Structural, elastic, thermodynamic, electronic, and optical properties of

The present paper aims to investigate the structural, elastic, thermodynamic, electronic, and optical properties of $$\hbox {CaMg}_{2}\hbox {AN}_{3}$$($$\hbox {A}= \hbox {Al}$$ and Ga) using first-principle calculations and quasi-harmonic Debye model. The obtained ground-state lattice parameters were in good agreement with the experimental values. Pressure effect on the structural parameters was tested up to 20 GPa, the results reveal that the contractions are higher along the c-axis than along the a-axis. The computed single-crystal elastic moduli show that the unidirectional constant $$\hbox {C}_{11}$$ is about 60% greater than $$\hbox {C}_{33}$$. Cauchy pressure and Poisson ratio suggest that the chemical bonding in $$\hbox {CaMg}_{2}\hbox {AN}_{3}$$ is a mixture of covalent and ionic characters. Elastic anisotropy was discussed using different approaches, and the results show a weak elastic anisotropy. By means of Gibbs program, we have evaluated the thermodynamic properties such as Debye temperature \uptheta _{{D}}, heat capacities $${C}_{{v}}$$ and $${C}_{{p}}$$, and expansion thermal coefficient under pressure ranging from 0 to 20 GPa and at temperature ranging from 0 to 1500 K for both compounds. The evaluated value of Dulong–Petit limit of both the semiconductors is $$360.5\ \hbox {Jmol}^{-1}\hbox {K}^{-1}$$. Band structure curves show a direct band gap of about 1.88 and 0.78 eV for $$\hbox {CaMg}_{2}\hbox {AlN}_{3}$$ and $$\hbox {CaMg}_{2} \hbox {GaN}_{3}$$, respectively. Density of states and charge densities analysis confirm the predicted ionic-covalent bonding in both nitrides. Additionally, optical functions such as the refractive index, the reflectivity, and the absorption coefficient were calculated and discussed for two polarized radiations

Pressure effect on the structural and elastic properties of ternary compounds M

Using ab initio calculations, we have performed a study of the hydrostatic pressure effect on the equilibrium volume, lattice parameters, elastic modulus, and elastic anisotropy of selected M2AlC phases with M = Ti, V, Nb, and Ta. The deviations of our calculated volume change are lower than 3% comparing with experimental measurement, lead to a discrepancy in the bulk modulus less than 15%. Our results show a linear pressure dependence of the elastic modulus and the bulk modulus. Shear elastic anisotropy factor increase with the pressure enhancement, while the compressibility anisotropy remains constant around weak values

Structural, thermal, elastic, and magnetoelectronic properties of FeNiMnZ (Z = Al, Si) quaternary Heuslers under hydrostatic pressure

In this work, we have studied the structural, thermal, elastic and magnetoelectronic properties of FeNiMnZ (Z = Al, Si) Heuslers under pressure using the pseudo-potential plane wave method. The structural optimization was performed by considering three atomic arrangements in magnetic and non-magnetic states. It was found that FeNiMnZ Heuslers are chemically stable and crystallize in the ferromagnetic YI-type structure. At zero temperature (0 K) and zero pressure (0 GPa), the obtained lattice constant (a) and bulk modulus (B) are in good accordance with the literature. The determined elastic constants (Cij), Pugh’s ratio (B/G), and universal elastic anisotropy index (AU) under pressure reveal that FeNiMnZ Heuslers are mechanically stable up to 76 GPa, behave in a ductile manner, and exhibit a notable elastic anisotropy, respectively. The band structure analysis shows that FeNiMnAl Heusler compound changes from perfect half-metallic to a metallic nature at 50.2 GPa, while FeNiMnSi Heusler compound keeps its metallicity throughout the considered pressure range. The spin polarization and total magnetic moment of FeNiMnAl (FeNiMnSi) material decrease under pressure varying from 50.2 to 88 GPa (from 0 to 80 GPa). Below 50.2 GPa, FeNiMnAl material exhibits 100% spin polarization and a total magnetic moment of 4μB, which makes it hopeful in spintronic applications

Structural, elastic, electronic and magnetic properties of Fe

We report first principle calculations on the structural, electronic and magnetic properties of antiperovskite Fe3AC; A = Al, Ga and In. Calculations show that these compounds are more stable in the magnetic states, the estimated equilibrium lattice parameters (a and V) are in agreement with the experimental data. From the single crystal elastic constants, the polycrystalline elastic moduli is estimated. Similar to previous studies on carbides antiperovskite, these compounds are good electrical conductors. The analysis of the total and partial densities of states shows that the conductivity is assured by d electrons of the transition metal atoms. The magnetic character in these compounds is mainly related to the spin polarization of Fe-d electrons. The magnetic moment per unit formula is found to decrease from 3.52 μB to 3.06 μB corresponding to Fe3InC and Fe3AlC respectively

Ab initio study of structural, electronic, and elastic properties of M 2SbP (M = Ti, Zr, and Hf)

77.84.Bw Elements, oxides, nitrides, borides, carbides, chalcogenides, etc., 71.15.Mb Density functional theory, local density approximation, gradient and other corrections, 74.62.Fj Pressure effects,

Structural, elastic, electronic and magnetic properties of Fe3AC; A = Al, Ga and In

We report first principle calculations on the structural, electronic and magnetic properties of antiperovskite Fe3AC; A = Al, Ga and In. Calculations show that these compounds are more stable in the magnetic states, the estimated equilibrium lattice parameters (a and V) are in agreement with the experimental data. From the single crystal elastic constants, the polycrystalline elastic moduli is estimated. Similar to previous studies on carbides antiperovskite, these compounds are good electrical conductors. The analysis of the total and partial densities of states shows that the conductivity is assured by d electrons of the transition metal atoms. The magnetic character in these compounds is mainly related to the spin polarization of Fe-d electrons. The magnetic moment per unit formula is found to decrease from 3.52 μB to 3.06 μB corresponding to Fe3InC and Fe3AlC respectively

Abstracts of 1st International Conference on Computational & Applied Physics

This book contains the abstracts of the papers presented at the International Conference on Computational & Applied Physics (ICCAP’2021) Organized by the Surfaces, Interfaces and Thin Films Laboratory (LASICOM), Department of Physics, Faculty of Science, University Saad Dahleb Blida 1, Algeria, held on 26–28 September 2021. The Conference had a variety of Plenary Lectures, Oral sessions, and E-Poster Presentations. Conference Title: 1st International Conference on Computational & Applied PhysicsConference Acronym: ICCAP’2021Conference Date: 26–28 September 2021Conference Location: Online (Virtual Conference)Conference Organizer: Surfaces, Interfaces, and Thin Films Laboratory (LASICOM), Department of Physics, Faculty of Science, University Saad Dahleb Blida 1, Algeria