Warning! Note that 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 optimized separately. As with all interatomic potentials, please check to make sure that the performance is adequate for your problem.
Citation: A. Hashibon, A.Y. Lozovoi, Y. Mishin, C. Elsässer, and P. Gumbsch (2008), "Interatomic potential for the Cu-Ta system and its application to surface wetting and dewetting", Physical Review B, 77(9), 094131. DOI: 10.1103/physrevb.77.094131.
Abstract: An angle-dependent interatomic potential has been developed for the Cu-Ta system by crossing two existing potentials for pure Cu and Ta. The cross-interaction functions have been fitted to first-principles data generated in this work. The potential has been extensively tested against first-principles energies not included in the fitting database and applied to molecular dynamics simulations of wetting and dewetting of Cu on Ta. We find that a Cu film placed on a Ta (110) surface dewets from it, forming a Cu droplet on top of a stable Cu monolayer. We also observe that a drop of liquid Cu placed on a clean Ta (110) surface spreads over it as a stable monolayer, while the extra Cu atoms remain in the drop. The stability of a Cu monolayer and instability of thicker Cu films are consistent with recent experiments and first-principles calculations. This agreement demonstrates the utility of the potential for atomistic simulations of Cu-Ta interfaces.
Notes: Prof. Mishin requested the following be noted: There was a typing error in the original ADP paper (Y. Mishin, et al., Acta Mat. 53, 4029 (2005)). More information and a correction can be found in the FAQ. Update 17 Jan. 2014: Prof. Mishin noted that "Our ADP Ta potential has a known error: the elastic constants predicted by the potential as a factor of two different from those reported in the paper. This was the result of a bug in the fitting code that was used during the potential development. All other properties are exactly as reported in the paper. The mixed Cu-Ta interactions are also fine. However, because of this error in the elastic constants, the potential cannot be recommended for studying mechanical properties of pure Ta." Update: The 2015--Purja-Pun-G-P--Cu-Ta ADP potential has supplanted this potential.