Molecular dynamics simulations for liquid Molybdenum: Structural and atomic transport properties

Molecular dynamic (MD) simulation is performed using a second neighbor Finnis-Sinclair (FS) potential to study structural and atomic mass transport properties of molybdenum in the liquid phase for a temperature (T) range of 3100 to 3800 K. The Computed results for the pair correlation function, structure factor, and coordination number are discussed with similar findings. Transport coefficients like viscosity and self-diffusion coefficient follow Arrhenius law, which estimates activation energy between 1.34 to 1.62 eV. The discrepancy in computed densities and other properties beyond 3800 K is discussed, given the nature of interaction potentials and binding in liquid molybdenum. It is shown that EAM, MEAM, and FS potentials show analogous repulsive character and therefore give comparable results for structural properties. However, the attractive part of the interaction potential, which determines the binding in molybdenum is responsible for the difference in various high-T physical properties reported in the study. The sensitivity of physical properties on the attractive part of the interaction potential thus demands to incorporate the effect of temperature dependency of electron density-of-state (e-dos) and angular forces into the interaction for a proper account of the binding in liquid molybdenum. Key Words: Finnis-Sinclair potential, molecular dynamics simulation, molybdenum, structural and atomic transport properties. (author)