X-ray diffraction peaks from partially ordered misfit dislocations

We calculate the x-ray diffraction peak profiles from distributions of misfit dislocations in the whole range of their positional correlations, from completely random to periodic. Both the spatial integration and the integration over the dislocation ensemble are performed by Monte Carlo techniques. The diffraction peaks from thin relaxed films consisting of a narrow coherent and a broad diffuse component are explained. Correlation functions are calculated analytically for different types of positional correlations between dislocations.