Influence of vacancies on melting points of tungsten at high pressure.

[Display omitted] • Systematically compared with four potentials, it is found that the GAP model can well describe the equilibrium mechanical properties, compressional properties, and the thermal expansion property. • At 400 GPa, the melting point does not change regularly with the vacancy concentration, and the vacancy can slightly reduce the melting point. • In the range of 0–400 GPa, the calculated melting curves for both the perfect crystal and the system with a vacancy concentration of 0.03 are significantly higher than the LH-DAC results and close to the shock melting point. Melting points of tungsten with different vacancy concentrations are researched under pressure via molecular dynamics simulations. By testing the ability of four potential models to describe the equilibrium mechanical properties, compressional properties, and thermal expansion properties, the Gaussian approximation potential model is selected for studying melting points at high pressure. The vacancy can slightly reduce the melting point, and at 400 GPa the melting point decreases the most at a vacancy concentration of 0.03, reaching 500 K. The melting curve with the vacancy concentration of 0.03 still exhibits a high slope, approaching the shock melting point. [ABSTRACT FROM AUTHOR]