The improved Peierls–Nabarro equation was used to study dislocation properties on the basal plane in Mg. The generalized-stacking-fault (GSF) energy surface entering the equation was calculated by using first-principles density functional theory. The core structures including the core widths both of the edge and screw components and dissociation behavior for edge dislocations were investigated. The distance of two partials in the calculation agreed well with the values obtained from the direct ab initio simulation. Various GSF energies from the previous ab initio calculations have also been used to determine the core properties. It was demonstrated that the dissociated distance was not only determined by stable stacking-fault energy but also sensitive to the unstable stacking-fault (USF) energy and the larger the USF energy the smaller the dislocation distance. In addition because of the strong overlap of two partials the structure of dislocations in Mg cannot be dealt with using the one-dimensional model.

First-Principles Determination of Dislocation Properties in Magnesium Based on the Improved Peierls–Nabarro Equation. R.Wang, S.F.Wang, X.Z.Wu, Q.Y.Wei: Physica Scripta, 2010, 81[6], 065601