Melting curve of face-centered-cubic nickel from first-principles calculations

摘要

The melting curve of Ni up to 100 GPa has been calculated using first-principles methods based on density functional theory (DFT). We used two complementary approaches: (i) coexistence simulations with a reference system and then free-energy corrections between DFT and the reference system, and (ii) direct DFT coexistence using simulation cells including 1000 atoms. The calculated zero pressure melting temperature is slightly underestimated at 1637 ± 10 K (experimental value is 1728 K), and at high pressure is significantly higher than recent measurements in diamond-anvil cell experiments [Phys. Rev. B 87, 054108 (2013)]. The zero pressure DFT melting slope is calculated to be 30 ± 2 K, in good agreement with the experimental value of 28 K.