Evaluation of theoretical, semi-empirical, and empirical approaches for determining K-shell absorption parameters for elements with Z = 18–100

This study presents a comprehensive evaluation of K-shell absorption parameters for elements with atomic numbers ranging from 18 to 100. The focus is on key parameters such as the absorption jump ratio, the absorption jump factor, the Davisson–Kirchner ratio, and the oscillator strength. The accuracy and reliability of these parameters are critically assessed using analytical, experimental, and theoretical approaches. Experimental values are compiled based on a thorough review of current literature, while theoretical values are calculated using established computational models such as XCOM and FFAST. Analytical estimations are derived through a combination of empirical and semi-empirical methods, aiming to explain systematic trends and correlations between absorption properties and atomic numbers. The findings provide valuable insights into K-shell absorption mechanisms and underscore the importance of accurate parameterization in advancing the understanding of X-ray absorption physics.