A detailed analysis of divergent‐beam (DB) X‐ray reflexion from a crystal surface is given. It has been shown theoretically and experimentally that DB methods of determining the substructure misorientation described previously yield erroneous results. The paper deals with two rather simple methods of determining the angles between the same planes in neighbouring blocks in the case of reflecting planes being parallel to the crystal surface.

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We report the attempt to prepare free-standing spherically bent Si crystals with radii of curvature as small as 30 cm and large uniform working areas up to several cm2. We also report on the use of these crystals in the Laue geometry to record two-dimensional high spatial resolution x-ray images in the hard x-ray region (λ∼0.5 Å). We discuss how these bent crystals were made, and show how these spherically bent crystals were used in the Laue geometry to obtain hard x-ray images of test objects at the silver K-alpha wavelength at two different magnifications. The mean spatial resolution of this x-ray imaging scheme, determined from the recorded image traces, was found to be better than 10 μm over a field of view of 1.5×1.5 mm. Contributions of possible focusing mechanisms (dynamical and polychromatic) are discussed. Additional theoretical understanding of how such a scheme is working is needed.

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C60 molecules, in diffraction terms, is a quite novel object- covered by scattering points large sphere (D≅0.5acub). The peculiarities of the diffraction distribution and its variation near the order-disorder phase transition are defined from the buckybal's molecular form-factor, fmol. The comparison of calculated diffraction distributions and experimental data proved advantage of the C60 “jump rotation” model at middle and high temperatures.