Atomic-scale calculation of energies of Cu (001) twist boundaries

Unrelaxed energies for Cu (001) twist grain boundaries (GBs) have been calculated using Modified Analytical Embedded Atom Method (MAEAM). The results show that, except zero energy at 0° (perfect crystal), a small cusp exists at the twist angle of 36.87° corresponding to \varSigma=5, which agrees with experimental results. For other misorientations, the GB energies keep almost constant even for a twist angle as small as 1.94°. Homogeneous expansion and that perpendicular to the GB plane result in obvious decrease of energy, especially the latter.