Development of suitable interatomic potentials for simulation of liquid and amorphous Cu-Zr alloys

This work was supported by the United States Department of Energy, Office of Basic Energy Sciences as follows: efforts at the Ames Laboratory were supported under Contract No. DE-AC02-07CH11358 and use of the Advanced Photon Source was supported under Contract No. DE-AC02-06CH11357.We present a new semi-empirical potential suitable for molecular dynamics simulations of liquid and amorphous Cu-Zr alloys. To provide input data for developing the potential, new experimental measurements of the structure factors for amorphous Cu64.5Zr35.5 alloy were performed. In this work, we propose a new method to include diffraction data in the potential development procedure, which also includes fitting to first-principles and liquid density and enthalpy of mixing data. To refine the new potential, we used first-principles and liquid enthalpy of mixing data published earlier combined with the densities of liquid Cu64.5Zr35.5 measured over a range of temperatures. We show that the potential predicts a liquid-to-glass transition temperature that agrees reasonably well with experimental data. Finally, we compare the new potential with two previously developed semi-empirical potentials for Cu-Zr alloys and examine their comparative and contrasting descriptions of structure and properties for Cu64.5Zr35.5 liquids and glasses