  We developed new modified embedded-atom method (MEAM) interatomic potentials
for the Mg-Al alloy system using a first-principles method based on density
functional theory (DFT). The materials parameters, such as the cohesive energy,
equilibrium atomic volume, and bulk modulus, were used to determine the MEAM
parameters. Face-centered cubic, hexagonal close packed, and cubic rock salt
structures were used as the reference structures for Al, Mg, and MgAl,
respectively. The applicability of the new MEAM potentials to atomistic
simulations for investigating Mg-Al alloys was demonstrated by performing
simulations on Mg and Al atoms in a variety of geometries. The new MEAM
potentials were used to calculate the adsorption energies of Al and Mg atoms on
Al (111) and Mg (0001) surfaces. The formation energies and geometries of
various point defects, such as vacancies, interstitial defects and
substitutional defects, were also calculated. We found that the new MEAM
potentials give a better overall agreement with DFT calculations and
experiments when compared against the previously published MEAM potentials.
