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In this work, the WIEN2k computer code was used to investigate the structural, elastic, electronic, magnetic, optical, thermoelectric, and dynamic properties of the CoCrTe half-Heusler (HH) compound. The Full-Potential Linearized Augmented Plane Wave method and Density Functional Theory were both used in this work. To further understand the electronic band gap, we used the modified Becke Johnson exchange–correlation functional method. We investigated the CoCrTe HH compound's electronic characteristics using density of states plots and band structure plots. By calculating magnetic moments and observing the behavior of spin-polarized electronic states, we also investigated the magnetic properties. Additionally, the CoCrTe HH compound's elastic properties were identified. These characteristics, including stiffness, resilience, and overall stability, offer crucial information about how the material reacts to mechanical deformation. Properties studied emphasized that the compound is metallic, and it appears as a good thermoelectric material. Finally, the compound's dynamic properties show that it is dynamically stable as well as mechanically. [ABSTRACT FROM AUTHOR]

The structural, elastic, electronic, magnetic, thermoelectric, and dynamic properties of the CoCrSe half-Heusler compound were examined using the WIEN2k code. Calculations were carried out in this work using the full-potential linearized augmented plane-wave (FP-LAPW) approach and density functional theory (DFT). We used modified Becke–Johnson (mBJ) exchange–correlation functional to improve the electronic energy bandgap. We studied different electronic properties of the CoCrSe compound, including density of states (DOS) and band structure plots. We also investigated the magnetic characteristics by computing magnetic moments and examining the behavior of spin-polarized electronic states. In addition, the elastic characteristics of the CoCrSe compound were determined. These properties, such as stiffness, resilience, and general stability, provide vital insights into the material’s response to mechanical deformation. The calculated elastic constants indicate that CoCrSe it is mechanically stable, brittle, and anisotropic. On the other hand, the compound is dynamically stable. Finally, we also check the thermoelectric properties. [ABSTRACT FROM AUTHOR]

The present article has utilized the WIEN2k computational code to examine the structural, elastic, electronic, magnetic, thermoelectric, and dynamic aspects of the CoCrS Half-Heusler (HH) compound. In this work, calculations have been performed by utilizing the full-potential linearized augmented plane wave method using density functional theory. The electronic bandgap was better interpreted by using the modified Becke–Johnson exchange–correlation functional. We evaluated various electronic properties of the CoCrS HH compound, including band structure plots and density of states. Furthermore, we examined the magnetic characteristics through the computation of magnetic moments and the examination of the spin-polarized electronic state behavior. We also determined the elastic properties of the CoCrS HH compound. These properties, which include stiffness, resilience, and general stability, provide important information about how the material responds to mechanical deformation. Moreover, we explored the electronic structure and found that type 5 of CoCrS exhibits a metallic behavior. In addition, we examined the compound's thermoelectric properties. Finally, the dynamical properties indicate that type 5 of CoCrS is dynamically stable. [ABSTRACT FROM AUTHOR]

The structural, mechanical, and electronic properties of rubidium iodide (RbI) have been extensively investigated utilizing the generalized gradient approximation (GGA) and the full-potential linearized augmented plane wave (FP-LAPW) approach. The potential was roughly calculated using a modified Becke–Johnson (mBJ) approximation, which increased the precision of the electronic properties. In this study, RbI is analyzed in a wide range of crystal structures, including topologies like rock salt (RS), CsCl, zinc blende (ZB), NiAs, and wurtzite (WZ), among others. Our research shows a strong relationship between the material's physical properties and the conclusions drawn from both theoretical and experimental studies. Significantly, our results show that the RS form corresponds to RbI's ground state. All the aforementioned topologies display wide-bandgap semiconductor capabilities, according to further examination of their electronic band structures. Notwithstanding these findings, it was discovered that RbI has a poor fracture resistance due to its low bulk modulus. Born's stability analysis has shown that RbI is stable in the RS, CsCl, ZB, NiAs, and WZ structures. All RbI structures were discovered to have ionic bonding and to be ductile, and every stabilized system displayed anisotropic stability. Using the Cauchy pressure and Poisson's ratio, the stiffness of the systems was evaluated, with the RS structure proving to be the stiffest. Overall, the findings illuminate the physical properties of RbI, providing valuable insights that could facilitate the creation and refinement of novel materials possessing desirable characteristics. [ABSTRACT FROM AUTHOR]

The structural parameters, electronic, optical, and elastic properties of Niobium Carbide (NbC) compound within four different structures: rock-salt (RS), wurtzite (WZ), cesium chloride (CsCl), and Nickel Arsenide (NiAs) are examined using the Full-Potential Linearized-Augmented Plane Wave (FP-LAPW). The exchange–correlation potential (VXC) has been treated by Perdew, Burke, and Ernzerhof's generalized gradient approximation (PBE-GGA) when structural properties, transition pressure, and elastic properties are estimated. For electronic properties, in addition to (PBE-GGA), the modified Becke–Johnson (mBJ-GGA) was used for increased accuracy. Present results show that the RS of NbC is the most stable among the four examined structures with the lowest equilibrium energy. The calculated lattice constants are in good agreement with the former calculations. The elasticity and the formation energy calculations show that NbC is stable within the four studied structures. The electronic band structure calculations of NbC show that it has a metallic nature in the four considered structures. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Metal fluorides are ionic compounds with intriguing properties and a wide range of industrial and technological applications. In this paper, we present the results of an extensive first-principles study of the electronic band structure of nineteen mono-, di-, and tri-fluorides. Four approaches are employed in this study: LDA, pseudopotential and all-electron modified Becke–Johnson (mBJLDA@PP and mBJLDA@AE) potentials, and Yukawa Screened Hybrid Functional (YS-PBE0). The mBJLDA and YS-PBE0 band gaps are in good overall agreement with the available G 0 W 0 results and experimental data, which ensures the reliability of the provided predictions for systems where accurate band gaps are lacking. The LDA and YS-PBE0 upper valence band (UVB) widths are very close to each other, and these results are, in general, slightly smaller than the G 0 W 0 results and experimental data. It is shown that the band gap and UVB width vary with F F distance, and distinct trends are identified. The LDA density of states of the UVB for the alkali and alkaline-earth fluorides are analyzed and compared to the available XPS and XES spectra. It is found that the LDA approach provides accurate results for peak intensities as well as satellite peak positions relative to the main peak. A strong correlation is demonstrated between the adopted crystal structures of the considered fluorides and their bond ionicity. • Four approaches are used to study the electronic structure of 19 metal-fluorides. • For several of the fluorides considered, reliable predictions have been made. • Band gaps and upper valence band widths are found to exhibit clear trends. • The bonding mechanisms of fluorides are discussed in detail. • A correlation is established between bond ionicity and crystal structure. [ABSTRACT FROM AUTHOR]

The equilibrium structural parameters, electronic, magnetic and elastic properties of the inverse Zr 2 RhGa and normal Co 2 TiSn Full-Heusler compounds have been studied using density-functional theory (DFT) and full-potential linearized augmented plane-wave (FP-LAPW) method as implemented in the WIEN2k package. The Generalized Gradient Approximation (GGA) has been used for the exchange-correlation potential (V xc) to compute the equilibrium structural parameters; lattice constant (a), bulk modulus (B) and bulk modulus pressure derivative (B′). In addition to the GGA approach, the modified Becke Johnson (mBJ) scheme has been used to calculate the band gap energies. The normal Heusler Co 2 TiSn compound and the inverse Heusler Zr 2 RhGa compound within GGA and mBJ approaches are found to have a half-metallic behavior, with an indirect energy gap in the spin down configuration. The calculated total magnetic moments for both compounds are to some extent compatible with the available experimental and theoretical results. Elastic constants and their related properties were obtained by using the IRelast package. These compounds are mechanically stable. The elastic constants satisfy the Born mechanical stability criteria. B/S ratio shows that the normal Co 2 TiSn has a brittle nature, while the inverse Zr 2 RhGa has a ductile nature; Poisson's ratio (ν) values show that both compounds have an ionic bond nature. • Normal Co 2 TiSn and inverse Zr 2 RhGa compounds possess half-metallic behavior. • Normal Co 2 TiSn and inverse Zr 2 RhGa compounds have an indirect energy gaps. • Normal Full Heusler Co 2 TiSn and inverse Full Heusler Zr 2 RhGa are mechanically stable. • B/S results show that normal Co 2 TiSn is brittle, while inverse Zr 2 RhGa is ductile. • Poisson's ratio (ν) values show that both compounds have ionic bonds. [ABSTRACT FROM AUTHOR]

The structural, mechanical, electronic and optical properties of SrTMO3 (TM = Rh, Zr) compounds are investigated by using first principle calculations based on density functional theory (DFT). The exchange-correlation potential was treated with the generalized gradient approximation (GGA) for the structural properties. Moreover, the modified Becke-Johnson (mBJ) approximation was also employed for the electronic properties. The calculated lattice constants are in good agreement with the available experimental and theoretical results. The elastic constants and their derived moduli reveal that SrRhO3 is ductile and SrZrO3 is brittle in nature. The band structure and the density of states calculations with mBJ-GGA predict a metallic nature for SrRhO3 and an insulating behavior for SrZrO3. The optical properties reveal that both SrRhO3 and SrZrO3 are suitable as wave reflectance compounds in the whole spectrum for SrRhO3 and in the far ultraviolet region (FUV) for SrZrO3. [ABSTRACT FROM AUTHOR]

Both electronic as well as magnetic characteristics of Co1-xFexMnSb (x = 0, 0.25, 0.50, 0.75, 1) composite have been studied by employing the first principle (FP) study. The FP calculation was attained using the density functional theory (DFT). The exchange–correlation term has been examined inside the generalized gradient approximation (GGA), as implemented in the Wien2k code. According to predictions, the type 3 structure of atoms will be the tremendous, optimum, and have the smallest amount of energy. The formation energy of CoMnSb and FeMnSb was minimum so it demonstrates that these alloys are optimized. CoMnSb and FeMnSb are half-metallic (HM) having the value of magnetic moment 3µB and 2µB, respectively in good agreement with the Slater-Pauling rule. These results suggest that the Mn atoms are the primary source of the magnetic moment. The values of elastic constants were determined by the crystal structure's symmetry. Additionally, the bulk modulus B, shear modulus G, Young's modulus E, as well as Poisson's ratio v have been determined using the Voigt-Reuss-Hill (VRH) method. Both examined compounds, CoMnSb and FeMnSb, have computed B/G ratios higher as compared to 1.75, indicating that these alloys are malleable. [ABSTRACT FROM AUTHOR]

The temperature dependence of the sound absorption coefficient at critical composition and above critical temperature Tc for the binary mixture nitroethane-isooctane at 5, 7, 10, 15, 21, and 25 MHz frequencies (f) is investigated. The frequency dependence of the absorption coefficient (α) for the same critical binary mixture at different temperatures above critical temperature is studied. In addition, the linear relation of the sound absorption coefficient at critical point ( α c ) / f 2 versus f−1.06 showed an excellent agreement with the dynamic scaling theory of Ferrell and Bhattacharjee, Physical Review A 31, 1788 (1985). The experimental values of ( α f − 2 α c f − 2 ) for nitroethane-isooctane binary mixture are plotted as a function of reduced frequency Ω and it showed a good agreement with the theoretical scaling function F(Ω). [ABSTRACT FROM AUTHOR]

The structural, elastic, electronic, magnetic, and thermoelectric properties of MgEu2X4 (X = S and Se) spinel compounds are investigated computationally. Calculations are performed using the full‐potential linearized augmented plane wave (FP‐LAPW) method within the Perdew, Burke, and Ernzerhof generalized gradient approximation (PBE‐GGA), GGA + U, and modified Becke–Johnson (mBJ‐GGA) approximations. The band structure and density of states results from the three exchange‐correlation approximation methods (mBJ, GGA + U, and PBE) show that these spinel compounds are fully spin‐polarized. Also, they possess a half‐metallic character in the spin‐down channel with a direct bandgap (Γ–Γ) of about 3.44, 2.712, and 2.472 eV for MgEu2S4 and 2.89, 2.285, and 2.017 eV for MgEu2Se4, respectively. The formation of both compounds is energetically favorable based on the results of the total energy and cohesive energy calculations. Furthermore, the two compounds are chemically and mechanically stable, as concluded from cohesive energy and elastic calculations. The elastic calculations reveal that both spinel compounds are ductile materials. The ionic bonds are predominant. The quasi‐harmonic model has also been used to investigate the influences of temperature and pressure on thermal characteristics. The thermoelectric behavior is studied using the BoltzTraP code. Both systems show good thermoelectric properties for the spin‐down channel. [ABSTRACT FROM AUTHOR]

The magnetic, electronic and optical properties of alloys for selected concentrations ( x = 0, 0.25, 0.50, 0.75 and 1.0) were investigated by means of density functional theory (DFT) calculations utilizing full potential linearized augmented plane wave (FP-LAPW) method. It was found that doping the alloy with rare-earth ions like Eu generates the nonstoichiometric and changes its original behavior from half ferromagnetic material to a metallic one. In addition, the total magnetic moment was found to increase with increasing dopant concentration with maximum local magnetic contributions on the Eu-sites. The optical dielectric functions as well as their static value for all the above alloys were also investigated. Moreover, the absorption coefficient, reflectivity and refractive indices were calculated. All the optical calculations were found to agree well with the band structure calculations when determining the alloys' half-metallic behavior. Finally, the nonstoichiometric metallic compounds found in this series might be useful in the flat panel industry as potential phosphors. [ABSTRACT FROM AUTHOR]