Mixed intermetallic potentials for Fe-Cu compounds

Metastable Fe-Cu alloys are of considerable scientific interest, and an efficient interatomic potential is crucial for reliable atomistic simulations. Interatomic potentials developed for pure Fe and pure Cu are difficult to mix for the Fe-Cu alloys since the analytic function form of pure Fe is not of the same type of pure Cu potential. Additionally, elemental potentials taken from alloy descriptions may not work well for the pure species. This is particularly true if the elements were fit for compounds instead of being optimised separately. In this article, we present compatible analytic function forms that work for pure species and are easily mixed with two adjustable parameters for their alloys. We tested the proposed potentials to make sure that the performance is adequate for pure species as well as their alloys. The predicted values were in good agreement with experimental results.