The first principles investigation of lattice dynamical and thermodynamical properties of Al2Ca and Al2Mg compounds in the cubic Laves structure

In the framework of density functional theory, the structural, lattice dynamical and thermodynamical properties of the C15-type of Al2Ca and Al2Mg compounds are investigated. The calculated lattice constants are in good agreement with the other works. The results show that these compounds are dynamically stable in the considered structure. The temperature dependence of the various thermodynamical quantities such as internal energy, free energy, entropy, and heat capacity are also predicted within the harmonic approximation, and the observed trends are discussed in detail.

► We have studied the lattice dynamical and thermodynamical properties of the Al2Ca and Al2Mg. ► The present results show that the both compounds are dynamically stable. ► Free energy calculation demonstrates that Al2Mg is thermodynamically more stable than Al2Ca.