Interaction between dislocation and vacancies in magnesium oxide: Insights from atomistic simulations and elasticity theory

We determine the interaction between an 1/2 < 110 >{(1) over bar 10} edge dislocation and charged vacancies in MgO, using both molecular static simulations and the elasticity theory developed in the framework of the elastic dipole approach. In this study, the confrontation of these two methods highlights the specific role of the dislocation core structure on the interaction. We thus show that in MgO, the edge dislocation core, within a region across the glide planes that expands over several Burgers vector, is strongly attractive for vacancies, especially those of oxygen. However, the resulting pinning force on the dislocation remains weak and should not contribute to a significant hardening.

Automated summary

In this study, the interaction between an 1/2 < 110 >{(1) over bar 10} edge dislocation and charged vacancies in MgO was determined using molecular static simulations and elasticity theory. The research highlighted the specific role of the dislocation core structure on the interaction. It was found that the edge dislocation core in MgO has a strong attractive force on vacancies, particularly oxygen vacancies.