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research papers
Some mathematical and optical-analogue results are used to describe the effect of introducing a non-linear term into the regression equation defining a previously described model of crystal-growth disorder. With this extended model it has been found that lattices may be produced which have completely different distributions of the two scattering species but which nevertheless give rise to indistinguishable diffraction patterns. In addition it has been found that in certain cases the disorder diffuse scattering has two maxima within the reciprocal unit cell even though only nearest-neighbour interactions are involved.