Stability, elastic properties and electronic structures of L12-ZrAl3 and D022-ZrAl3 up to 40 GPa Original Research Article

The effects of high pressures on structure stability, elastic properties and electronic structures of zirconium trialuminide L12- and D022-ZrAl3 compounds have been investigated by first-principles calculations within the local density approximation. The equilibrium structure and formation energy show that L12-ZrAl3 is more stable than D022-ZrAl3 at the applied pressure. The elastic properties and Debye temperatures of (L12, D022)-ZrAl3 increase with the increasing pressure and the calculated values in the ground state are in good agreement with the available experiment data. The mechanical anisotropic properties were discussed using the universal anisotropic index AU. The sound velocities along the [100], [110] and [111] directions were also calculated for both phases. The calculated electronic properties under high pressures suggest that the decreased electronic density of states (DOS) at the Fermi level and the changed charges distribution lead to the observed decrease of the structural stability for (L12, D022)-ZrAl3 under high pressures.