Theoretical Analysis of the X-ray Mass Absorption Coefficient Produced by the Photoelectric Effect and Comparison of the Accuracy of a Computational Model of NiO and SiC

This study aims to analyze and calculate the mass absorption coefficient of X-rays resulting from the photoelectric effect in nickel oxide and silicon carbide compounds in the energy range of 1-100 keV by using a simple, approximate, and semi-empirical theoretical model with constants that depend on the type of interaction. The effective atomic number was then calculated, and the theoretical model was used to calculate the mass absorption coefficient of the compounds. The results extracted from the application of the theoretical model were compared with the experimental or semi-experimental results extracted from the databases of the programs XCOM and FFAST. To improve the accuracy of the theoretical model, the real atomic number was replaced by the effective atomic number, as the results showed good agreement in the low energy range of the studied model. However, the accuracy of the model decreases at energies higher than 30 keV. The results were improved when using the effective atomic number, especially in the compound where there is a difference in the atomic numbers of its components. Therefore, incorporating the concept of the effective atomic number clearly enhances the accuracy of the theoretical model, making it more realistic in describing mass absorption behaviour. This simple modification to the theoretical model showed a clear improvement in the theoretical results. All calculations and graphical representations were performed using the MATLAB 2020 program.