Application of a single-reflection collimating multilayer optic for X-ray diffraction experiments employing parallel-beam geometry

Abstract

Instrumental aberrations of a parallel-beam diffractometer equipped with a rotating anode X-ray source, a single-reflection collimating multilayer optic and a parallel-plate collimator in front of the detector have been investigated on the basis of standard measurements (i.e. employing stress-and texture-free isotropic powder specimens exhibiting small or negligible structural diffraction line broadening). It has been shown that a defocusing correction, which is a major instrumental aberration for diffraction patterns collected with divergent-beam (focusing) geometries, is unnecessary for this diffractometer. The performance of the diffractometer equipped with the single-reflection collimating multilayer optic (single-reflection mirror) is compared with the performance of the diffractometer equipped with a Kirkpatrick-Baez optic (cross-coupled Gö bel mirror) on the basis of experimental standard measurements and ray-tracing calculations. The results indicate that the use of the single-reflection mirror provides a significant gain in photon flux and brilliance. A high photon flux, high brilliance and minimal divergence of the incident beam make the setup based on the single-reflection mirror particularly suitable for grazing-incidence diffraction, and thus for the investigation of very thin films (yielding low diffracted intensities) and of stress and texture (requiring the acquisition of large measured data sets, corresponding to the variation of the orientation of the diffraction vector with respect to the specimen frame of reference). A comparative discussion of primary optics which can be used to realise parallel-beam geometry shows the range of possible applications of parallelbeam diffractometers and indicates the virtues and disadvantages of the different optics. research papers J. Appl. Cryst. (2008). 41, 124-133 M. Wohlschlö gel et al. Single-reflection collimating multilayer optic 125

Microstructure Characterization of Multilayer Thin Coatings ZrN/Si3N4 by X‐Ray Diffraction Using Noncoplanar Measurement Geometry

“…X‐ray diffraction experiments were performed on an Ultima IV X‐ray diffractometer (Rigaku) equipped with X‐ray tube providing Cu K α radiation ( nm). The measurements were carried out in a parallel‐beam geometry supplied with cross‐beam optics unit providing a parallel beam.…”

Interface-induced microstrain in La0.67Ca0.33MnO3/YBa2Cu3O7 superlattices

“…The Cu Ka radiation emerging from a microfocus rotating-anode X-ray source (Bruker TXS) was converted into a monochromated and quasi-parallel beam by a collimating X-ray mirror (Xenocs) [25].…”

Interdiffusion and stress development in Cu–Pd thin film diffusion couples

“…Cu-Kα radiation, emerging from the point focus of a rotating-anode X-ray source (Bruker TXS) operating at 50 kV and 20 mA, was converted into a quasi-parallel beam by a collimating X-ray mirror (Xenocs) [22,23]. The diffracted beam passed a parallel plate collimator (acceptance angle 0.23°) before being detected by a scintillation counter.…”