Study of structural, electronic, elastic, magnetic and thermal properties of the new half-metallic Heusler alloys Cr2LuSn1−xPbx: by DFT approach

The structural, electronic, mechanical and magnetic properties were investigated for Cr2LuSn1−xPbx quaternary Heusler compounds by employing first-principles calculations framed fundamentally within density functional theory. The exchange–correlation potential is evaluated using the generalized gradient approximation (GGA)within the Perdew–Burke–Ernzerhof parameterization. We optimized our structure, and the most stable crystal structure is AlCu2Mnl-type, and at equilibrium, equilibrium lattice parameters have been determined. The calculated lattice constants for Cr2LuSn and Cr2LuPb are 6.5906 Å and 6.6769 Å, respectively. The electronic structures show that both compounds have half-metallic properties by showing 100% spin polarization near the Fermi level. The electronic band structures and density of states of our compounds show a half metallic character with total magnetic moments, 5.00 μb\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\mu }_{\mathrm{b}}$$\end{document} per formula unit with indirect band gap, 0.527 eV and 0.300 eV for Cr2LuSn and Cr2LuPb, respectively. The mechanical stability reveals that all our compounds are stable mechanically. The Young's modulus, Poisson's ratio, anisotropy factor Zener and density were calculated and discussed in detail. Furthermore, the temperature and pressure effect on bulk modulus, Debye temperature and heat capacity at constant volume and constant pressure Cv,\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${C}_{\mathrm{v},}$$\end{document}, respectively, have been investigated by the quasi-harmonic Debye model. These alloys seem to be a potential candidate of spintronic devices.