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In this paper, we investigated the magnetic stability, structural, electronic, and elastic properties of Os2YAl, (Y = Cr, Mn, and Fe) using the linearly augmented plane wave method based on the functional theory of the density implemented in the Wien2k Code. Our calculations showed that the three Os2YAl, (Y = Cr, Mn, and Fe) alloys are energetically more stable in the ferromagnetic state in the Cu2MnAl type structure at the equilibrium volume. The cohesive energy confirms the structural stability of all compounds. The spin-polarized electronic structures of the three materials exhibit a metallic character, which results from the fact that the (Cr, Fe, and, Mn)-3d states are dominant at the Fermi level. The main factors governing the electronic properties are the (Cr, Fe, and, Mn)-3d, and Os–5d hybrid states. The elastic constants are calculated and the conditions of the criterion of mechanical stability are checked. Debye's temperature was estimated from the average speed of sound. [ABSTRACT FROM AUTHOR]

In this paper, we studied the magnetic stability, structural, elastic and electronic properties of Ir2FeAl full Heusler compound in the regular phase (Cu2MnAl, prototype L2 1) , by using the first principle of density functional theory, with the generalized approximation of the GGA gradient. We found that the ferromagnetic state of Ir2FeAl is more stable than the nonmagnetic configuration at their lattice parameters equilibrium. This result was confirmed by the calculation of the cohesive energy. The stability is asserted by the elastic constants and the conditions of the mechanical stability criterion. The band structure and the calculated densities of states (DOS) of this alloy show a semi-metallic behavior. The ferromagnetic performance of Ir2FeAl is confirmed by the total magnetic moment of 4.28 μ B , where its major contribution comes from Fe atoms. We estimated the Debye temperature of Ir2FeAl from the average speed of sound. This is the first quantitative theoretical prediction of the elastic properties of the Ir2FeAl compound, and it still awaits experimental confirmation. [ABSTRACT FROM AUTHOR]

In 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. [ABSTRACT FROM AUTHOR]

Using the first-principle methods based on the density functional theory, in order to study structural, elastic, and electronic properties of MAX phases M 2 CdC with M = (Sc, V, and Nb). The calculated formation energies revealed that these compounds are thermodynamically stable in the hexagonal MAX phase. The stability is affirmed by the elastic constants and the conditions of the mechanical stability criterion. The calculated electron band structures and the density of states imply that the chemical bond in three compounds are a combination of covalent, ionic, and metallic nature. The main factors governing the electronic properties are the hybrid states M-d, Cd-p, and C-p, and the bond (p-d) stabilizes the structure. Fermi's surface characteristics have been studied for the first time. Based on the total energy, we conclude that as continue to increase Sc-V, Nb, the compressibility modulus decreases. At the same time, it gives a stabilization of the hexagonal structure and increases the metal support. [ABSTRACT FROM AUTHOR]

The structural, elastic, electronic, magnetic, and thermodynamic properties of the all-Heusler Pd2CrGe alloy are investigated using the full-potential linearized augmented plane wave method based on density functional theory. The results show that the Pd2CrGe compound is more stable in the Cu2MnAl type structure compared to the Hg2CuTi type and more stable in the ferromagnetic (FM) state than in the paramagnetic (PM) state. The calculated cohesive energies confirm this result. The structural, electronic, magnetism, and elastics properties, were calculated and analyzed in the Cu2MnAl type in the ferromagnetic ground state. The calculated lattice constant is in good agreement with the available structural data. The band structure and the calculated densities of states (DOS) of this alloy show a metallic behavior. This result was demonstrated by three approaches (GGA, GGA + U, and TB-mBJ). Near the Fermi level, the energy is mainly occupied by Pd-4d and Cr-3d electrons. The calculated total magnetic moment of 3.62 µB is not in agreement with the value of 6 µB of the Slater–Pauling rule. The calculated values of the elastic constants follow the criteria of mechanical stability. The mechanical results show a ductile character. Using the quasi-harmonic Debye model has been employed to study the pressure and temperature-dependent thermodynamic properties of Pd2CrGe. [ABSTRACT FROM AUTHOR]

In this work, we have studied the structural, electronic, elastic, and thermodynamic properties of the new Max phase's class Mn2SiC1, Mn3SiC2 and Mn4SiC3 (Mnn+1SiCn with n = 1, 2 and 3), using the linearly augmented plane wave method (FP-LAPW) based on density functional theory. The exchange-correlation potential is treated with the local density approximation LSDA. The formation energies calculated for all compounds showed that these compounds are thermodynamically stable. We found that the ferromagnetic (FM) configuration is more stable than the non-magnetic (NM) one, at their lattice parameters for all three compounds. Cohesive energy confirms the structural stability of all structures. The total magnetic moment increases with an increasing value of n. The band structure indicates that the three materials are electrically conductive. For the density of state, we see that there is no gap for these three materials; they exhibit a metallic nature which results from the fact that the Mn-3d states are dominant at the Fermi level. The peak of hybridization of the Mn–3d, and C–2p states leads to a strong covalent bond than that between the Mn–3d and Si–3p states in the low energy domain. 3p electrons in silicon elements can effectively alter the covalence and iconicity of bonds that govern compressibility, ductility, and even superconducting properties. The chemical bond in three compounds is a combination of covalent, ionic, and metallic nature. The main factors governing the electronic properties are the hybrid states Mn–3d, Si–3p, and C–2p, and the bond (p–d) stabilizes the structure. The elastic constants are calculated and the conditions of the criterion of mechanical stability are checked. In addition, we have calculated the bulk, and shear modulus, Young's modulus, Poisson's ratio, and anisotropy index. The quasi-harmonic Debye model was used to study the temperature-dependent thermodynamic properties of the Mnn+1SiCn (n = 1, 2, 3) compounds. [ABSTRACT FROM AUTHOR]

In this work, we studied the magnetic stability, structural, electronic, elastic, and thermodynamic properties of the Fen+1CdCn (n = 1–3) for a new MAX phase class. To realize this study, we used the linearly augmented plane wave method (FP-LAPW) based on density functional theory implanted in Wien2k code. The exchange–correlation potential is treated with the local density approximation LSDA. The formation energies were calculated for the three compounds and showed that these compounds are thermodynamically stable in a ferromagnetic spin configuration. Further analysis was done to check the mechanical and dynamical stability based on Born criteria and phonon spectra. The result shows that the increase in the stacked layer increases the rigid layer mode and the metallicity of the compounds. To understand such behavior, both analysis based on electron density and topological analysis of electron density was done. Additionally, we show that the total magnetic moment increases while the number of layers increases. The study also used the quasi-harmonic method to predict some relevant thermal properties of the three stable compounds. [ABSTRACT FROM AUTHOR]

In order to unveil the effect of interstitial V‐doped SrO compound an ab initio calculation is carried out within the FP‐LAPW+lo method. To do this task, the modified GGA‐PBEsol potential is employed to predict structural, electronic, and magnetic properties of two alloys, SrV0.125O and SrV0.25O. The lattice parameters are found in good agreement with the existing theoretical and experimental data. The calculation shows both SrV0.125O and SrV0.25O alloys are energetically and mechanically stable. The interstitial doping changes the ionic nature of the SrO compound in half‐metallic ferromagnetic comportment one, with a spin polarization of 100% at the Fermi level. Magnetic properties are also predicted. After a deep analysis, the low magnetic moment is attributed to the strong hybridization of O‐p‐V‐d orbitals. [ABSTRACT FROM AUTHOR]

In this study, we have investigated the magnetic stability; ferromagnetic ordering; and structural, elastic, and electronic properties of Fe2PbC compound. The calculations are performed by the use of full-potential linearized augmented plane wave method implemented in WIEN2k code. We have found that the ferromagnetic state of Fe2PbC is more stable than non-magnetic state configuration at their equilibrium lattice parameters. The structural and elastic properties suggest that Fe2PbC is an anisotropic material, which is stable in the hexagonal MAX phase. The electronic structures show that Fe2PbC has metallic-covalent-ionic character. The ferromagnetic performance of Fe2PbC is confirmed by the total magnetic moment of 4.15 μB, where its main contribution is originated from Fe atoms. [ABSTRACT FROM AUTHOR]