The strain field of isolated screw and edge dislocation cores in aluminium were calculated using density-functional theory and a flexible boundary condition method. Nye tensor density contours and differential displacement fields were used to accurately bound Shockley partial separation distances. The results of 5 to 7.5A (screw) and 7.0 to 9.5A (edge) eliminated uncertainties resulting from the wide range of previous results based upon Peierls-Nabarro and atomistic methods. Favorable agreement of the predicted cores with limited experimental measurements demonstrated the need for quantum mechanical treatment of dislocation cores.

Prediction of Dislocation Cores in Aluminum from Density Functional Theory. C.Woodward, D.R.Trinkle, L.G.Hector, D.L.Olmsted: Physical Review Letters, 2008, 100[4], 045507