First-principles investigation of structural and electronic properties of MgCu2 Laves phase under pressure

The effects of pressure on the structural, electronic properties and ionic configuration of MgCu2 Laves phase were investigated by means of the first-principles method based on the density functional theory with generalized gradient approximation. The results for the equilibrium lattice constants are in good agreement with the previous experimental and other theoretical results. The elastic properties including the isotropic bulk modulus B, shear modulus G, Young modulus E and Poisson's ratio ν of the cubic C15-type structure MgCu2 were determined by using the Voigt–Reuss–Hill averaging scheme. The results show that the MgCu2 Laves phase is ductile according to the analysis of G/B and Cauchy pressure. The Debye temperatures obtained from the elastic stiffness constants increase with increasing pressure. Finally, the pressure-dependent behavior of density of states and ionic configuration are successfully calculated and discussed.

► The structural and electronic properties of MgCu2 Laves phase were studied. ► MgCu2 exhibits ductile feature according to the G/B and Cauchy pressure. ► The effects of pressure on elastic modulus and Debye temperatures were studied. ► The effects of pressure on DOS and ionic configuration of MgCu2 were discussed.