A first-principles investigation of the importance of various calculation parameters on self-diffusion coefficient calculations in FCC metals

Using first-principles calculations based on density functional theory to determine self-diffusion coefficients in metals has been an invaluable tool to the materials community, as diffusion is the primary mechanism of mass transfer in metals. As the materials community moves towards high-throughput or automated techniques for calculating properties of large materials data sets, understanding which parameters (vibrational method, supercell size, etc) have the most significant effect on diffusion properties is critical. In this work, diffusion parameters and thermodynamic properties of Ag, Cu, and Ni were found using first-principles calculations and the following variables: 32, 64, and 108 atom supercells, both the LDA and PBEsol exchange and correlation functionals, and two vibrational entropy calculation methods. Comparisons of the accuracy, computational expense, and necessity of each calculation parameter will be discussed in light of its effects on diffusion coefficients, vacancy concentration, and other thermodynamic properties.