Multiple-beam x-ray diffraction near exact backscattering in silicon

We examined multiple-beam effects accompanying a backscattering Bragg reflection from a silicon crystal. Silicon crystals are frequently used in x-ray diffraction applications due to their high degree of perfection. Backscattering Bragg reflections have been employed for x-ray monochromatization, energy analysis, and other tasks. Multiple-beam effects have been found to be unavoidable for backscattering of hard x-rays from silicon, but little experimental data had previously been collected on these effects. Detailed rocking curves of the (12 4 0) Bragg reflection near backscattering are included and compared to the predictions of the dynamical diffraction theory. Intensity data of the accompanying reflected beams are also provided.