We constructed many distinct grain boundaries in a periodic cell size of 15a0/2, where a0 is the lattice spacing. Grain boundary energies (T= 0 K, the enthalpy were computed using atomistic simulations based on the embedded-atom method (EAM) potential. We currently simulated 20 Σ3 boundaries using EAM potentials fabricated by M.I. Mendelev (Ames Laboratory). These potentials have been used in the atomistic simulation by Prof. Taira Okita.
For each macroscopic grain boundary structure, large sets of initial configurations, roughly from 102 to 104, were minimized using the conjugate-gradient method in the LAMMPS code.