Augmented Plane Wave Method Research Articles

Enhanced Sensitivity of Magneto-Optical Surface Plasmon Resonance in the FeCu Superlattices

We demonstrated the sensitivity enhancement for magneto-optical surface plasmon resonance (MOSPR) using noble/ferromagnetic metals multilayers. The proposed structure is based on the Kretschmann configuration in the transverse magneto-optical Kerr effect (TMOKE) methods with the FeCu superlattices (SLs) as magneto-plasmonic materials and gelatin as biomolecules analyte. The dielectric constants of the FeCu SLs are taken from first principles calculation, which is performed by using a full-potential linearized augmented plane wave (FLAPW) method. The important role of the hybridization process in optical transitions has been identified, and it can be modulated by adjusting the thickness of superlattices. The dependence of the reflectivity on the dielectric constant is performed by 4×4 transfer matrix methods. It is found that the minimum reflectivity directly influences the slope of angular spectra, with a maximum slope of TMOKE signal is 12.23/degree. The change in the gelatin’s refractive index results in TMOKE signal response, then the enhancement of the sensitivity of the MOSPR system can be shown.

A computational study of the structural and thermal conduct of MgCrH3 and MgFeH3 perovskite-type hydrides: FP-LAPW and BoltzTraP insight

The structural and thermal conduct of MgCrH3 and MgFeH3 perovskite have been investigated using the full-potential linearized augmented plane wave (FPLAPW) method and the BoltzTraP package, implemented in the Wien2k code. The calculations involved fitting the Murnaghan equation of state to the calculated total energy and atomic volume. The present analysis includes key groundstate parameters, such as the lattice parameter and its pressure derivative. Where the electrical conductivity of MgTMH3 (TM=Cr and Fe), the thermal conductivity, merit factor, and power factor were discussed in the range of 300-900 K. The obtained outcomes exhibit interesting results to make these compounds as promising materials for thermoelectrical applications.

Ab Initio Study of Li2FeSO Antiperovskite for Energy Storage

Density Functional Theory (DFT), in combination with the Wien2k software, is used to investigate the physical properties of Li3SO antiperovskite modified by atomic substitution with Fe. The objective is to understand, at the electronic and molecular levels, the electrochemical behavior of the doped material and to optimize its performance. This research was conducted using the Linearized Augmented Plane Waves (LAPW) method for analyzing the electronic structure of the (Li-Fe)3SO antiperovskite. The density of states analysis reveals an improvement in the lithium storage capacity of the doped material, as well as in the stability and charge transport capacity of the electrode. Additionally, the presence of absorbance peaks at energies close to the energy levels of the lithium battery may indicate a high lithium storage capacity in the material, making it promising for battery applications.

Ab initio investigations of the structure-stability, mechanical, electronic, thermodynamic and optical properties of Ti2FeAs Heusler alloy.

In this study, we employed density functional theory coupled with the full-potential linearized augmented plane-wave method (FP-LAPW) to investigate the structural, electronic, and magnetic properties of the Ti2FeAs alloy adopting the Hg2CuTi-type structure. Our findings demonstrate that all the examined structures exhibit ferromagnetic (FM) behaviour. By conducting electronic band structure calculations, we observed an energy gap of 0.739 eV for Ti2FeAs in the spin-down state and metallic intersections at the Fermi level in the spin-up state. These results suggest the half-metallic (HM) nature of Ti2FeAs, where the Ti-d and Fe-d electronic states play a significant role near the Fermi level. Additionally, the obtained total magnetic moments are consistent with the Slater-Pauling rule (Mtot = Ztot - 18), indicating 100% spin polarization for these compounds. To explore their optical properties, we employed the dielectric function to compute various optical parameters, including absorption spectra, energy-loss spectra, refractive index, reflectivity, and conductivity. Furthermore, various thermodynamic parameters were evaluated at different temperatures and pressures. The results obtained from the elastic parameters reveal the anisotropic and ductile nature of the Ti2FeAs compound. These findings suggest that Ti2FeAs has potential applications in temperature-tolerant devices and optoelectronic devices as a UV absorber.

Origin of the Magnetic-Optical Properties of Palladium Compounds, an Ab Intio Study

Abstract: The structural, magnetic, and magneto-optical properties of the PdM (M=Fe, Co, Ni) alloy are investigated using first-principles calculations with the exciting code. The study employs the full potential linearized augmented plane wave method (FP-LAPW) based on density functional theory (DFT). The exchange-correlation energy is described in the generalized gradient approximation developed by Perdew-Burke-Ernzerhof (PBE-GGA). The calculated lattice parameters are in good agreement with theoretical and experimental results. The magnetic properties reveal a ferromagnetic stability phase for all compounds. Additionally, the total (TDOS) and partial (PDOS) density of states, along with the band structure, indicate that PdM (M = Fe, Co, Ni) exhibits metallic behavior. The total and local magnetic moments are investigated. We conducted a study on the polar magneto-optical Kerr effect and calculated Kerr spectra. The microscopic origins of the peaks found in Kerr's angle are interpreted as interband transitions, primarily arising from the states (d to d) in the PdNi and (S to d) in the PdFe and PdCo alloys. Keywords: P-MOKE, DFT, GGA-PBE, Intermetallic.

Structural, Electronic, Magnetic and Optical properties of Sm doped ZnS: A First Principle Study

Wide band gap semiconductors have many applications in photo luminescence devices and optoelectronic devices. We have investigated the structural, magnetic and optical properties of pure ZnS and Sm doped ZnS using density functional theory and implemented first principle linearized augmented plane wave (LAPW) method. For exchange correlation potential energy, generalized gradient approximation (GGA), GGA+U (where U is Hubbard potential) and Trans and Blaha modiefied Becke-Johnson (TB-mBJ) approximations are used. ZnS is a wide band gap semiconductor material having experimental band gap ~ 3.54eV. In this study band gap of pure ZnS was calculated as 1.963eV, 2.124eV and 3.574eV by using GGA, GGA+U and TB-mBJ approximations. GGA+U approximation was used for spin polarized calculations of ZnS: Sm shows ferromagnetic (FM) behaviour of doped semiconductor with band gap is 2.75eV. Pure ZnS is isotropic material while after doping with Sm it becomes anisotropic material. Ultraviolet and visible radiations are absorbed in these materials hence they can have potential applications in optoelectronic devices.

Structural Analysis, Characterization, and First-Principles Calculations of Bismuth Tellurium Oxides, Bi6Te2O15

A single crystal of Bi6Te2O15 was obtained from the melt of the solid-state reaction of Bi2O3 and TeO3. Bi6Te2O15 crystallizes in the Pnma space group (No. 62) and exhibits a three-dimensional network structure with a =10.5831(12) Å, b = 22.694(3) Å, c = 5.3843(6) Å, α = β = γ = 90°, V = 1293.2(3) Å3, and Z = 4. The structure was determined using single-crystal X-ray diffraction. An asymmetric unit in the unit cell, Bi3Te1O7.5, uniquely composed of four Bi3+ sites, one Te6+ site, and nine O2− sites, was solved and refined. As a bulk phase, Bi6Te2O15 was also synthesized and characterized using powder X-ray diffraction (XRD), infrared (FT-IR) spectrometry, and the thermogravimetric analysis (TGA) method. Through bond valence sum (BVS) calculations from the single crystal structure, Bi and Te cations have +3 and +6 oxidation numbers, respectively. Each Bi3+ cation forms a square pyramidal structure with five O2− anions, and a single Te6+ cation forms a six-coordinated octahedral structure with O2− anions. Since the lone-pair electron (Lp) of the square pyramidal structure, [BiO5]7−, where the Bi+ cation occupies the center of the square base plane, exists in the opposite direction of the square plane, the asymmetric environments of all four Bi3+ cations were analyzed and explored by determining the local dipole moments. In addition, to determine the extent of bond strain and distortion in the unit cell, which is attributed to the asymmetric environments of the Bi3+ and Te6+ cations in Bi6Te2O15, bond strain index (BSI) and global instability index (GII) were also calculated. We also investigated the structural, electronic, and optical properties of the structure of Bi6Te2O15 using the full potential linear augmented plane wave (FP-LAPW) method and the density functional theory (DFT) with WIEN2k code. In order to study the ground state properties of Bi6Te2O15, the theoretical total energies were calculated as a function of reduced volumes and then fitted with the Birch–Murnaghan equation of state (EOS). The band gap energy within the modified Becke–Johnson potential with Tran–Blaha parameterization (TB-mBJ) revealed a value of 3.36 eV, which was higher than the experimental value of 3.29 eV. To explore the optical properties of Bi6Te2O15, the real and imaginary parts of the dielectric function, refraction index, optical absorption coefficient, reflectivity, the real part of the optical conductivity extinction function, and the energy loss function were also calculated.

Rare earth-based oxides double perovskites A2NiMnO6 (A= La and gd): Applications in magneto-caloric, photo-catalytic and thermoelectric devices

In this paper, we have conducted theoretical work on rare earth-based double perovskites namely, La2NiMnO6 and Gd2NiMnO6, using generalized gradient approximation (GGA) and GGA + U formulations within the full potential linearized augmented plane wave (FP-LAPW) method. It is revealed that using GGA + U computations instead of the conventional GGA method results in a reasonable widening of the band gaps and best fit with the previously explored experimental data with U = 1.5 eV. Further, the band gap values are increased with increasing the U values for the 3d states of Ni and Mn. Moreover, we found that these materials show high magnetic moment, high absorption in the visible and ultraviolet region, and high figure of merit (nearly one for Gd2NiMnO6 at room temperature), hence show their potential in multiple applications such as magneto-caloric, photo-catalytic, solar energy, and thermoelectric devices.

First-principles investigation of structural, electronic, and optical properties of cubic halide perovskite RbSrI3

In this article, the structural, electronic, and optical properties of lead-free cubic halide perovskite RbSrI3 are investigated by the first principles method that employs the density functional theory (DFT). This study implements the full potential linearized augmented plane wave (FP-LAPW) method with the generalized gradient approximation of Perdew-Burke-Ernzerhof (PBE-GGA) as the exchange-correlation potential. The structural stability of the compound is calculated using the Murnaghan equation of state, and the band structure calculations show the presence of a wide indirect bandgap of 3.32 eV. The optical response of the compound over the energy spectrum of 0–12 eV is studied and the compound exhibits good reflectance of 30.73 % at 7.66 eV and absorption of 112.45 × 104 cm−1 at 11.74 eV in the ultraviolet region. The values of reflectivity R(ω) and absorption coefficient α(ω) indicate that the compound shows potential in the fabrication of UV-related optoelectronic devices.

Electronic structure, optical and elastic properties of Si doped Strontium Selenide: A theoretical investigation

The structural, electronic, optical, and elastic properties of Silicon doped Strontium Selenide binary and ternary semiconductor alloys with the general form of Sr(1-x)SixSe, 0 ≤ x ≤ 1 in B1 and B3 phases have been figured adopting augmented plane wave plus local orbital methods within density functional theory, Structural properties summarize the crystal structure, relevant atomic positions, lattice constant, bulk modulus minimum energy E0 and minimum volume V0. Elastic constants conform to the structure stability of the B1 and B3 phases. Band gap is found to shift from indirect to direct and in some materials with initial direct band gap, the gap width increased which increased the range of applicability of these binary and ternary semiconductor compounds. Whereas optical properties which include the study of zero frequency limit of static dielectric constant ε0(ω) with its real and imaginary parts, static refractive index n(0), optical reflectivity (R), optical absorption coefficient (α), and loss function (L) studied comprehensively to get real electrical and optical properties of these materials and give semiconductor market best alternative candidate which shows its effectiveness in the visible, ultraviolet and infrared region of the electromagnetic spectrum. The obtained results were compared together and with the available experimental along with theoretical work on these binary and ternary Silicon doped Alkaline earth chalcogenides.

Exploring properties of organometallic double perovskite (CH3NH3)2AgInCl6: A novel material for energy conversion devices

Distinct types of materials are being explored for usage in thermoelectric (TE) and photovoltaic (PV) systems in order to alleviate the energy problem. In order to create nontoxic, more stable, and best-performance energy convergence devices, the state-of-the-art hybrid halide double perovskites (HHDPs) compound has been identified as a potential TE material and potential replacement for hazardous lead. We have proposed a new HHDP material (CH3NH[Formula: see text]AgInCl6 and performed its theoretical investigation via the full potential linear augmented plane wave (FP-LAPW) method. The computational results show that the studied compound exhibits a direct bandgap of 3.708[Formula: see text]eV and has exceptional PV characteristics in the ultraviolet (UV) region. The obtained thermodynamic (TD) characteristics confirm that the titled compound is thermally stable at various temperatures and pressures. At 300 K, the examined HHDP material has the highest ZT (=2.23) in the p-region. Materials with higher ZTe values are substantially more important for generating electrical energy through waste heat. The ZTe result validates the use of these materials in TE devices at ambient temperature. The parameters of this compound have been computed for the first time. This study identifies (CH3NH[Formula: see text]AgInCl6 as a novel HHDP compound. Through an in-depth exploration of its properties, this study offers valuable insight for further research with potential applications in clean energy systems.

An Ab-initio study on spin gapless semiconducting in novel quaternary heusler alloys RhCoVZ (Z = Al, Ga, and In): Insights into stability, electronic, magnetic, thermoelectric, and optical properties

The stability and half-metallic ferromagnetic properties of recently developed gapless semiconductor alloys, RhCoVZ (Z = Al, Ga, and In), were the subject of investigation in this research study. Three different non-equivalent structural configurations, namely type I, type II, and type III structures, have been examined. Among these compounds, Type I is characterized as the most stable phase in the ferromagnetic order, as opposed to the non-magnetic order. Through calculations of cohesive energies, formation energies, phonon dispersion curves, and elastic constants, we have demonstrated that RhCoVZ (Z = Al, Ga, and In) exhibits thermodynamic stability, as well as dynamic and mechanical. Using modified Becke-Johnson (mBJ) calculations, it has been revealed that RhCoVZ (Z = Al, Ga, and In) are spin gapless semiconductor half-metallic ferromagnets with an indirect bandgap. Additionally, it was observed that the electrons at the Fermi level (EF) are entirely spin-polarized. The total magnetic moment in all three compounds was determined to be an integer value of 2.00 µB per formula, in accordance with the Slater-Pauling rule (Mt = Zt - 24). All the calculations in this study were performed using density functional theory (DFT) based on the full-potential linearized augmented plane wave (FP-LAPW) method, which was implemented in the WIEN2k code. The effective mass of electrons/holes is (0.167/0.385) for RhCoVAl, (0.454/0.322) for RhCoVGa, and (0.604/0.242) for RhCoVIn. The thermoelectric properties of the three compounds were explored using the semi-classical Boltzmann transport theory. It was discovered that all three compounds exhibit high power factors and high Seebeck coefficients, with values reaching up to 1.5 mV/K for RhCoVAl and 1.25 mV/K for RhCoVGa. Based on the results, the highest observed ZT values for RhCoVZ (Z = Al, Ga, and In) are 0.95, 0.97, and 0.93, respectively. The study's findings indicate that these compounds possess stable characteristics, making them promising candidates for various device applications in fields like spintronics, thermoelectricity, shape memory, and spin filters. Furthermore, the investigation of their optical properties, including the dielectric function and absorption coefficient, suggests potential implications for optoelectronic applications. Overall, these materials exhibit diverse and valuable properties, opening up exciting opportunities for future technological advancements in multiple domains.

Structural, Elastic, Electronic, and Magnetic Properties of Nd‐Doped NaScGe Half‐Heusler Compound by Ab‐Initio Method

AbstractA comprehensive investigation is conducted on the electronic structure and magnetic properties of half‐Heusler NaScGe, which is doped with a rare earth element Nd with different concentrations. The Heusler Na1‐xNdxScGe (where x = 0, 0.25, 0.75, and 1) compounds are thoroughly investigated. The examination encompassed structural, elastic, magnetic, and electronic characteristics using the full potential linearized augmented plane wave (FP‐LAPW) method. Generalized gradient approximation (GGA) is used to calculate the structural parameters and electronic characteristics. The equilibrium lattice constant and band gap of half‐Heusler NaScGe are found to be in good accord with other data. The density of states (DOS) investigation has revealed a semiconductor behavior of half‐Heusler NaScGe and half‐metallic ferromagnetic properties of quaternary‐Heusler Na0.75Nd0.25ScGe, characterized by a moderate band gap in minority spin channel. In addition, the DOS analysis has shown that both ternary half‐Heusler NdScGe and QH Na0.25Nd0.75ScGe compounds have exhibited metallic ferromagnetic activity. The work has introduced a novel approach for producing half metals from the semiconductor half‐Heusler NaScGe. Quaternary‐Heusler Na0.75Nd0.25ScGe is identified as a promising material for applications spintronic.

Variation of cation-ligands XAl2Ge2 (X = Pr, Nd, Gd, Tb) compounds by employing density functional theory

The present report aims to examine detailed Cationic ligands replacement for XAl2Ge2 (X = Pr, Nd, Gd, Tb) compounds by employing the density functional theory (DFT) within full-potential linear augmented plane wave (FP LAPW) method. For the structural determination, the generalized gradient (PBE-GGA) approximation has been used to get theoretical reliable and analogous results with the available experimental data. We have further established that the ferromagnetic phase is more stable and suitable for calculation of the magnetic properties. The two approximations namely (PBE-GGA and GGA+U) are used for the investigation of band structures. The band structures along with density of state (DOS) plots approve the metallic character of XAl2Ge2. There exists a strong hybridization between (Pr, Nd, Gd, Tb) f and (Al, Ge) s, p states. Also, the examination of magnetic properties confirms a strong ferromagnetism in XAl2Ge2 compounds.

Electronic structure, optical properties and high thermoelectric figure of merit in iron phthalocyanine polymer: FP-LAPW comparative studies

The comparative study of optoelectronic and thermoelectric properties of Iron phthalocyanine polymer, FePc, has been performed using the full-potential linearized augmented plane wave (FP-LAPW) method. The results show that the band gap of FePc is 2.039 eV with two deep trap bands. Optical spectra such as the real and imaginary parts of the dielectric function, reflectivity, electron energy loss spectroscopy, refractive index, extinction, and absorption coefficients are calculated and the main peaks are compared with the available experimental data. Calculated optical spectra are in good agreement with the experimental data of diethylamine and triethylamine polymers. The maximum values of 2190.2 μVK−1 and 1.02 are obtained for the Seebeck coefficient and the figure of merit ZT at 300 K for the chemical potentials near the Fermi level, respectively. The results show that FePc polymer is a good candidate for optoelectronic device applications.

Ab-Initio Investigation into the Physical Characteristics of CuInSe2 and CuInTe2 Compounds

In this study, an analysis of chalcopyrite compounds CuInTe2 and CuInTe2 is presented, with a focus on their electronic, structural, optical, and thermal properties. The full-potential linearized augmented plane wave (FP-LAPW) method is employed for the investigation of these properties, based on a first-principles approach rooted in density functional theory (DFT). Two distinct approximations for the exchange and correlation potential, namely the WC-GGA and mBJ-GGA approximations, are considered in our calculations to ensure a robust and accurate examination of the materials under scrutiny. The findings obtained closely align with previously established theoretical and experimental data, thereby validating the reliability of our computational methodology. It is noteworthy that a novel dimension is introduced by this study, as the influence of both pressure and temperature on the thermal parameters of CuInTe2 and CuInTe2 compounds is explored. This facet of the research is distinguished by its innovative nature, as there is no prior record, to the best of our knowledge, of a similar analysis in the existing literature. The thermal properties are deemed of paramount significance, particularly in the context of crystal growth process optimization and the prediction of performance under extreme thermodynamic conditions.

Study of optoelectronics and magnetic properties of GdCrWO6 oxide by ab initio calculations

Using first-principle calculations within the framework of density functional theory (DFT), the full-potential linearized augmented plane-wave (FP-LAPW) method have been performed to investigate structural, electronic, magnetic and optical properties of the aeschynite type GdCrWO6 oxide within both generalized gradient approximation (GGA) and modified Becke Johnson potential (TB-mBJ). GdCrWO6 forms the polar crystal structure (space group Pna21 (#33)) due to the cation ordering of W6+ and Cr3+. Our calculations reveal that the compound GdCrWO6 is a semiconductor by the GGA-PBE and TB-mBJ approximations. The magnetic moment of each magnetic atom is found for two approximations. The imaginary part, real part and the optical conductivity of dielectric function of the compound GdCrWO6 are found by TB-mBJ. GdCrWO6 exhibits a strong absorption coefficient in the ultraviolet region.

Study of structural, elastic, electronic, optical and magnetic properties of Heusler Mn2NiAl: Ab initio calculations

In this paper, we will investigate the structural, electronic, mechanical, magnetic and optical properties of Heusler Mn2NiAl (MNA) compound using the Perdew–Burke–Ernzerhof generalized gradient approximation (PBE-GGA) of the full potential linearized augmented plane-wave method for exchange and use correlations, modified Becke–Johnson and GGA+U Hubbard parameter. The calculated band structure (BS) and density of states (DOS) of MNA showed a metallic (GGA), nearly half-metallic (mBJ) and half metallic (GGA+U) behavior. Moreover, the magnetic computed magnetic moments by GGA+U are higher compared to GGA and mBJ results. Bulk modulus, shear modulus, Voigt and Reuss polycrystalline elastic modulus, Debye temperature, sound velocities, the melting temperatures, [Formula: see text] ratio, Young’s modulus and Poisson’s ratio were obtained. The elastic anisotropy of MNA alloy was analyzed using 2D and 3D figures of directional dependence of Poisson’s ratio, shear modulus, linear compressibility and Young’s modulus. Studies have shown that the Heusler material MNA has magnetic and anisotropic properties and is mechanically stable.

Modeling and simulation of multifaceted properties of X2NaIO6 (X = Ca and Sr) double perovskite oxides for advanced technological applications.

In this study, the authors have investigated the structural, optoelectronic, thermoelectric, and thermodynamic properties of Ca2NaIO6 and Sr2NaIO6 double perovskite oxides. Both materials exhibit semiconductor behavior with direct band gaps (Eg) of 0.353eV and 0.263eV, respectively. Optical parameters like absorption coefficient α(ω), reflectivity R(ω), dielectric constants, and refractive index have been calculated. The most notable absorption peaks are identified at 5.52eV (equal to 108.33 × 104cm-1) in the case of Ca2NaIO6 and at 11.16eV (equivalent to 118.17 × 104cm-1) for Sr2NaIO6. These findings suggest a promising outlook for applications in optoelectronics. Moreover, their commendably low thermal conductivity and a high figure of merit, particularly at low temperatures (100K), indicate their effectiveness as thermoelectric materials. This analysis underscores that these materials hold potential as suitable candidates for n-type doping, making them well-suited for use in thermoelectric devices. Studying thermal properties, including thermal expansion, bulk modulus, acoustic Debye temperature, entropy, and heat capacity, contributes to understanding the materials' thermodynamic stability. The titled materials are dynamically stable. The analysis of these double perovskite materials highlights their potential across various technological applications due to their advantageous structural, electronic, optical, and transport properties, offering new possibilities in material science and technology development. The study utilized the full potential linearized augmented plane wave (FP-LAPW) method in conjunction with density functional theory within the WIEN2k simulation code. This approach is widely recognized as one of the most dependable methods for evaluating the photovoltaic characteristics of semiconducting perovskites. The thermoelectric properties were ascertained using the rigid band approach and the constant scattering time approximation, both implemented in the BoltzTraP computational code.

Exploring structural, electronic, magnetic, and optical response of GaN-X (X=Sr, ba, cs, mg) materials for optoelectronic applications

This research explores the structural, electronic, magnetic, and optical properties of GaN-X (X = Sr, Ba, Cs, Mg) materials. First principle calculations based on full potential linearized augmented plane wave (FP-LAPW) method is executed in Wien2k code. PBE-GGA approximation is used to approximate exchange-correlation functional. Sr 3d-states, Ba 5p-states, Cs 5p-states, and Mg 2p-states help in improving electronic properties. The magnetic character of the proposed materials is revealed with net magnetic moment values of, 2.9639 μB, 2.3316 μB, 3.4179 μB, and 3.1697 μB, respectively. Optical absorption shows blueshift for Ba@GaN and Mg@GaN while Sr@GaN and Cs@GaN spectra show redshift. Absorption and conductivity are enhanced in the UV region, along with decrease in reflectivity. Optical response of proposed materials illustrate to make use of these materials for production of high energy UV optoelectronics, photonics, memory, spintronics and photovoltaic devices.