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A methodology is presented to characterize the crystallographic texture of atomic configurations on the basis of Euler angles. Texture information characterized by orientation map, orientation distribution function, texture index, pole figure and inverse pole figure is obtained. The paper reports the construction and characterization of the texture of nanocrystalline configurations with different grain numbers, grain sizes and percentages of preferred orientation. The minimum grain number for texture‐free configurations is ∼2500. The effect of texture on deducing grain size from simulated X‐ray diffraction curves is also explored as an application case of texture analysis. In addition, molecular dynamics simulations are performed on initially texture‐free nanocrystalline Ta under shock‐wave loading, which shows a ⟨001⟩ + ⟨111⟩ double fiber texture after shock‐wave compression. [ABSTRACT FROM AUTHOR]

Diffuse X-ray scattering has been an important tool for understanding the atomic structure of binary systems for more than 50 years. The majority of studies have used laboratory-based sources providing 8 keV photons or synchrotron radiation with similar energies. Diffuse scattering is weak, with the scattering volume determined by the X-ray absorption length. In the case of 8 keV photons, this is not significantly different from the typical extinction length for Bragg scattering. If, however, one goes to energies of the order of 100 keV the scattering volume for the diffuse scattering increases up to three orders of magnitude while the extinction length increases by only one order of magnitude. This leads to a gain of two orders of magnitude in the relative intensity of the diffuse scattering compared with the Bragg peaks. This gain, combined with the possibility of recording the intensity from an entire plane in reciprocal space using a two-dimensional X-ray detector, permits time-resolved diffuse scattering studies in many systems. On the other hand, diffraction features that are usually neglected, such as multiple scattering, come into play. Four types of multiple scattering phenomena are discussed, and the manner in which they appear in high-energy diffraction experiments is considered. [ABSTRACT FROM AUTHOR]

Examines the use of asymmetric laue crystal in synchrotron X-rays. Measurement of the rocking curve; Factors controlling the angle of the lattice plane; Improvement on asymmetric laue crystal.

Part I. Presents a study which demonstrated the ability of asymmetric Laue crystals to focus X-rays sagitally. Extent of focusing; Facilitation of anti clastic bending; Sagital focusing with a single-bounced monochromator.

Examines the use of a prism to discriminate between different harmonic orders of a two-crystal non-dispersive monochromator. Effect of the refractive prism on the silicon 333 reflection; Suppression of higher-order harmonics; Ability of the second crystal to allow the selection of a specific harmonic order.