Perdew Burke Ernzerhof Generalized Gradient Approximation Research Articles

Mechanical, Magnetic, and Optical Characteristics of Tm‐Based Chalcogenides for Energy‐Harvesting Applications

Herein, a comprehensive theoretical analysis of Tm‐based chalcogenides MgTm2Y4 (Y = S, Se) is performed to understand magnetic, optical, mechanical, and transport characteristics. And, Perdew–Burke–Ernzerhof generalized gradient approximation (PBEsol‐GGA) functional and modified Becke–Johnson (mBJ) potentials are employed while computing the mechanical and spin‐polarized electronic properties, respectively. The structural stability of both spinels is confirmed using formation energy and Born stability criteria. Both spinels are found exhibiting ductile nature according to the computed Pugh's and Poisson's ratios. For observing the room‐temperature ferromagnetism, Curie temperature is calculated. Furthermore, spin‐polarized electronic properties reveal that both spinels exhibit ferromagnetic nature, which is induced due to coupling among Tm‐ and S/Se‐related constituent states. The potential optoelectronic applications are suggested by computing and discussing dielectric constant, refractive index, and absorption coefficient. BoltzTraP code is used to investigate the thermoelectric features of MgTm2Y4 (Y = S, Se) in the 200–800 K temperature range.

First‐Principles Calculations to Investigate Electronic, Elastic, Magnetic, and Optical Properties for B1, B2, and B3 Phase for Sr0.875Mn0.125O with and Without Relaxation Structure

AbstractIn this work, the structural, electronic, elastic, optical, and magnetic properties for the B1, B2, and B3 phases of Sr0.875Mn0.125O with relaxed structure (RS) and unrelaxed structure (URS) are investigated. The investigations are accomplished by the adoption of first‐principle methods established on spin‐polarized density functional theory, based on the full‐potential linearized augmented plane wave method as implemented in the WIEN2k code, where the electronic exchange‐correlation potential is studied by the Perdew–Burke–Ernzerhof generalized gradient approximation (GGA‐PBEsol) and the revised TB‐mBJ rapprochement. The negative formation energy and elastic constant that are acquired indicate the thermodynamical and mechanical stability of all these structures. The ternary Sr0.875Mn0.125O alloys for all structures show half‐metallic ferromagnetic behavior with a spin polarization of 100 % at the Fermi level, except the B2 phase without unrelaxed structure (URS). The total magnetic moments are 5 µB for all compounds and the interaction is ferromagnetic between Mn─Sr and Mn─O sites. Optical properties such as refractive index and the optical reflectivity for these alloys are computed and discussed. These materials are half‐metallic ferromagnets, and they can be desirable applicants for spintronics implementations and ultraviolet spectra.

First-principles calculations to investigate structural, electronic and magnetic anisotropy energy of ZnFe[formula omitted]O[formula omitted] spinel ferrite for spintronics applications

Structural, electronic and magnetic investigations of ZnFe2O4 have been made by using density functional theory with Perdew–Burke–Ernzerhof Generalized-Gradient Approximation as exchange and correlation functional. Additionally, the effect of Hubbard, U, and spin orbit coupling, SOC on electronic and magnetic properties has also been observed. The U-value for Zinc and Iron are used, 6.0 eV (0.44 Ry) and 4.3 eV (0.316 Ry) respectively. The optimized lattice parameter matches well with experimental with mere percentage difference of 0.039%. This optimized lattice constant is used for SCF calculations to calculate the above mentioned properties of zinc ferrite. It is found that zinc ferrite have high value of magnetic moments, 19.721μB, 20.003μB, and 19.580μB for PBE, PBE with Hubbard, and with spin orbit coupling respectively. The magneto crystalline anisotropy energy calculations confirm the utility of this material for spintronics device fabrication.

The spin-polarized electronic and optical properties of novel Ba2TaXO6 (X = Co, Fe, In) for optoelectronic applications: An ab-initio study

First principles calculations were carried out to examine the spin-polarized electronic and optical characteristics of novel Ba2TaXO6 (X = Co, Fe, In) double perovskites in the monoclinic phase, employing the full-potential linearized augmented plane wave technique (FP-LAPW) based on the density functional theory (DFT). To calculate the total energy, the Perdew-Burke-Ernzerhof generalized gradient approximation (PBE-GGA) were used. The electronic study with the TB-mBJ approach shows a metallic nature for Ba2TaCoO6 and a half-metallic nature for Ba2TaFeO6 and Ba2TaInO6 materials. The calculated density of states, nearly show similar features for all the materials. The PDOS were calculated, which displays the contribution of several electronic states for these compounds in the distribution. Additionally, in the optical spectra, the dielectric functions, absorption coefficients, refractive indexes, extinction coefficients, energy loss function, and reflectivity parameters were calculated in the energy range 0–14 eV. The optical parameters demonstrate that the materials are the potential candidates for opto-electronics devices.

First principles study of the structural, half-metallic ferromagnetism, magnetic, and transport properties of KXO2 (X = Pr, Nd, and Pm) hexagonal oxides

The density functional theory (DFT) studies are made to calculate the electronic, magnetic, and transport characteristics of potassium lanthanide KXO2 (X = Pr, Nd, and Pm) oxides have been studied by using the WIEN2K code. Perdew Burke Ernzerhof-Generalized Gradient approximation (PBE-GGA) is used for the exchange-correlation energy of the crystal structures in the hexagonal phase. However, the volume-optimized graphs depict that these compounds are energetically stable in the ferromagnetic state. Moreover, the studies of the spin-up channels of the band structure and density of states (DOS) reveal their metallic behavior whereas semiconductor nature has been noticed through spin-channels. Therefore, studied materials have half metallicity nature with 100% spin polarization at the Fermi level (EF). Total and partial magnetic moments of KXO2 (X = Pr, Nd, and Pm) and individual atoms exist due to unpaired 4f electronic states of the lanthanide ions, present at the EF. The energy difference between anti-ferromagnetism and ferromagnetism versus the volume optimization curve gives the curie temperature (Tc). The volume optimization curves show a flat region where both magnetic states have similar energies. This means the material can exist at the equilibrium volume in either state. Finally, thermoelectric properties are calculated by the BoltzTraP code. Our results unveil that these potassium-based lanthanide oxides are potential materials for devising spintronics devices and lifting future practical applications.

Electronic Properties, Linear and Nonlinear Performance of KAgCh (Ch = S, Se) Compounds: A First-Principles Study

In the current study, the peculiar nonlinear optical (NLO) properties of KAgCh (Ch = S, Se) and their structural, electronic, and thermodynamic properties are computed utilizing the FP-LAPW (full-potential linearized augmented plane wave) approach as embedded in Wein2K code. The Perdew–Burke–Ernzerh of generalized gradient approximation (PBE-GGA) was considered for the structural optimization. The computed bandgaps are found to be 2.57 and 2.39 eV for KAgS and KAgSe, respectively. Besides the structural and electronic properties, we also computed the refractive indices n(ω), surface energy loss function (SELF), and nonlinear optical susceptibilities. The estimated refractive indices, energy band gap, and their frequency dependence for the investigated KAgCh (Ch = S, Se) compounds, along with the NLO coefficients, are found to be in good agreement with the earlier reports. These current findings suggest that KAgCh (Ch = S, Se) can be recommended for nonlinear optical applications in the near-infrared spectrum.

Investigation of structural, mechanical, dynamic stability and electronic properties of anti-perovskite nitrides ANLa3 (A = Al, Ga): a DFT and DFPT studies

Various properties of anti-perovskites ANLa3 (A = Al, Ga) are investigated using the density functional theory (DFT). The GaNLa3 properties are studied for the first time. The computed lattice parameter of AlNLa3 is found to be close to other theoretical and experimental results. The mechanical stability of the present compounds are confirmed by the elastic constants estimated through the calculations. Furthermore, bulk modulus, shear modulus and Young’s modulus are evaluated. In this report, the dynamic stability and formation energy of AlNLa3 and GaNLa3 alloys are also highlighted. The state density functional perturbation theory (DFPT) is used to reveal the phonon calculation showing that the studied compounds are dynamically stable. Indeed, with a negative formation energy, it has been predicted that the GaNLa3 compound can be synthesized experimentally. Moreover, the electronic properties are studied using the Perdew–Burke–Ernzerhof Generalized Gradient Approximation (GGA-PBE) as well as a more sophisticated exchange-correlation Yukawa Screened PBE0 (YS-PBE0) hybrid functional.It has been found that the computed energy band structures within both approaches, that the anti-perovskites AlNLa3 and GaNLa3 are metallic nature. The total density of states (TDOS) and partial density of states (PDOS) are also calculated to show in evidence the contribution of atoms orbitals in the formation of bands.

Role of spin-orbit coupling effects in rare-earth metallic tetra-borides: a first principle study

We have investigated the electronic structure of rare-earth tetraborides, $\textrm{RB}_{4}$, using first-principle electronic structure methods (DFT) implemented in Quantum Espresso (QE). In this article we have studied heather-to neglected strong spin-orbit coupling (SOC) effects present in these systems on the electronic structure of these system in the non-magnetic ground state. The calculations were done under GGA and GGA+SO approximations using ultrasoft pseudopotentials and fully relativistic ultrasoft pseudopotentials (for SOC case). Perdew-Burke-Ernzerhof generalized gradient approximation (PBE-GGA) exchange-correlation functionals within the linearized plane-wave (LAPW) method as implemented in QE were used. The projected density of states consists of 3 distinct spectral peaks well below the Fermi energy and separated from the continuum density of states around the Fermi energy. The discrete peaks arises due to rare-earth $s$-orbital, rare-earth $p$ + B $p$ and B $p$-orbitals while the continuum arises due to hybridized B $p$, rare-earth $d$ orbitals. Upon inclusion of SOC the peak arising due to rare-earth $p$-orbitals gets split into two peaks corresponding to $j=0.5$ and $j=1.5$ configurations. In case of $\textrm{LaB}_{4}$, in the presence of SOC, spin-split $4f$ orbitals contributes to density of states at the Fermi level while the density of states at the Fermi level largely remains unaffected for all other materials under consideration.

Spin-state gaps and self-interaction-corrected density functional approximations: Octahedral Fe(II) complexes as case study.

Accurate prediction of a spin-state energy difference is crucial for understanding the spin crossover phenomena and is very challenging for density functional approximations, especially for local and semi-local approximations due to delocalization errors. Here, we investigate the effect of the self-interaction error removal from the local spin density approximation (LSDA) and Perdew-Burke-Ernzerhof generalized gradient approximation on the spin-state gaps of Fe(II) complexes with various ligands using recently developed locally scaled self-interaction correction (LSIC) by Zope et al. [J. Chem. Phys. 151, 214108 (2019)]. The LSIC method is exact for one-electron density, recovers the uniform electron gas limit of the underlying functional, and approaches the well-known Perdew-Zunger self-interaction correction (PZSIC) as a particular case when the scaling factor is set to unity. Our results, when compared with reference diffusion Monte Carlo results, show that the PZSIC method significantly overestimates spin-state gaps favoring low spin states for all ligands and does not improve upon density functional approximations. The perturbative LSIC-LSDA using PZSIC densities significantly improves the gaps with a mean absolute error of 0.51eV but slightly overcorrects for the stronger CO ligands. The quasi-self-consistent LSIC-LSDA, such as coupled-cluster single double and perturbative triple [CCSD(T)], gives a correct signof spin-state gaps for all ligands with a mean absolute error of 0.56eV, comparable to that of CCSD(T) (0.49eV).

Structural, electronic, magnetic, and optical investigations of sodium chalcogenides: First-principles calculations

The electronic, magnetic, and optical properties of NaS and NaSe compounds have been studied by using first-principles calculations based on density-functional theory and full-potential linearized augmented plane-wave method. The Perdew–Burke–Ernzerhof generalized gradient approximation (PBE-GGA) and modified Becke–Johnson (mBJ-GGA) have been used to deal with the exchange-correlation potential. The PBE-GGA and mBJ-GGA electronic calculation of the spin-up configuration shows an insulating behavior, while the spin-down shows a metallic behavior. In addition, both PBE-GGA and mBJ-GGA agree that the total magnetic moment per unit cell for these compounds is 1 μB. From optical calculations, we see that ε1(0) value in the spin-up channel is positive, which shows an insulating character, while it has a large negative value for the spin-down configuration, which shows a metallic character. The NaS and NaSe refractive index n(ω) indicates a metallic demeanor as the real and imaginary parts of the dielectric constant.

Theoretical expolartion of site selective Perovskites for the application of electronic and optoresponsive memory devices

Now a days, the advent of energy efficient artificial neuromorphic hardware is facing variability and uniformity related state of art issues. DFT deals with this plethora at the atomistic level by introducing innovative composites of improved neuromorphic performance. In this theoretical study unprecedented potential of non-toxic and high dielectric strength of BaHfO 3 is investigated for storage devices. For improving the variability and uniformity related state of art issues, the influence of substitutional doping ofsingle rare earth metal cation at “A” (Ba atom) and “B” (Hf atom) sites of the studied cubic ABO 3 supercell is explored in formation of conducting filaments (CFs). Formation of strongly confined CFs in BaHf 1-x SmO 3 will provide an intriguing roadmap for practical application by resolving the variability and uniformity issues in electronic and optoresponsive memory devices. Alterations of structural and electronic properties by single rare earth dopants will assist in understanding the filamentary based resistive switching in BaHfO 3 . Change in resistance state caused by incident photon stimuli based extrinsic trigger revealed the intriguing neuromorphic nature of BaHfO 3 . The findings of this study will enrich the research exploring the perovskite based resistive switching materials for low power consuming resistive random access memory devices in neuromorphic applications. • The electronic modification subsequently with the creation of the rare earth metal (REM) ion dopant in cubic BaHfO 3 using Perdew-Burke-Ernzerhof Generalized gradient approximation (PBE-GGA) in addition to Hubbered parameter (GGA + U) are performed to investigate the A (Ba atom) and B (Hf atom) site impact of REM (Ce, La, Sm) dopant for switching process and application of optoelectronic devices. • Electronic properties showed sensitivity towards A and B site doping. • Integrated charge density plots depicted charge transfer mechanism. • The conductivity of the phases increased with substitutional replacement of A and B site atom by REM; and eventually resulted that the considered phase opted for low resistance state. • BaHf (1-x) Sm x O 3 is found to be composite with better optoelectronic properties.

An ab initio investigation of the structural, mechanical, electronic, optical, and thermoelectric characteristics of novel double perovskite halides Cs2CaSnX6 (X = Cl, Br, I) for optically influenced RRAM devices.

Hybrid lead halide perovskites have been considered as promising candidates for a large variety of optoelectronic applications. By exploring novel combinations of lead-free double perovskite halides, it is possible to find a suitable replacement for poisonous lead halide perovskites, enhancing electronic and optical response for their application as optically-influenced resistive switching random access memory (RRAM). In this work, the structural, mechanical, elastic, electronic, optical, and thermoelectric characteristics of lead-free double halide perovskites were investigated by Vienna ab initio simulation package (VASP) to explore their role in RRAM. From the analysis of mechanical constraints, it is clear that all three composites of Cs2CaSnX6 (X = Cl, Br, I) are mechanically stable and ductile in nature. The electronic bandgap with and without spin-orbit coupling (SOC), and total and sub-total density of states (TDOS, sub-TDOS) have been calculated using the Perdew-Burke-Ernzerhof generalized gradient approximation (PBE-GGA) potentials. The observed direct band gaps of 3.58 eV, 3.09 eV, and 2.60 eV for Cs2CaSnCl6, Cs2CaSnBr6, and Cs2CaSnI6, respectively, reveal the suitability of these specified composites as resistive switching material for RRAM devices. Additionally, the optical characteristics, such as complex refractive index, absorption coefficient, and reflectivity of the compounds under consideration have been calculated under the action of incident photons of 0 to 14 eV energy. The thermoelectric properties of Cs2CaSnX6 (X = Cl, Br, I) double perovskite halide were computed and analyzed with the help of the BoltzTraP Code.

First principle calculation of structural, electronic, optical, elastic and thermodynamic properties of group IIA metal iodides: Structure-property correlation

The Structural, Electronic, Optical, Elastic and Thermodynamic Properties of Group IIA Metal Iodides were investigated using DFT calculations employing full potential linearized augmented plane wave plus local orbitals with Perdew Burke Ernzerhof-Generalized Gradient Approximation (PBE-GGA). We have also carried out band structure calculations using some other exchange-correlation functionals such as LSDA, PBEsol-GGA,WC-GGA and TB-mBJ for all the compounds. Among these iodides, MgI2 and CaI2 have same trigonal structure while SrI2 and BaI2 follow same orthorhombic structure with BeI2 having orthorhombic structure of entirely different space group. All the calculated properties show consistently the similarity for the iodides of same structure following the structure-property correlation. Bands are fewer and less dense for MgI2 and CaI2 in contrast with many and denser bands of SrI2 and BaI2 in comparison to altogether different moderately dense bands of BeI2. The band structure reveals an indirect band gap of 4.08 eV, 3.5 eV, 3.58 eV for BeI2, MgI2, CaI2 respectively and a direct band gap of 3.79, 3.35 for SrI2, BaI2 respectively. The optical anisotropy with excitonic features exhibited by BeI2, MgI2 and CaI2 is clearly absent in SrI2 and BaI2. The calculated elastic constants show that all these compounds are quite mechanically stable having the magnitude of elastic anisotropy in the order: BeI2>CaI2>BaI2>MgI2>SrI2. All the thermodynamic properties show bunching according to their structure consistent with structure-property correlation. Debye temperatures were calculated for BeI2, MgI2, CaI2, SrI2 and BaI2 at room temperature and zero pressure as 183.53 K, 188.51 K, 166.98 K, 151.12 K and 135.55 K respectively. Many parameters of these properties are new in the literature. A reasonable agreement between our calculated and available theoretical/experimental band gaps of these iodides in the literature justifies the accuracy of the calculations of other properties. All the properties of these iodides are explained consistently and comprehensively in terms of their structure-property correlation.

First-principles Calculations of the Electronic Structure and Optical Properties of Graphene-like InxAl1-xN Monolayers

This paper employs the Heyd-Scuseria-Ernzerhof (HSE) function to research electronic structures of monolayer InxAl1-xN with different compositions (x = 0, 0.25, 0.5, 0.75, 1) based on the first-principles, and the optical properties of single-layer InxAl1-xN are calculated by Generalized Gradient Approximation-Perdew Burke Ernzerhof (GGA-PBE) function. The influence of the electronic structure on the properties has been analyzed. Then the influence of doping quantity on the characteristics has been summarized, which also indicates the trend of the complex dielectric function and absorption spectrum. The calculation results show that with the increase of x, the static dielectric constant increases, the electron transition ability increases, and the absorption peak intensity in the light absorption spectrum increases. It can conclude that the InxAl1-xN compound can theoretically achieve the adjustable Eg and photoelectric performance with x, which will apply in making various optoelectronic devices, including solar cells and sensors.

First principles calculations to investigate electronic, magnetic anisotropy energy and optical properties of MnCrP half-Heusler alloy

In this current research work, the electronic, magnetic and optical properties of half Heusler alloy MnCrP are calculated and discussed within DFT framework. These calculations are done by using Wien2k code with Perdew–Burke–Ernzerhof Generalized Gradient Approximation and Tran-Blaha modified Becke-Johnson (TB-mBJ) exchange and correlation potentials. Band gap study along with density of states analysis divulge the magnetic nature of MnCrP. The magnetic moments with PBE-GGA and TB-mBJ are 4.426μB and 4.4542μB respectively. It shows the suitability of this material in spintronic device fabrications. The magnetic anisotropy energy of this half Heusler is also determined by the difference of energies in easy and hard magnetization directions. Several optical parameters are calculated, including dielectric constants, absorption parameter, refractive indices, reflectivity, extinction coefficient, energy loss function and conductivity. The imaginary part of the dielectric constant also predicts that the compound MnCrP is optically metallic and suitable for sensor application and optoelectronic device.

Effect of 5d state-based full-Heusler alloys on the structural, electronic and magnetic properties of new half metallic ferromagnetism

First-principles calculations of structural, elastic, electronic and magnetic properties of full-Heusler Ir2HfB, Ir2HfAl and Ir2HfGa have been realized by full-potential linearized augmented plane wave (FP-LAPW) method implemented inWIEN2K code. The Perdew–Burke–Ernzerh of generalized gradient approximation (PBE-GGA) carried out the computation of different parameters to describe elastic and structural properties. The calculation of structural properties revealed that the three alloys are stable in cubic AlCu2Mn-type structure in ferromagnetic state. The elastic constants calculation shows the three alloys satisfy the stability criteria. Indeed, the calculated spin-polarized electronic band structure and density of states using generalized gradient approximation (GGA) show that Ir2HfZ (Z = B, Al, Ga) alloys have a metallic character. The influence of strong electronic correlation has been considered in GGA+Uand mBJ-GGA+U approximations that allows for improving the width of the band gap. The calculations carried out with GGA+U and mBJ-GGA+U show that Ir2HfAl and Ir2HfGa have a half-metallic behavior; however, Ir2HfB has a near half-metallic character. The calculated magnetic moments of Ir2HfB, Ir2HfAl and Ir2HfGa in a regular cubic structure with GGA+U and mBJ-GGA+U equal 1μB. With mBJ-GGA+U, the spin polarization values are 100% for Ir2HfAl, Ir2HfGa and 99.90% for Ir2HfBto be applicable for spintronics.

Pressure-Induced Intermetallic Charge Transfer and Semiconductor-Metal Transition in Two-Dimensional AgRuO 3

Pressure-Induced Intermetallic Charge Transfer and Semiconductor-Metal Transition in Two-Dimensional AgRuO ₃

Electronic structure, magnetic, and thermoelectric properties of BaMn2As2 compound: a first-principles study

We report the magnetic stability, antiferromagnetic ordering, electronic, magnetic, and thermoelectric properties of BaMn2As2 employing the full-potential linearized augmented-plane wave method under the framework of density functional theory. The exchange-correlation energy was treated using the Perdew–Burke–Ernzerhof generalized gradient approximation (PBE-GGA) and GGA plus Hubbard U parameter method. From structural relaxation, we reveal that antiferromagnetic (A-AFM) state is more appropriate for BaMn2As2 than other known configurations. Under electronic properties, BaMn2As2 shows metallic nature in paramagnetic (PM) and antiferromagnetic phase (AFM). Further, the decrease in electrical conductivity over the entire temperature range characterize the metallic nature of BaMn2As2. The electronic band structure calculation demonstrates that Mn-3d and As-4p orbital hybridization are essential for the band gap formation, suggesting BaMn2As2, a hybridization-gap semiconductor. The total magnetic moment of BaMn2As2 in ferromagnetic phase is ~9.54 μB, with a major contribution from Mn atom. In thermoelectric, we obtain a negative Seebeck coefficient (S), n-type electrical conductivity, and a maximum ZT value of 0.40. Our study suggests BaMn2As2 as a novel candidate for spintronics and waste heat management.

FIRST-PRINCIPLES SIMULATION: STUDY OF THE STRUCTURAL, ELECTRONIC, MECHANICAL AND OPTICAL PROPERTIES OF DISULFIDE XS2 (X=Ta, Ti) COMPOUNDS FOR OPTOELECTRONIC APPLICATIONS

First-principles simulation has been performed to investigate the structural, electronic and optical properties of two disulfide compounds, i.e. [Formula: see text]S2 ([Formula: see text], Ti). The properties are examined through the density functional theory (DFT) with the implementation of Cambridge series total energy package (CASTEP) code. As regards, the structural and electronic analyses are done by Perdew–Burke–Ernzerhof-generalized gradient approximation (PBE-GGA) and hybrid Heyd–Scuseria–Ernzerhof (HSE06) functional and their results are compared herewith. The values of lattice parameters obtained through geometry optimization for TaS2 with GGA and HSE06 are [Formula: see text][Formula: see text]Å and [Formula: see text][Formula: see text]Å and [Formula: see text][Formula: see text]Å and [Formula: see text][Formula: see text]Å, respectively, while for TiS2 these parameters are found as [Formula: see text][Formula: see text]Å and [Formula: see text][Formula: see text]Å. These values are found in agreement with the experimental values. The electronic band structure, as well as density of states (DOS) of these structures, show their semiconducting nature with the direct bandgap of 1.9[Formula: see text]eV (PBE-GGA) and 2.05[Formula: see text]eV (HSE06) for TaS2 and 0.09[Formula: see text]eV (PBE-GGA) and 0.13[Formula: see text]eV (HSE06) for TiS2. The mechanical study of these compounds also has been anticipated using Voigt–Reuss–Hill approximation under the pressure range 0–30[Formula: see text]GPa to show their stability by calculating the elastic parameters, i.e. Young’s modulus, bulk and shear modulus, Poisson’s ratio, Pugh’s ratio and anisotropic factor. The analysis of optical properties divulges that TiS2 material possesses maximum absorptivity in the UV range of incident photon’s energy with minimum energy loss and decrease in reflectivity. Our comprehensive study about the considered compounds delineates them as potential candidates for technological applications in optoelectronic devices.

Opto-electronic, and thermoelectric properties of chalcopyrite compounds HgGa2X4(X = S, Se) for solar cell applications

The ab-initio method has been applied to explore the chalcopyrite compounds HgGa2X4 (X = S, Se) structural, optoelectronics, and thermoelectric characteristics. We attained the optimized parameters of lattice constant by employing Perdew–Burke–Ernzerhof generalized gradient approximation (PBEsol-GGA) and computed the values are approximately equal to experimental values. To calculate accurate bandgap values of both compounds, we used Trans along with Bhala reformed Becke and Johnson (TB-mBJ). Remarkably, both HgGa2X4 (X = S, Se) compounds yield a direct bandgap nature, having calculated values 2.80 eV and 2.30 eV, respectively, which are accurately comparable to experimental values. It also observed that the strong optical absorption is below 3.0 eV, which made both compounds favorable for solar cell device applications. In last, we make a detailed investigation of thermoelectric characteristics in terms of electric and thermal conductivity, power factor, and figure of merit (ZT) with the help of the BoltzTrap code. To check the material’s thermal stability, we accomplished the thermal parameters against temperatures.