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DFT is used for making first-principles calculations of electronic and optical properties of V₂O₅ in its orthorhombic phase, by employing Augmented Plane Waves$+$local orbital method with Generalized Gradient Approximation and Perdew–Burke–Ernzerhof potential to account for exchange–correlation interactions. The stability of the material is checked through the calculation of cohesive energy and Bader charge analysis is done to find out the electronic charges on different atoms in the unit cell. A DOS gap of about 2.1eV and a direct band gap of about 1.85eV just above the Fermi level is found to occur on using DFT, which is lower than the experimental value of 2.77eV. On using the DFT$+$U method, with $U=4.0$eV for Vanadium, a DOS gap of about 2.8eV and an indirect band gap of about 3.0eV are found to occur, which are closer to the experimental result, showing that the DFT+U method better accounts for electronic properties of V₂O₅. The optical properties, such as dielectric function, reflectivity, absorption coefficient, optical conductivity, refractive index, extinction coefficient and electron energy loss function also investigated for V₂O₅ by using DFT.

In this work, we delve into the investigation of the structural, electronic, and optical properties of Ba₂NbBiS₆ and Ba₂TaSbS₆ chalcogenide-based double perovskites, which are structured in the cubic space group $Fm\bar{3}m$ form. We have performed first-principles calculations using density functional theory (DFT) to study the above properties. The electronic band structure and density of states of this compound have been investigated, and their results show that Ba₂NbBiS₆ and Ba₂TaSbS₆ exhibit a semiconducting nature with an indirect energy gap of 1.680eV and 1.529eV, respectively. Furthermore, an investigation was conducted on the optical properties of the compounds throughout the energy range spanning from 0eV to 55eV. This investigation focused on many parameters, including dielectric functions, optical reflectivity, refractive index, extinction coefficient, optical conductivity, and electron energy loss. The optical data obtained from the calculations reveals that all compounds demonstrate isotropy in optical polarization. Furthermore, it has been noted that our compounds exhibit absorption properties inside the ultraviolet (UV) region. Consequently, these materials hold promise as potential candidates for various applications, such as UV photodetectors, UV light emitters, and power electronics. This is primarily attributed to their inherent absorption limits and the presence of prominent absorption peaks in this spectral range. In brief, chemical mutation techniques have been employed to manipulate the characteristics of double-sulfide perovskites to develop durable and environmentally friendly perovskite materials suitable for solar purposes.

This study provides a thorough analysis of magnesium oxynitride (MgON), employing first-principles calculations to investigate its potential for electronic, thermoelectric, and optical applications. The main objective was to comprehend the fundamental electronic, thermoelectric, and optical parameters of MgON using density functional theory (DFT) calculations. In electronic properties, the density of states (DOS) spectra revealed the significant contribution of Mg-s and O-p states for pristine MgO, while N-p states provide the maximum contributions with overlapping at the Fermi level in nitrogen-containing compositions. The band structure depicted a direct nature for undoped and doped MgO, and the bandgap of compositions was observed to decrease with the increment in nitrogen concentration. The thermoelectric properties of pure and N-doped MgO compositions were evaluated, which showed significant variations with an increase in temperature and doping. Furthermore, the optical properties of MgON were inspected and found to enhance optical conductivity, and absorption coefficient, whereas the refractive index and dielectric constant decrease at specific energy regions for elevated dopant content, which suggests its suitability for optoelectronic applications. Overall, this study reveals the versatility of MgON, making it a potential candidate for advanced electronic, thermoelectric, and optical applications.

This paper presents a simulation of the structural and optoelectronic properties of Scandium Arsenide (ScAs) and Aluminum Arsenide (AlAs) compounds. Theoretical modeling was performed using ab initio first-principles calculations, specifically the density functional theory (DFT), and the Mindlab numerical software. The software used two methods: the full-potential muffin-tin orbital method (FP-LMTO) and the full-potential plane-wave method (FP-LAPW). These two methods are employed to solve the Schrödinger equation. The exchange correlation effects have been computed using two different approximations: the generalized gradient approximation (GGA) and the local density approximation (LDA). Our findings indicate that the zinc blende structure (B3) is the stable phase, while the Wurtzite phase (B4) is metastable for the AlAs compound. On the other hand, the ScAs compound crystallizes in the NaCl phase (B1). The AlAs compounds undergo three phase transitions: $\mathrm{\text{B3}}\to \mathrm{\text{B4}}$, $\mathrm{\text{B3}}\to \mathrm{\text{B2}}$ and $\mathrm{\text{B3}}\to \mathrm{\text{B1}}$. In contrast, ScAs does not undergo any transition. The obtained results for equilibrium energies, lattice parameters and gap energies are in closer agreement with the experimental and theoretical data. The AlAs compound exhibits a semiconducting character, while ScAs exhibits a semi-metallic character. Additionally, the refractive index of these two compounds is similar to that of silicon, which is crucial for their application in photovoltaic cells.

In this paper, we present the implementation of the Density Functional Theory (DFT) method using the Geant4-DNA framework in the Single Instruction Single Data (SISD) mode. Furthermore, this implementation is improved in terms of execution time within the GeantV project with vectorization techniques such as Single Instruction Multiple Data (SIMD). Within this framework, a set of SIMD strategies in molecular calculation algorithms such as one-electron operators, two-electron operator, quadrature grids, and functionals, was implemented using the VecCore library. The applications developed in this work implement two DFT functionals, the Local Density Approximation (LDA) and the General Gradient Approximation (GGA), to approximate the molecular ground-state energies of small molecules and amino acids. To assess the performance of the implementations, a standard test simulation was performed in multiple CPU platforms. The SIMD vectorization strategy significantly accelerates DFT calculations, leading to time ratios ranging from 1.6 to 5.4 in either individual steps or entire implementations when compared with the scalar process within Geant4.

The influence of incorporating iron on the electronic structure, magnetic and optical properties of zigzag (10,0) boron nitride nanotubes (BNNTs) was investigated using first-principles calculations. The structures were incorporated with Fe according to B1$-x$Fe xN at various (x) contents (0.10, 0.20 and 0.30). Our calculations exhibited that adding additional Fe atoms reduced the energy gap of the structure. Incorporating more iron atoms creates additional sharp peaks within Fermi levels that come from the contribution of Fe-3d states. Doping with (Fe) also introduced magnetic moments in the BNNT structure. The optical parameters of the Fe-incorporated boron nitride nanotube are calculated. The real part of the dielectric function of pristine BNNT started to increase up to the middle of the UV region and then rapidly decreased between the wavelength range of 310–390 nm. Also, the pure boron nitride nanotube has no absorption in the visible light range and only detects UV radiation. The optical calculations showed that incorporating Fe shifted the absorption peaks of BNNTs into risky UV radiations, which helps researchers develop a vision for controlling and developing advanced materials for various electronic applications.

Investigation electron transport via molecular nanoscale junctions is one of the fundamental steps in developing improved high-performance thermoelectric materials for cooling and converting waste heat into electricity. Density functional theory (DFT) and non-equivalent Green’s function are applied to investigate the electric and thermoelectric properties of Fullerene $({\text{C}}_{60})$ doped with three metalloid ions from the periodic table. The M@C${}_{60}$ (M = P, As and Se) systems have two types of electrodes (gold and graphene). The results show that the electric conductance of G with gold leads is higher than the conductance attached to the graphene leads. Also, ${\text{C}}_{60}$ doped by Se is the best compared with P and as for both gold and graphene electrodes. Moreover, the calculations of HOMO-LUMO resonance shifted toward the high energy (low wavelength) in order $\mathrm{\text{Se}}>\mathrm{\text{P}}>\mathrm{\text{As}}$ due to the electronegativity, which is ordering $\mathrm{\text{Se}}>\mathrm{\text{P}}>\mathrm{\text{As}}$, with the Fano-resonance fixed around E–E${}_F=0$. Meanwhile, the value of Seebeck coefficient S for graphene leads is higher than S linked to the gold lead. Also, the merit figure for ZT and thermal electricity has been investigated.

Heme-type porphyrins can become distorted depending on their environment, altering their chemical and electronic properties. While trends have been established for several ruffle-distorted porphyrins, their research on synthetic models of heme-type porphyrins is limited. We identified a dynamic process on the ruffled porphyrin bis(2-methylpyridinato)iron(III)-Protoporphyrin-IX (2) that does not exist in bis(pyridinato)iron(III)-Protoporphyrin-IX (1). We modeled these molecules as {OMP(2-CH₃Py)₂Fe}${}^{+}$ and {[OMP](Py)₂Fe}${}^{+}$ respectively. Geometry optimization using density functional theory (DFT) suggests the ruffled conformation of 2 (angle x̄ of $-29.7^{\circ }$) and the planar conformation of 1. The calculated electron affinity and ionization potential vary depending upon ruffling. The calculated 0.253 eV difference in electron affinity and the 0.223 eV in ionization potential indicate that the reduction of the planar structure has a higher energy requirement than the ruffled-distorted structure but has a lower energy requirement for its oxidation. We found that these energy differences are not solely attributed to the distortion of the macrocycle. The difference is linked to the interaction between the d${}_{\text{x}\text{y}}$ orbital and the HOMO-1 3a${}_{2\text{u}}$, allowed by symmetry when a porphyrin ring has a ruffled conformation stabilizing the frontier orbitals, thus making the oxidation process have a higher energy barrier. On the other hand, the reduction process is facilitated by the interaction of metal d_π orbitals with the porphyrin 4e. These highlight the distinct differences between the ruffled and the planar conformations.

The ground state geometry of the nickel derivative [Daiquiris(nicotinamide-jN1) nickel(II)]-fumarato-K2O1:O4 has been optimized and is being led toward its quantum chemical analysis in this paper. For more accuracy, we used the 6-311$++$G (d, p) basis set for C, H, N, and O atoms and the LAN2DZ basis set for Ni. The calculated and experimental infrared (IR) spectra for the title molecule are well correlated, and the correlation factor $R^2=0.9947$ shows that the method effectively interprets the molecule’s IR spectra. The electronic properties such as highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energies and associated energy gap have been calculated by Time-Dependent Density Functional Theory (TD-DFT) approach. The natural bond orbital (NBO) analysis of the molecule describes how interatomic charge transfer results in the formation of bonding–nonbonding interactions. The experimental and calculated Ultraviolet visible (UV-Vis) spectra are compared. We anticipate our work will inspire fresh approaches to the title molecule’s ongoing research.

Monolayer Molybdenum disulfide (ML-MoS₂) has emerged as a promising two-dimensional (2D) material with unique electronic, optical and mechanical properties. In this paper, with the aid of first-principles calculations, we explain the optimization of the structural and computational parameters and discuss the electrical properties of ML-MoS₂. The electronic properties were studied comparatively with and without considering the spin-orbit coupling (SOC) effect that shows, ML-MoS₂ has a direct bandgap. A decrease in bandgap energy by 100 meV and a $k$-valley splitting of 100 mV were observed with the inclusion of SOC. The electronic properties were further analyzed using fat band structures and projected density of states (PDOS), which depict the predominant contribution of Mo $d$${}_x$²${}_{-}$${}_y$², $d$${}_{xy}$ and Mo $d$${}_z$² orbital to the valence band maximum (VBM) and conduction band minimum (CBM), respectively. Strain-induced bandgap variation was also observed due to the deformation of the crystal structures by shifting and splitting of the energy levels.

For quite a long time, the scientific community has been searching for a material that surpasses the existing material systems in terms of energy conversion efficiency for photovoltaic applications. In this study, the optoelectronic properties of pure and Al-doped boron arsenide B${{}_{1-}}_x$Al${}_x$As $(x=0,0.125\mathrm{\text{and}}0.25)$ in the zinc blende (ZB) structure were systematically examined using the density functional theory (DFT) and the Modified Becke–Johnson (TB-mBJ) exchange correlation (XC) potential. The Perdew–Burke–Ernzerhof generalized gradient approximation (PBE) functional was used for structural optimization. After considering the ground state lattice constant of 4.82Å then calculating the bandgap energy of pure BAs, which are consistent with experimental and theoretical findings, we estimated the basic electronic and optical characteristics of Al-doped boron arsenide, including band structures, electronic density of state, dielectric function, refractive index, extinction coefficient, absorption and optical conductivity. The unusual and interesting optoelectronic features of the investigated compounds revealed in this work offer substantial promise for improving the energy conversion efficiency of solar cells.

Due to their remarkable mechanical, thermal and electrical characteristics, silicon carbide (SiC) single-walled nanotubes (SWNTs) are an unusual and promising class of materials. Density functional theory (DFT) is used in this study to examine the electrical and structural characteristics of copper-doped SiC armchair SWNTs. It has been discovered that copper doping of SiC armchair SWNTs alters the materials’ electrical characteristics. SiC SWNTs band gap plays a significant role in influencing the electrical conductivity and optical characteristics of the substance. The energy bands i.e., valence band and conduction band of SiC armchair SWNTs overlapped as copper doping concentration increased, altering the materials’ electrical conductivity and optical characteristics. Additionally, a continuous density of states plot and a narrower band gap are frequently employed as markers of ferroelectric behaviour which indicates the existence of a polarizable and highly delocalized electronic system. The significance of copper doping in SiC SWNTs is understood by this study, along with the effects of the doping on the material’s electrical properties.

A comprehensive investigation was conducted to analyze the physical properties, including electronic structure, optical characteristics, and thermoelectric properties, of four zinc blend structures: BAs, AlAs, BBi, and BSb. This analysis utilized first-principles calculations based on Density Functional Theory (DFT) and Boltzmann transport theories, implemented in the WIEN2K simulator program. The compounds examined displayed intriguing electronic and optical properties, such as low indirect band gaps of 0.726, 1.888, 0.867, and 1.51 eV for AlAs, BAs, BBi, and BSb, respectively. Moreover, these compounds exhibited high absorption in the UV–Visible region. Among the four compounds studied, BAs demonstrated exceptional structural stability due to its high bulk modulus and negative formation energy. The thermoelectric study revealed that the Seebeck coefficient decreased with increasing temperature, while the figure of merit was proportional to temperature enhancement. This behavior suggests that the investigated materials hold promise for applications in visible-light solar cell devices.

The potential applications of the cubic phase of CsNbO₃ perovskite have been explored by examining its elastic, electronic, and photocatalytic characteristics using a first-principles approach. The structural robustness when subjected to pressure has been verified by studying the computed elastic constants. Its substantial elastic moduli, hardness, and toughness values propose its suitability for various engineering applications. A transition from flexibility to fragility is observed at pressures exceeding 10GPa. The CsNbO₃ material demonstrates an indirect and narrow band gap, making it a promising candidate in optoelectronic applications. Changes in the band gap due to pressure indicate adjustments in orbital hybridization. The material’s low effective carrier mass and high carrier mobility anticipate favorable electrical conductivity. Assessments of the potentials at the conduction band (CB) and valence band (VB) edges underscore the remarkable capacity of CsNbO₃ for activities such as water-splitting and promoting sustainable energy production.

The electronic and magnetic properties of Be${}_{1-x}$(Gd,Eu,Tb)${}_x$O (with $x$ values of 0.125, 0.25, and 0.375) were systematically investigated using the full-potential linearized augmented plane wave (FP-LAPW) method within density functional theory (DFT). Exchange and correlation potentials were computed employing the generalized gradient approximation (GGA) and GGA plus-modified Becke–Johnson potential (TB-mBJ) approximations. Our findings demonstrate that the incorporation of X into BeO induces magnetism in the compound. Specifically, BeO doped with Gd, Eu, and Tb at $x=0.125,0.25$, and 0.375 exhibits half-metallic behavior, characterized by integer magnetic moments. These results indicate the potential of these compounds to serve as novel half-metallic materials for future spintronics applications, offering exciting prospects in the field.

First-principles based calculations were executed to investigate the sensing properties of ammonia gas molecules on a two-dimensional pristine black phosphorene sheet toward its application as a gas sensor and related applications. We discuss in detail the interaction of ammonia gas molecules on the phosphorene single sheet through the structural change analysis, electronic band gap, Bader charge transfer, and density-of-states calculations. Our calculations indicate that phosphorene could be used as a detector of ammonia, where good sensitivity and very short recovery time at room temperature confirm the potential use of phosphorene in detecting ammonia.

BaHfS₃ and BaZrS₃, two chalcogenide perovskites, show significant promise for next-generation optoelectronic devices due to their adjustable bandgaps, excellent carrier mobilities, and versatile properties. Using density functional theory (DFT) via the WIEN2k package, this study reveals their bandgap energies of 2.05eV and 1.63eV, respectively, situating them in the visible range and making them suitable for photovoltaic (PV) applications. Additionally, both materials satisfy thermodynamic criteria for hydrogen production through water splitting, confirming their photocatalytic potential. Their thermoelectric performance, measured by the figure of merit (ZT) also indicates moderate potential at elevated temperatures. Strain engineering further enhances the PV performance, where a biaxial compressive strain of −6% boosts power conversion efficiencies (PCEs) by 8.34% for BaHfS₃ and 3.30% for BaZrS₃. For photocatalysis, uniaxial and biaxial strains optimize optical absorption and water-splitting kinetics. Furthermore, the thermoelectric properties slightly improve under strain effect. These findings highlight the multifunctional potential of BaHfS₃ and BaZrS₃ for PV, photocatalytic, and thermoelectric applications, with strain engineering providing a robust strategy for performance optimization.

Here, we provide the synthesis process as well as theoretical and experimental research on the molecule known as 7-hydroxy-2-(3,4-dihydroxyphenyl)-3-(piperidin-4-yloxy)-4H-chromen-4-one (7THFP). Quantum mechanical calculations (QM) using several functional levels at a standard basis set have been used to calculate all QM calculations and molecular descriptors. Computational techniques were used to obtain the whole range of vibrational frequencies, IR intensity and Raman activity, all showing excellent agreement with the observed results. The molecule’s electron transport characteristics were explained by Mulliken, NBO, mapped isosurface electron density and Highest Occupied Molecular Orbitals (HOMO)-Lowest Unoccupied Molecular Orbitals (LUMO) investigations. The energy difference between the molecular orbitals (MOs) has also been anticipated. The drug candidate’s ADMET and Lipinski’s rule of five models were used to predict its physicochemical and pharmacokinetic properties, including bioactivity score, lipophilicity and toxicity profiles. The physicochemical profiles of 7THFP indicate favorable drug-likeness, bioactivity and reduced toxicity. Subsequently, molecular docking (MD) analyses were conducted to forecast the ligand’s inhibitory impact on the enzymes. The docking score estimation and in vitro analysis of the drug compound validate its anticancer activity. Lastly, the title molecule was evaluated for its proliferation and cytotoxicity effects on human MCF-7 cell lines. These investigations demonstrate that the product exhibits promising characteristics as a drug candidate and may serve as a model for further enhancement.

Novel nonlinear optical (NLO) molecules are designed in order to meet their tremendous demand in the field of optics and electronics. The first attempt of the structural tailoring of disperse orange 3 (DO3)-an azodye is made to develop nineteen derivative molecules (D1-D19). Two approaches were opted for preparing 4 groups of molecules. The first one was the extension of $\pi$-conjugated system and the second strategy was the use of diverse electron donor and acceptor groups to develop unique donor-$\pi$-acceptor systems. Density functional theory (DFT) calculations were performed for in silico characterization of the studied molecules. The polarizability (${\alpha }_o$) and first-order hyperpolarizability (${\beta }_o$) values gave the insight of nonlinear optical response. All the designed molecules with extended conjugation and unique electron donor and acceptor group combination showed remarkably high ${\alpha }_o$ and ${\beta }_o$ values. The highest hyperpolarizability value (42477.48 a.u.) with several thousand increases than ${\beta }_o$ (7113.25 a.u.) of reference DO3, was depicted by D19 of the designed derivatives. This can be attributed to greater intramolecular charge transfer (ICT) in it. Various interaction studies were made and global reactivity descriptors (GRDs) were calculated to determine their chemical nature and stability. The outcome of our study suggests that the designed molecules are potential candidates for NLO applications, like energy conversion for producing tunable lasers and high-resolution spectroscopic studies.

Nitrosourea (NU) and hydroxyurea (HU) are recognized as chemotherapeutic agents. Their efficiency is restricted by the risk of misuse and the release of trace amounts of un-metabolized chemicals into the environment. Numerous potential negative effects may arise from the use of these drugs. Nanomaterials for drug detection are essential in pharmaceutical research, particularly cancer therapeutic applications such as HU and NU. This study sought to investigate the sensitivity of the C${}_{24}$N${}_{24}$ nanocage in detecting HU and NU via density functional theory (DFT). The interactions between HU/NU drugs and the C${}_{24}$N${}_{24}$ nanocage were investigated using optimized geometries, adsorption energies, FMO, NCI, NBO and QTAIM analyses via DFT and TD-DFT at the B3LYP-D3/6-31G(d,p) theoretical level. The adsorption energy estimations of –24.47 kcal/mol for the NUG complex and –19.90 kcal/mol for the HUB complex indicate that the HU/NU medicines are strongly adsorbed onto the C${}_{24}$N${}_{24}$, and the process is exothermic. NCI and QTAIM analyses have shown noncovalent interactions, primarily van der Waals forces, between C${}_{24}$N${}_{24}$ and HU/NU drugs. When HU/NU interacts with the C${}_{24}$N${}_{24}$ surface, new energy levels are generated in the C${}_{24}$N${}_{24}$ PDOS. Upon evaluating the $E_{\text{g}}$ value, sensitivity and recovery time as parameters of the nanocage’s sensing efficacy, it was determined that the HUB complex exhibits the best conductivity (5.67 × 10${}^{12}$ S/m), fine sensitivity (0.2560) and most stability due to its small energy gap of 1.67 eV value. The complex NUG has the lowest recovery time with a value of 5.15 × 10${}^{-17}$ s. As a result of its recovery time, the C${}_{24}$N${}_{24}$ nanocage is highly desirable for its potential application as an HU/NU drug sensor. This demonstrates that HU/NU drugs can be efficiently identified by the C${}_{24}$N${}_{24}$ nanocage. Our findings indicate that the C24N24 nanocage may enhance drug detection (HU/NU), indicating possible pathways for further advancement.