First-principles calculations of the Zn–Zr system

First-principles calculations of the free energy of the intermetallic phases of the Zn–Zr system have been performed. The likely structures of the two allotropes of Zn3Zr are proposed and the structure of Zn2Zr3 is determined. The 0 K phase diagram for this system is calculated using the convex hull construction. Two compounds, ZnZr2 and Zn2Zr3, that previously were not considered to form part of the equilibrium phase diagram have been shown to become stable at high temperatures thanks to calculations of their vibrational free energy via the supercell approach within the harmonic approximation. The results from this work will later be used to develop a fully consistent thermodynamic model for this binary.