Structural, mechanical, thermodynamic and electronic properties of Pt₃M (M = Al, Co, Hf, Sc, Y, Zr) compounds under high pressure

In this work, the impacts of pressure on the structural, mechanical, thermodynamic and electronic properties of typical Pt₃M (M = Al, Co, Hf, Sc, Y, Zr) compounds were investigated systematically by the first-principles density function theory calculations. The calculated lattice parameters, volume and elastic constants of Pt₃M compounds are in good agreement with available experimental and calculation values. With the increase in pressure, the lattice parameters and volume of Pt₃M compounds decrease, while the elastic constants, bulk modulus, shear modulus and Young’s modulus increase. The variations in Pugh’s ratio and Poisson’s ratio indicate that these Pt₃M compounds are mechanically stable and ductile. The mechanical anisotropy of these Pt₃M compounds is enhanced by rising pressure. Thermodynamic analysis indicates that sound velocity and Debye temperature increase with the increase in stress. The charge distribution does not change obviously, implying that no phase transition occurs in the range of 0–100 GPa.