Atomistic dislocation simulation of aluminum using a tight-binding method

Atomistic simulation of dislocation in aluminum has been performed using a tight-binding method where the parameters are based on the works of Mehl and Papaconstantapoulous at the Naval Research Laboratory. We study the dissociation of a perfect edge dislocation (the dislocation line is along the $[11{\overline 2}]$ direction) of Burgers vector of $\frac{a}{2}[1{\overline 1} 0]$ into two partials of $\frac{a}{6}[2 {\overline 1}{\overline 1}] $ and $\frac{a}{6}[1 {\overline 2}1] $ on the $(111)$ slip plane. By performing a large scale atomistic relaxation, we observe a separation of partials of about 14~\AA\ and a stacking fault region. We will comment on the estimate of partials separation predicted by the elasticity theory, which relates to certain quantities such as the stacking fault energy.