CO2 reduction for these polarized MOFs. Both experimental and theoretical evidence indicates that the presence of polar functional groups induces a charge redistribution in the micropores of MOFs. We have shown that higher electron densities of sp2‐carbon atoms in benzimidazolate ligands reduces the energy barrier to generate *COOH, which is simultaneously controlled by the mass transfer of CO2. Our research offers an effective method of disrupting local electron neutrality in the pores of electrocatalysts/supports to activate CO2 under electrochemical conditions.

Visible‐Light‐Induced Rapid Elimination of Antibiotic Resistance Contaminations Using Graphitic Carbon Nitride Tailored with Carrier Confinement Domains

AbstractSolar water disinfection facilitated by photocatalyst has been considered a viable point‐of‐use (POU) method for mitigating antibiotic resistance contaminations at the household or community levels. Here, density functional theory calculations are used to guide the fabrication of a carrier confinement domains (CCD)‐decorated graphitic carbon nitride (CN) photocatalyst. The CCD integration effectively disrupts the electron distribution symmetry of CN, amplifies its local electron density, and facilitates the formation of long‐range ordered structure, thereby enhancing charge separation efficiency. Importantly, the CCD directs the migration of photogenerated carriers to specific regions upon light illumination, effectively minimizing their spatial proximity. As a result, the overall reactive oxygen species level of the photocatalytic system is markedly elevated, with a twelvefold increase in H2O2 concentration, alongside a nearly two‐order‐of‐magnitude rise in •O2− and •OH steady‐state concentrations. Remarkably, a record‐high disinfection efficiency is attained, successfully inactivating 7 log of antibiotic‐resistant bacteria within 30 min. Additionally, the photocatalyst can be integrated into a continuous‐flow fixed‐bed reactor, facilitating clean water production for up to 60 h at a rate of 121 L m−2 day−1, highlighting its significant potential for POU applications.

Fenton-Inactive Cd Enables Highly Selective O2-Derived Domino Reaction.

Advancing and deploying Fenton-inactive Cd that combines excellent catalytic activity, selectivity, and stability remains a serious challenge, predominantly owing to the difficulty in regulating the intrinsic electronic states and local geometric structures of such fully occupied d10s2 configuration. In this work, a combination of experiments and theoretical calculations reveals that the incorporation of boron (B) enables the tuning of the average oxidation state of Cd0 to Cdδ+, facilitating electron localization and implementing a different electrocatalytic preference compared to conventional d10-electron configurations. The resulting Cd(B) catalyst demonstrates high selectivity (>90% on average) in the O2-to-H2O2 conversion, negligible activity loss over 100h, and a superior H2O2 production rate (15.5mol∙gcat -1h-1 at -100mA). More unexpectedly, the in situ generated H2O2 exhibits a unique advantage over commercial products, selectively oxidizing cinnamaldehyde to benzaldehyde by modulating the practical current.

Copper diffusion hindrance in Ti-TM (TM = W, Ru) alloys: A first-principles insight

This study utilizes DFT calculations to assess the effectiveness of Ti-TM (TM = W, Ru) alloys in obstructing copper diffusion, a pivotal factor for semiconductor device reliability. The calculated diffusion barriers for Cu in TiRu and Ti4W12 alloys are found to be 0.48 eV and 0.34 eV, respectively, significantly surpassing the 0.25 eV barrier for Cu diffusion in Si. This comparative analysis highlights the enhanced diffusion resistance of these alloys, with TiRu displaying a barrier nearly twice that of Si. An in-depth examination of the electronic structure and microstructural attributes of the alloys indicates that atomic interactions at the Cu/Ti-TM interface play a crucial role in hindering Cu diffusion. The local density of states, charge density differences, and electron localization functions were scrutinized to clarify the nature of these interactions. The research uncovers that the combined action of Ru, W, Cu, and Ti atoms leads to a synergistic strengthening of the diffusion barrier, implying a robust interatomic repulsion that restricts Cu migration. The findings contribute to a deeper fundamental understanding of Cu diffusion mechanisms in Ti-TM alloys and offer a scientific basis for the judicious selection of materials for diffusion barrier layers. The study supports the further exploration and potential application of TiRu and Ti4W12 alloys in the semiconductor industry.

Cs3LiGe4, One Compound with Two Complementary Structural Descriptions: Isolated [Ge4]4- Tetrahedral Clusters Coordinated by Li+ and Cs+ Cations or One-Dimensional [LiGe4]3- Polyanions Packed within a Matrix of Cs+ Cations?

Reported are the synthesis and structural characterization of Cs3LiGe4, the first structurally characterized lithium-containing cesium germanide. Single-crystal X-ray diffraction data indicate that Cs3LiGe4 crystallizes in an orthorhombic crystal system with the space group Cmcm (no. 63, Person symbol oS32) with unit cell parameters a = 6.950(2) Å, b = 15.503(3) Å, and c = 9.919(2) Å and V = 1068.65(4) Å3. The structure consists of [Ge]44- tetrahedral clusters with the Li atoms positioned in such a way that polyanionic [LiGe]43- chains could be considered as well. Electronic structure calculations indicate an intrinsic semiconductor with a band gap of 0.76 eV. To understand the nuances of the chemical bonding, position-space techniques based on the quantum theory of atoms in molecules, the electron localizability indicator, and their basin intersections were employed confirming the covalent character of the Ge-Ge bonding. The strong polarity of the interactions between [Ge]44- and the surrounding lithium and cesium cations suggests to interpret these as mainly ionic, further supporting the most basic structure rationalization [Cs+]3[Li+][Ge]44-, following the Zintl-Klemm concept. The electron localizability indicator topology affirms the striking similarities between [Ge]44- and molecular As4 tetrahedra in yellow arsenic, further supporting Klemm's pseudoatom concept on a quantum chemical basis.

A Comprehensive Journey of a Vanillic Aldehyde-Chloroaniline Schiff Base from Solvent-Free Synthesis to Electronic Structure, In Silico and In Vitro Biological Analysis

Schiff bases possess a range of unique physical, chemical and medicinal properties, which contribute to their potency as biological agents. A Schiff base was synthesized, which consisted of 4-chloro aniline and vanillin. The successful formation of the compound was confirmed by their comparable FTIR, UV–Vis, 1HNMR and [Formula: see text]CNMR spectra. The compound was analyzed using X-ray crystallography, which revealed that it crystallizes in the monoclinic system with the space group P21/c. The Hirshfeld surface analysis revealed valuable information about the intermolecular interactions present in the crystal lattice. The most common contacts observed were between hydrogen and hydrogen, as well as carbon and hydrogen. The obtained fluorescence values of 375 nm and 412 nm at excitation wavelength 322 nm strongly indicated the luminescent nature of the compound. The thermal stability of the compound was assessed through thermogravimetric analysis (TGA). DFT was used to optimize the geometry using the B3LYP/cc-pVDZ basis set. The compound exhibited an energy gap of 2.35 electron volts (eV). According to the analysis of molecular electrostatic potential, C and O atoms were found to be electrophilic. According to Mulliken charge analysis, C atoms possess both positive and negative charges, hydrogen atoms exclusively carry positive charges, and Cl, O and N atoms exclusively carry negative charges. Upon analysis of the molecule, the electron localization function discovered that the atoms of carbon, nitrogen and chlorine exhibited delocalized electron density. Also, the localized orbital locator identified the localized orbital positions in the hydrogen atoms. The reduced density gradient (RDG) maps exhibit a wide range of noncovalent interactions. In comparison to the standard amoxicillin, the synthesized compound demonstrated moderate antimicrobial efficacy against the gram-positive bacteria Klebsiella pneumoniae and the fungi Candida albicans. The compound’s concentration-dependent antioxidant and anti-inflammatory properties were demonstrated through in vitro biological evaluation using 2,2-diphenyl-1-picrylhydrazyl and human red blood cell (HRBC) methods. The compound was docked using the proteins 7BYE and 4LEB were chosen from both organisms. The lowest binding attractions obtained were -3.40 kcal/mol for 7BYE and -4.51 kcal/mol for 4LEB. To investigate the stability of the protein–ligand complex, molecular dynamic simulation was employed. The ligands in silico toxicity potentialities were analyzed using seven toxicity models and the results indicated that the ligand is biocompatible.

Morphofunctional Features of Glomeruli and Nephrons After Exposure to Electrons at Different Doses: Oxidative Stress, Inflammation, Apoptosis

Kidney disease has emerged as a significant global health issue, projected to become the fifth-leading cause of years of life lost by 2040. The kidneys, being highly radiosensitive, are vulnerable to damage from various forms of radiation, including gamma (γ) and X-rays. However, the effects of electron radiation on renal tissues remain poorly understood. Given the localized energy deposition of electron beams, this study seeks to investigate the dose-dependent morphological and molecular changes in the kidneys following electron irradiation, aiming to address the gap in knowledge regarding its impact on renal structures. The primary aim of this study is to conduct a detailed morphological and molecular analysis of the kidneys following localized electron irradiation at different doses, to better understand the dose-dependent effects on renal tissue structure and function in an experimental model. Male Wistar rats (n = 75) were divided into five groups, including a control group and four experimental groups receiving 2, 4, 6, or 8 Gray (Gy) of localized electron irradiation to the kidneys. Biochemical markers of inflammation (interleukin-1 beta [IL-1β], interleukin-6 [IL-6], interleukin-10 [IL-10], tumor necrosis factor-alpha [TNF-α]) and oxidative stress (malondialdehyde [MDA], superoxide dismutase [SOD], glutathione [GSH]) were measured, and morphological changes were assessed using histological and immunohistochemical techniques (TUNEL assay, caspase-3). The study revealed a significant dose-dependent increase in oxidative stress, inflammation, and renal tissue damage. Higher doses of irradiation resulted in increased apoptosis, early stages of fibrosis (at high doses), and morphological changes in renal tissue. This study highlights the dose-dependent effects of electrons on renal structures, emphasizing the need for careful consideration of the dosage in clinical use to minimize adverse effects on renal function.

Metal-Metal Bonding in Tri-Actinide Clusters: A DFT Study of [An3Cl6] z (z = 1-6) and [An3Cl6Cp3] z (z = -2- +3; An = Ac, Th, Pa, U, Np, Pu).

The actinide-actinide bonding in tri-actinide clusters [An₃Cl₆]ᶻ (An = Ac-Pu, z = 1-6) and [An₃Cl₆Cp₃]ᶻ (z =-2-+3; Cp = (η5-C5H5)) is studied using density functional theory. We find 3-centre bonding similar to the tri-thorium cluster [{Th(η⁸-C₈H₈)(μ₃-Cl)₂}₃{K(THF)₂}₂]∞, as we previously reported (Nature 2021, 598, 72-75). The population of 3-centre molecular orbitals (3c-MOs) by zero, one or two electrons correlates with shortening of the An-An bond lengths, which also decrease with increasing actinide atomic number, consistent with the contraction of the actinide valence atomic orbitals. Mulliken analyses indicate that these 3c-MOs predominantly involve An 6d and 5f orbitals. Various methods evidence the presence of An-An bonding in most systems with populated 3c-MOs, including bond orders (Mayer and Wiberg), quantum theory of atoms in molecules metrics (ρ, ∇²ρ, -G/V, H, delocalization indices), electron localization function, and electron density assessments. Additionally, we explore the effect of Cp ligand substitution on uranium complexes, finding that bulkier Cp ligands can induce U-U bond distortions and result in slightly longer U-U bonds. Overall, this study advances our understanding of metal-metal bonding in tri-actinide clusters, highlighting its effects on geometric and electronic structures.

Quasicrystalline 30° twisted bilayer graphene: fractal patterns and electronic localization properties

The recently synthesized 30° twisted bilayer graphene (30°-TBG) systems are unique quasicrystal systems possessing dodecagonal symmetry with graphene’s relativistic properties. We employ a real-space numerical atomistic framework that respects both the dodecagonal rotational symmetry and the massless Dirac nature of the electrons to describe the local density of states of the system. The approach we employ is very efficiency for systems with very large unit cells and does not rely on periodic boundary conditions. These features allow us to address a broad class of multilayer two-dimensional crystal with incommensurate configurations, particularly TBGs. Our results reveal that the 30°-TBG electronic spectrum consist of extended states together with a set of localized wave functions. The localized states exhibit fractal patterns consistent with the quasicrystal tiling.

ASSESSMENT OF THE INFLAMMATORY RESPONSE IN THE PANCREAS AFTER ADMINISTRATION OF N-ACETYL CYSTEINE IN A MODEL OF POST-RADIATION PANCREATITIS

Introduction. Ionizing radiation can lead to radiation damage to healthy pancreatic tissue, with the development of signs of post-radiation pancreatitis. Electron irradiation potentially has the most “sparing” effect on healthy tissue, but data on this are sparse. The search for means to protect healthy tissues from the effects of ionizing radiation remains relevant. Thus, the use of agents with antioxidant properties (N-acetylcysteine) can potentially slow down the development of post-radiation pancreatitis. The aim of the study: assessment of the inflammatory response in the pancreas after administration of N-acetylcysteine in a radiation-induced pancreatitis model. Methods. Wistar rats (n=120) were divided into four groups: I (n=30) – control; II (n=30) – irradiation with electrons in a total irradiation dose of 25 Gy; III (n=30) – pre-irradiation administration of N-acetylcysteine before electron irradiation; IV (n=30) – administration of N-acetylcysteine. Animals were removed from the experiment on the 7th, 30th and 90th days. A morphological assessment of pancreatic fragments and an immunohistochemical study with antibodies to pro- (IL-1, IL-6) and anti-inflammatory (IL-10) cytokines, markers of T-lymphocytes (CD3) and macrophages (CD68) were carried out. Results. At all stages of the experiment, high levels of expression of pro- and anti-inflammatory cytokines were observed in the electron irradiation group with a slight increase in the number of CD3+ T-lymphocytes and CD68+ macrophages. In the group of pre-radiation administration of N-acetylcysteine, increased levels of immunolabeling were also found when conducting reactions with antibodies to pro- and anti-inflammatory cytokines, however, by the third month of the experiment, practically no CD3+ and CD68+ immunocompetent cells were noted in this group. Conclusion. Pancreatic local electron irradiation at a total dose of 25 Gy in the early stages leads to the development of a stromal-vascular inflammatory reaction with a capillary-parenchymal block with practically no cellular inflammatory infiltration. At the same time, pre-radiation administration of N-acetylcysteine partially prevents the development of post-radiation pancreatitis.

Designing multicomponent hydrides with potential high Tc superconductivity

While hydrogen-rich materials have been demonstrated to exhibit high Tc superconductivity at high pressures, there is an ongoing search for ternary, quaternary, and more chemically complex hydrides that achieve such high critical temperatures at much lower pressures. First-principles searches are impeded by the computational complexity of solving the Eliashberg equations for large, complex crystal structures. Here, we adopt a simplified approach using electronic indicators previously established to be correlated with superconductivity in hydrides. This is used to study complex hydride structures, which are predicted to exhibit promisingly high critical temperatures for superconductivity. In particular, we propose three classes of hydrides inspired by the Fm[Formula: see text]m RH[Formula: see text] structures that exhibit strong hydrogen network connectivity, as defined through the electron localization function. The first class [RH[Formula: see text]X[Formula: see text]Y] is based on a Pm[Formula: see text]m structure showing moderately high Tc, where the Tc estimate from electronic properties is compared with direct Eliashberg calculations and found to be surprisingly accurate. The second class of structures [(RH[Formula: see text])[Formula: see text]X[Formula: see text]YZ] improves on this with promisingly high density of states with dominant hydrogen character at the Fermi energy, typically enhancing Tc. The third class [(R[Formula: see text]H[Formula: see text])(R[Formula: see text]H[Formula: see text])X[Formula: see text]YZ] improves the strong hydrogen network connectivity by introducing anisotropy in the hydrogen network through a specific doping pattern. These design principles and associated model structures provide flexibility to optimize both Tc and the structural stability of complex hydrides.

Computational Investigation and Antimicrobial Activity Prediction of Potential Antiviral Drug

The ethyl 2-amino-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carboxylate (S1) was chosen for this investigation due to its important biological and pharmacological activities. Detailed infrared and Raman spectra have been investigated in both theoretical and experimental. Frontier molecular orbitals and the electronic properties of the S1 are explained. The titled compound S1 calculated HOMO-LUMO energy gap is 4.60 eV. In molecular electrostatic potential (MEP) map the NO2 group exhibits a blue color, indicating the presence of nucleophilic sites. The density of state (DOS), non-covalent interaction (NCI), electron localized function (ELF), localized orbital locator (LOL), Mulliken atomic charges, and reactive sites have been investigated. The anti-bacterial, antifungal, antitoxin, antiviral, and antimycobacterial studies have been investigated. The molecular docking investigations of the compound were also conducted. Using the Auto-dock program, the compound S1 molecular docking study has been conducted. The molecular docking study's lowest binding energy is -7.91, -5.62, -6.92, and -5.85 kcal/mol for 4XGK, 4ATO, 3U9G, and 2DP4 respectively.

Electronic, thermodynamic, NLO, and spectroscopic properties of OAFLC compounds via DFT: A focus on 1F6B, 1F6Bi, 1F6BiN, and 1F6BN

This study presents a comprehensive quantum mechanical investigation of four novel liquid crystalline compounds: 1F6B, 1F6Bi, 1F6BiN, and 1F6BN. Using Density Functional Theory (DFT) with the B3LYP functional and 6-311G(d,p) basis set, we optimized the molecular geometries and analyzed their electronic and vibrational properties. Atomic Polar Tensor (APT) charge analysis showed significant charge distributions. Electrostatic potential (ESP) mapping identified potential reactive sites, while Electron Localization Function (ELF) and Localized Orbital Locator (LOL) analyses depicted the electron density distributions. Thermodynamic parameters indicated the compounds’ vibrational stability and responsiveness to thermal changes. Non-linear optical (NLO) properties were characterized by significant dipole moments and polarizabilities, suggesting potential in optoelectronic applications. Frontier molecular orbital analysis indicated stability with HOMO-LUMO gaps ranging from 4.15 to 4.64 eV. UV–Vis spectra revealed key electronic transitions, while Raman spectroscopy detailed various vibrational modes. The study offers valuable insights into the molecular behavior of these compounds, laying the groundwork for their future applications in material science and advanced technologies.

Synthesis, Theoretical Gaussian Quantum Chemical Calculations, and Spectroscopic Elucidation of N‐(4‐bromophenyl)‐10H‐phenothiazine‐10‐carboxamide

AbstractPhenothiazine derivative N‐(4‐bromophenyl)‐10H‐phenothiazine‐10‐carboxamide (BPC), a novel compound is selected for the present study based on the reported effectiveness of phenothiazine towards neurodegenerative diseases. Synthesis and characterization of BPC are carried out in the present work. To comprehend the electronic and structural aspects of BPC, quantum chemical studies are performed. Computational aspects using the density functional theory method using B3LYP/6–31 G ++(d,p) as a basis set are studied for the geometry optimization of the molecule. To analyze the reactivity, stability, and intramolecular interactions of the compound frontier orbital molecular analysis, molecular electrostatic potential distribution, and Fukui function are implemented. Calculations have been made to determine the electrophilic and nucleophilic descriptors of the title compounds by Fukui function evaluations on atomic charges. To visualize and quantify the localization of electrons and molecular orbitals in the molecule, electron localization function, localized orbital locator analysis and orbital localization analysis are carried out for a better understanding of chemical bonding. Basin Analysis is used for analysis of the nature of chemical bonds and interactions. To understand bond strengths, hyperconjugation, and reactivity natural bond orbital analysis is performed.

Ag Atom Induces Microstrain Environment around Cd Sites to Construct Diatomic Sites for Almost 100% CO2-to-CO Electroreduction.

Deeply understanding how local microstrain environment around diatomic sites influences their electronic state and adsorption is crucial for improving electrochemical CO2 reduction (eCO2R) reaction; however, precise engineering of the atomic microstrain environment is challenging. Herein, we fabricate Ag-CdTMT electrocatalysts with AgN2S2-CdN2S2 diatomic sites by anchoring Ag to the nodes of CdTMT (TMT = 2,4,6-trimercaptotriazine anion) coordination polymers. The Ag-CdTMT catalysts achieve approximately 100% Faradaic efficiency for CO reduction with an industrial level current density (∼200 mA cm-2 in H-cell). The embedded Ag atoms induce the formation of Ag-Cd diatomic sites with local microstrain, stretching Cd-N/S bonds, and reinforcing electron localization at Cd sites. The microstrain engineering and adjacent Ag atoms synergistically reduced Cd 4d-C 2p antibonding orbital occupancy for intensifying *COOH adsorption as the rate-determining step. This study provides novel insights into customizing the electronic structure of diatomic sites through strain engineering.

First-principles calculations of orthorhombic chalcogenide ABX3 (A = Ca, Sr, Ba; B = Ge, Sn; X = O, S, Se, Te) perovskites by cation and anion variation

The first-principles calculations are used to investigate on the structural, electronic, optical properties of orthorhombic chalcogenide ABX3 (A = Ca, Sr, Ba; B = Ge, Sn; X = O, S, Se, Te) perovskites. All cation and anion variations will only change the lattice parameters, but the orthorhombic crystal structures maintain stability apart from CaGeS3. The electron density difference demonstrates the differences in interaction strength and degree of electron localization to some extent in various systems. The sulfide perovskites are all semiconductors with bandgaps between 1 - 3 eV while the variable anions can realize the transition from the insulator (5.263 eV) to narrow semiconductors (0.134 eV). Besides, the photoresponse can be modulated to a better match with solar irradiance by anion variation. Among all studied SrSnX3 (X = O, S, Se and Te) materials, SrSnSe3 has the best performance as a solar absorber due to its best light absorption and proper bandgap value (∼1.6 eV).

Modulating the local electron density at built-in interface iron single sites in Fe-CN/MoO3 heterostructure for enhanced CO2 reduction to CH4 and Photo-Fenton reaction

The catalytic efficiency of heterogeneous photocatalytic CO2 reduction and photo-Fenton H2O2 activationisclosely related to the local electron density of reaction center atoms. However, electron-hole recombination from random charge transfer significantly restricts the targeted electron delivery to the active center. Herein, Fe-C3N4/MoO3 heterojunction with interfacial coordination of atomically dispersed Fe-N4 sites with the O interface of MoO3 was synthesized by simple hydrothermal method. Based on the experimental results and density functional theory calculation (DFT), the heterojunction structure fosters accelerated interfacial electron transfer due to directional interfacial electric field (IEF) between Fe-CN and MoO heterogeneous interfaces, and the interfacial bond between Fe-N4 sites and O at the built-in interface regulates the local electron density of Fe-N4 active center. DFT further reveals that the interfacial electron flow and concentrated electron density at Fe-N4 sites result from the coordination between Fe-N4 and MoO3 interfaces. This directs electron flow towards the Fe center, significantly enhancing CO2 adsorption and H2O2 conversion efficiency. PDOS analysis shows that the dyz and dz2 orbitals of the isolated Fe atom in Fe-CN overlap with the pz orbital of the O atom in MoO3, playing a pivotal role in CO2 adsorption. Consequently, the Fe-CN/MoO3 heterojunction demonstrated highly efficient photocatalytic CO2 reduction to CH4, coupled with benzyl alcohol oxidation and photo-Fenton tetracycline degradation. These findings offer a promising multifunctional catalyst strategy for the development of energy conversion and environmental remediation.

Correlations between local chemical fluctuations and grain boundary strength in Ti-Zr-Nb-Ta-Mo refractory multi-principal element alloys

Ti-Zr-Nb-Ta-Mo refractory multi-principal element alloys typically exhibit high yield strength while tensile ductility tends to be poor. In this study, we found that even after solid solution treatment of Ti-Zr-Nb-Ta-Mo alloys, significant change in ductility occur due to the local chemical fluctuations. Ta's dramatic chemical fluctuations cause variations in atomic-scale strain fields, leading to reduced grain boundary strength and brittle fracture. First-principles calculations show that (Ti, Zr)-rich at the grain boundaries increases the delocalization of valence electrons, leading to longer bond lengths and reduced crystal orbital bond index values, thereby causing grain boundary embrittlement. Our findings explore the root causes of brittleness in Ti-Zr-Nb-Ta-Mo alloys at the atomic and electronic scales, providing not only a method to analyze grain boundary embrittlement using bond length, electronic localization function and crystal orbital bond index, but also a theoretical guidance for improving the mechanical properties via grain boundary structure optimization.

Experimental Realization of Fluoroborophene.

Borophene, an anisotropic metallic Dirac material exhibits superlative physical and chemical properties. While the lack of bandgap restricts its electronic chip applications, insufficient charge carrier density and electrochemical/catalytically active sites, restricts its energy storage and catalysis applications. Fluorination of borophene can induce bandgap and yield local electron injection within its crystallographic lattice. Herein, a facile synthesis of fluoroborophene with tunable fluorine content through potassium fluoride-assisted solvothermal-sonochemical combinatorial approach is reported. Fluoroborophene monolayers with lateral dimension 50 nm-5 µm are synthesized having controlled fluorine content (12-35%). Fluoroborophene exhibits inter-twinned crystallographic structure, with fluorination-tunable visible-range bandgap ≈1.5-2.5 eV, and density functional theory calculations also corroborate it. Fluoroborophene is explored for electrocatalytic oxygen evolution reaction in an alkaline medium and bestow a good stability. Tunable bandgap, electrophilicity and molecular anchoring capability of fluoroborophene will open opportunities for novel electronic/optoelectronic/spintronic chips, energy storage devices, and in numerous catalytic applications.