A Computer Simulation for a Dislocation in Rare Gas Solids

A computer simulation for a screw dislocation was performed in rare gas solids, especially in an argon crystal. The 12–6 type Lennard-Jones potential was used for the interactions between atoms. The dislocation in the crystal always split into Schockley partials. The atomistic structure and the motion of the dislocations were strongly sensitive to the surface boundary condition of the model crystal, and the Peierls force was very small compared with the boundary force. To eliminate the boundary effect, an artificial boundary condition was adopted, and the Peierls stress was estimated as τ_P = (5 ~ 10) × 10⁻⁵μ (shear modulus).