ReaxFF reactive force field for molecular dynamics simulations of liquid Cu and Zr metals

• Published in: The Journal of chemical physics 2019-09, Vol.151 (9), p.094503-094503
• Main Authors: Huang, H. S., Ai, L. Q., van Duin, A. C. T., Chen, M., Lü, Y. J.
• Format: Article
• Language: English
• Subjects: Bulk density; Copper; Crystal structure; Embedded atom method; Equations of state; First principles; High temperature; Molecular dynamics; Thermophysical models; Thermophysical properties; Zirconium
• ISSN: 0021-9606; 1089-7690
• DOI: 10.1063/1.5112794

We develop a ReaxFF reactive force field used for the molecular dynamics simulations of thermophysical properties of liquid Cu and Zr metals. The ReaxFF parameters are optimized by fitting to the first-principles density-functional calculations on the equations of state for bulk crystal structures and surface energies. To validate the force field, we compare the ReaxFF results with those from experiments and embedded-atom-method (EAM) potentials. We demonstrate that the present ReaxFF force field well represents structural characteristics and diffusion behaviors of elemental Cu and Zr up to high-temperature liquid regions. It reasonably reproduces the thermodynamic processes associated with crystal-liquid interface. In particular, the equilibrium melting temperatures show better agreement with experimental measurements than the results from EAM potentials. The ReaxFF reactive force field method exhibits a good transferability to the nonreactive processes of liquid systems.