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By utilizing FP-LAPW, the structure, electronic, optical, mechanical and Transport characteristic of A2BAuCl6 (A = K/Rb/Cs, B = Sc/Y) were examined by using DFT. The analysis to the band structure plot of the Halide double perovskites (HDP’s) being studied indicated the existence of indirect band-gaps. The compounds A2BAuCl6 (A = K/Rb/Cs, B = Sc/Y) exhibit anisotropic properties, except one compound as seen by their respective shear anisotropy readings of 0.629, 0.532, 1.006, 0.682, 0.803 and 0.977. The materials have inherent ductility, as indicated by their calculated Poisson’s ratios in the range of 0.30 to 0.35. The examined (HDP’s) materials appear to possess indirect band-gaps, as indicated by the band structure plots. The functional inorganic perovskites A2BAuCl6 (A = K/Rb/Cs, B = Sc/Y) haven’t similar band-gap values, as determined using the TB-mBJ (modified Becke Johnson) and TB-mBJ + Soc (Spin orbital coupling) assumptions. The visible and ultraviolet domain have prominent peaks, suggesting potential applications of the compounds in solar cells. Moreover, examination of additional optical characteristics such as reflectivity, conductivity, electron energy loss, and absorption coefficients suggest that it possesses the inherent features of a semiconductor. The maximum figure of merit for all the student compounds is above 0.74. The simulated output forms the foundation for A2BAuCl6 (A = K/Rb/Cs, B = Sc/Y) and are of practical importance for multijunction solar cells.

The Yamaguchi reagent, based on 2,4,6-trichlorobenzoyl chloride (TCBC) and 4-dimethylaminopyridine (DMAP), is an efficient tool for conducting the intermolecular (esterification) reaction between an acid and an alcohol in the presence of a suitable base (Et3N or iPr2NEt) and solvent (THF, DCM, or toluene). The Yamaguchi protocol is renowned for its ability to efficiently produce a diverse array of functionalized esters, promoting high yields, regioselectivity, and easy handling under mild conditions with short reaction times. Here, the recent utilization of the Yamaguchi reagent was reviewed in the synthesis of various natural products such as macrolides, terpenoids, polyketides, peptides, and metabolites.

In present investigation, we elucidated the structural, elastic, optical, mechanical, electronic, and thermodynamics properties of AB2 (A = Hf, Zr, and BCo, W) laves phases via first principles scheme of density functional hypothesis. The effect of pressure on various physical aspects up to 100 GPa accounted to this research and found significant changes at different pressures. The results we obtained for the present enquiry have been quantified with the previous research of relevant work and relatively better performance is obtained. The cell parameters as well as unit cell volume are found to be decreased with applied pressure since the interatomic distances of atoms became shorter with pressure. The negative formation enthalpy ensures the chemical and thermodynamical stability of the studied phases. Using Born approximation criterion the mechanical stability has been verified where the phase transition of AB2 (A = Hf, and BCo, W) and AB2 (A = Zr and BCo, W) has been observed after 20 GPa and 40 GPa respectively. It was observed that elastic moduli of AB2 (A = Hf, Zr, and BCo, W) increases with increasing pressure. The higher C11 values among three elastic moduli show higher resistance to linear compression for the current study which is even better than the previously reported result. Mechanical performance has been measured in terms of shear modulus (G), bulk modulus (B), and Young modulus (E) using Vigot-Reuss-Hill method. The estimated data shown pressure rising G, B, and E values indicates dominating stiffness properties under applied stress which ensure their industrial applications. The increased nature of machinable index of all these phases unsure their huge applications in cutting tool geometry, cutting fluids and and plastic strain. The Poisson and Pugh ratio analysis suggests that at zero pressure only the phase HfCo2 shows brittle nature and the other phases AB2 (A = Zr, and BCo, W) show ductile nature from 0 to 100 GPa. The electronic properties investigated through density of state (DOS) calculations revels the metallic characteristics of the titled phases. Decrease in total DOS at high pressure is observed for all the phases. Under pressure it was found that optical indices like absorption coefficient, conductivity, loss function, reflectivity, and dielectric functions are gradually shifted toward higher energies confirming that these materials can be used solar cells to reduce solar heating, and in UV light-based device for high absorption. Higher Debye temperature, thermal conductivity and melting temperature of AB2 (A = Hf, Zr, and BCo, W) are found at ambient condition and these parameters are increasing with increasing pressure which ensure the high temperature industrial applications of these phases. Among four laves phases, relatively higher mechanical, optical, and thermodynamic performance is obtained for HfW2 compound.

Abstract Since two‐dimensionalal (2D) materials have distinct chemical and physical properties, they are widely used in various sectors of modern technologies. In the domain of diagnostic biodevices, particularly for point‐of‐care (PoC) biomedical diagnostics, 2D‐based field‐effect transistor biosensors (bio‐FETs) demonstrate substantial potential. Here, in this review article, the operational mechanisms and detection capabilities of biosensing devices utilizing graphene, transition metal dichalcogenides (TMDCs), black phosphorus, and other 2D materials are addressed in detail. The incorporation of these materials into FET‐based biosensors offers significant advantages, including low detection limits (LOD), real‐time monitoring, label‐free diagnosis, and exceptional selectivity. The review also highlights the diverse applications of these biosensors, ranging from conventional to wearable devices, underscoring the versatility of 2D material‐based FET devices. Additionally, the review provides a comprehensive assessment of the limitations and challenges faced by these devices, along with insights into future prospects and advancements. Notably, a detailed comparison of FET‐based biosensors is tabulated along with various other biosensing platforms and their working mechanisms. Ultimately, this review aims to stimulate further research and innovation in this field while educating the scientific community about the latest advancements in 2D materials‐based biosensors.

The utilization of thermally activated delayed fluorescence (TADF) materials in highly proficient organic light-emitting diodes (OLEDs) has attracted much attention. Based on TADF material TPA-QNX(CN)2, a series of three-dimensional donor-acceptor (D-A) triptycenes have been designed via structural modification of D-fragment. The influences of different D-fragments with various electron-donating strengths on the singlet-triplet energy gap (ΔEST), emission wavelength (λem), and electron/hole reorganization energy (λe/λh) are extensively studied by applying density functional theory (DFT) coupled with time-dependent density functional theory (TD-DFT). The computed results imply that as the electron-donating strength of the D-fragments increases, the ΔEST value decreases and λem is red-shifted for the molecules using the same acceptor units. Analogously, the 1CT‒3CT state splitting (ΔEST (CT)) is also decreased by enlarging the twist angle (β) between the phenyl ring and alternative D-fragment. Therefore, efficient color tuning within a broad emission range (434–610 nm), as well as small ΔEST (CT) values (0.01–0.05 eV), has been accomplished by structural modification of the D-fragments. The greater electron-donating strength, the smaller ΔEST, and the smaller λh for PPXZ-QNX(CN)2 make it the best candidate among all the designed molecules.

The violet-to-blue thermally activated delayed fluorescence (TADF) emitters were created employing several substituents based on 5,5-dimethyl-5,10-dihydropyrido [2,3-b][1,8] naphthyridine-diphenylsulphone (DMDHPN-DPS) called 1a via “CH/N” and “H/CN” substitutions at the diphenylsulphone acceptor (DPS) moiety. The parent compound 1a was selected from our former work after extensive research employing “CH/N” substitution on Dimethyl-acridine (DMAC) donor moiety. There is a little overlap amid the highest occupied molecular orbitals (HOMOs) and lowest un-occupied molecular orbitals (LUMOs) due to the distribution of HOMOs and LUMOs primarily on the DMDHPN donor and the DPS acceptor moieties, respectively. It resulted in a narrower energy gap (∆EST) between the lowest singlet (S1) and triplet (T1) excited state. In nearly all derivatives, the steric hindrance results in a larger torsional angle (85°–98°) between the plane of the DMDHPN and the DPS moieties. The predicted ΔEST values of the compounds with “H/CN” substitution were lower than those of the comparable “CH/N” substituents, demonstrating the superiority of the reversible inter-system crossing (RISC) from the T1 → S1 state. All derivatives have emission wavelengths (λem) in the range of 357–449 nm. The LUMO → HOMO transition energies in the S1 states are lowered by the presence of –CN groups or –N = atoms at the ortho or meta sites of a DPS acceptor unit, causing the λem values to red-shift. Furthermore, the λem showed a greater red-shift as there were more–CN groups or –N = atoms. Three of the derivatives named 1b, 1g, and 1h, emit violet (394 nm, 399 nm, and 398 nm, respectively), while two others, 1f and 1i, emit blue shade (449 nm each) with reasonable emission intensity peak demonstrating that these derivatives are effective violet-to-blue TADF nominees. The lower ΔEST value for derivative 1i (0.01 eV) with λem values of 449 nm make this molecule the finest choice for blue TADF emitter amongst all the studied derivatives. We believe our research might lead to the development of more proficient blue TADF-OLEDs in the future.

The field of point particle dynamics is correlated with the study of particle dynamics around the black hole and one can initiate the study of a more complex motion of extended/celestial bodies. In this article, we consider the study of the dynamics of the neutral/charged particles around the quantum corrected-Schwarzschild black hole and Schwarzschild black hole. We investigate Noether symmetries and their conservation laws corresponding to the quantum corrected-Schwarzschild spacetime. We also study the effect of angular momentum, quantum parameters and magnetic field on the dynamics of neutral and charged particles around the quantum corrected-Schwarzschild black hole and Schwarzschild black hole.

Chalcone derivatives gained significant consideration from scientific community due to their potential applications ranging from better biological activity to the efficient semiconducting properties. Present investigation deals with the in-depth study of three chalcone derivatives (2E)-1-(2,5-Dimethyl-3-thienyl)-3-(2-methoxyphenyl)prop-2-en-1-one (1), (2E)-3-(3,4-Dimethoxyphenyl)-1-(2,5-dimethylthiophen-3-yl)prop-2-en-1-one (2), and (E)-1-(2,5-Dimethyl-3-thienyl)-3-(2,4,5-trimethoxyphenyl)prop-2-en-1-one (3) highlighting their optoelectronic, charge transport (CT) and nonlinear optical (NLO) response. The ground and excited state geometries are optimized by applying density functional theory (DFT) and time dependent DFT, respectively. The effect of electron donating groups on the frontier molecular orbitals, absorption and emission wavelengths are investigated and discussed thoroughly using the quantum chemical calculations. The comprehensive intra-molecular charge transfer (ICT) is perceived from the occupied orbitals to the unoccupied molecular orbitals. A novel structure-property relationship is established on the basis of their calculated electronic structures, frontier orbitals and density of states. The electro-optical and nonlinear optical (NLO) properties are finely tuned in the chalcone derivatives comprising of di- and tri-methoxy groups at peripheral. The nature of the p-type and ambipolar charge transport behavior of the compounds 1–3 is limelighted on the basis of their ionization potentials, electron affinities, reorganization energies, transfer integrals and intrinsic mobility. The mono- and di-substituted methoxy chalcone derivatives show the ambipolar performance owing to the better transfer integral and intrinsic mobility values for hole and electron. Whilst tri-methoxy at peripheral would lead the p-channel characteristics due to the balanced reorganization energy (hole and electron) and superior hole transfer integrals leads to higher hole intrinsic mobility. Keywords: Semiconductors, Density functional theory, Optoelectronic properties, Charge transport properties, Intrinsic mobility

The oxazole compounds are being used for multifunctional purposes ranging from organic light emitting diodes, organic thin film transistors, and photovoltaic to the nonlinear optical materials. In this study, several structural, electro-optical, charge transport and nonlinear optical properties of (4Z)-4-Benzylidene-2-(4-methylphenyl)-1,3-oxazol-5(4H)-one (BMPO) have been investigated. Density functional theory (DFT) and time dependent DFT are very accurate and reasonable approaches to optimize the ground and excited state geometries, respectively. Thus, in the present study DFT and TDDFT methods with the B3LYP/6-31G∗∗ levels of theory have been applied to shed some light on the structure-property relationship, frontier molecular orbitals (FMOs), optical properties. A clear intra-molecular charge transfer (ICT) from the highest occupied molecular orbitals (HOMOs) to the lowest unoccupied molecular orbitals (LUMOs) has been observed. The ionization potentials (IP), electron affinities (EA), total and partial densities of states have been discussed intensively. The electron reorganization energy of oxazole compound (BMPO) is smaller than the hole reorganization energy revealing that it might be good electron transport contender in OLED. The electron reorganization energy of BMPO is calculated to be 0.223 eV that is smaller than the perfluoropentacene (value is 0.250 eV), which is famous n-type semiconductor material. The first pathway of BMPO has almost comparable hole and electron transfer integral values whereas the calculated electron reorganization energy (0.223 eV) is considerably lower than the hole reorganization energy (0.381 eV) which leads to superior electron intrinsic mobility of the studied oxazole derivative as compared to the hole one. It is expected that BMPO might be excellent electron transport material.

We designed novel derivatives of 4,6-di(thiophen-2-yl)pyrimidine (DTP). Two benchmark strategies including mesomerically deactivating group, as well as the extension of π-conjugation bridge (acene-fusion) have been employed to enhance the electrical and charge transport properties. The density functional theory (DFT) and time dependent DFT methods have been used to get optimized geometries in ground and first excited state, respectively. The structural properties (geometric parameters), electronic properties (frontier molecular orbitals; highest occupied and lowest unoccupied molecular orbitals), photophysical properties (absorption, fluorescence and phosphorescence), and important charge transport properties are discussed to establish a molecular level structure–property relationship among these derivatives. Our calculated electronic spectra i.e., absorption, fluorescence and phosphorescence have been found in good semi-quantitative agreement with available experimental data. All the newly designed derivatives displayed significantly improved electron injection ability than those of the parent molecule. The values of reorganization energy and transfer integral elucidate that DTP is a potential hole transport material. Based on our present investigation, it is expected that the naphtho and anthra derivatives of DTP are better hole transporters than those of some well-known charge transporter materials like naphthalene, anthracene, tetracene and pentacene.

The corner stone of present study is to tune the electro-optical and charge transport properties of donor-bridge-acceptor (D-π-A) triphenylamine (TPA) derivatives. In the present investigation, an electron deficient moiety (pyrimidine), electron-rich moiety (thiophene) and oligocene (benzene, naphthalene, anthracene, tetracene and pentacene) have been incorporated as π-spacer between the donor TPA unit and cyanoacetic acid acceptor and anchoring group. The elongation of bridge usually affects the energy levels, i.e., higher the highest occupied molecular orbital (HOMO) while lower the lowest unoccupied molecular orbital (LUMO) thus reduces the HOMO–LUMO energy gap. The lowered LUMO energy levels of cyano-{2-[6-(4-diphenylamino-phenyl)-pyrimidin-4-yl]-tetraceno[2,3-b]thiophen-8-yl}-acetic acid (TPA-PTT4) and cyano-{2-[6-(4-diphenylamino-phenyl)-pyrimidin-4-yl]-pentaceno[2,3-b]thiophen-9-yl}-acetic acid (TPA-PPT5) dyes revealed that electron injected from dye to semiconductor surface might be auxiliary stable resulting in impediment of quenching. The broken co-planarity between the π-spacer conceiving LUMO and the TPA moiety would help to impede the recombination process. Moreover, it is expected that TPA derivatives with the tetracenothiophene and pentacenothiophene moieties as π-bridge would show better photovoltaic performance due to lowered LUMO energy level, higher electronic coupling constant, light harvesting efficiency and electron injection values.