STUDY OF THE INHOMOGENEOUS ABSORPTION OF X-RAY RADIATION BY A SPHERICAL CRYSTAL SAMPLE

Abstract

When studying the absorption of X-rays, that the linear absorption coefficient is usually assumed constant throughout the entire volume of the sample under study. However, it can vary in different parts of the crystal, e.g., due to defects present or inhomogeneous inclusion of impurity and doping elements. The results of studying the features of X-ray absorption by a spherical crystalline sample under an assumption that the absorption coefficient is described by a certain function of coordinates are presented. Methods for correcting the diffraction data for such crystals, as well as numerical calculations of the absorption corrections for reflection intensities are proposed. It is shown that the inhomogeneity of absorption in a spherical sample can have a significant effect on the intensity of reflections recorded during a diffraction experiment in the framework of X-ray diffraction analysis (XKD). It is revealed that the attenuation coefficient of a diffracted beam depends on the direction of the absorption coefficient gradient. The results obtained can be used in precision X-ray diffraction analysis of the crystals of some solid solutions. The results of modeling the absorption of X-ray radiation by the samples with different laws of change in the absorption coefficient can be used to identify samples with an inhomogeneous composition.