An explicit expression for the elastic potential energy stored within a thin foil, by a dissociated dislocation running parallel to the free surfaces, was obtained under conditions of isotropic elasticity. It was found that the energy depended, in particular, upon the positions of the 2 partials in the foil and upon the thickness. For such ultra-thin foils, which facilitated the observation of partial dislocation cores with near-atomic resolution, the theory predicted rapid changes in the separation distance, with thickness. This result was in agreement with previous experimental observations of separation distance, obtained by using the so-called forbidden-reflection lattice imaging technique.

The Elastic Potential Energy of a Thin Foil Deformed by an In-Plane 60° Dislocation. S.Youssef, R.Bonnet: Philosophical Magazine, 2007, 87[31], 4935-48