Analytical contrast factor of dislocations along orthogonal diad axes

An analytical expression valid for any crystal system is proposed for the diffraction contrast factor of dislocations lying along a diad axis with another diad perpendicular to it. This symmetry requirement is common to several slip systems in real materials, for which the proposed solution can provide a direct relationship between diffraction line broadening, dislocation slip system and elastic properties. As an example of the utility of the contrast factor in analytical form, the main slip system of Fluorite-type structures <1-10>{111} is considered and the dependence of the line broadening anisotropy is shown as a function of the elastic anisotropy and Poisson's ratio.