Developing a second nearest-neighbor modified embedded atom method interatomic potential for lithium

Abstract

This paper reports the development of a second nearest-neighbor modified embedded atom method (2NN MEAM) interatomic potential for lithium (Li). The 2NN MEAM potential contains 14 adjustable parameters. For a given set of these parameters, a number of physical properties of Li were predicted by molecular dynamics (MD) simulations. By fitting these MD predictions to their corresponding values from either experimental measurements or ab initio simulations, these adjustable parameters in the potential were optimized to yield an accurate and robust interatomic potential. The parameter optimization was carried out using the particle swarm optimization technique. Finally, the newly developed potential was validated by calculating a wide range of material properties of Li, such as thermal expansion, melting temperature, radial distribution function of liquid Li and the structural stability at finite temperature by simulating the disordered–ordered transition.