AbstractA systematic defect characterization by X‐ray diffraction was carried out on crystalline KCl system with Cd++impurities at various levels, viz. 2, 4, 6, 8, and 10 mole%. Quantitative estimation of the amount and nature of defects was done from the integrated X‐ray intensity measurements of the samples. Further analyses of the experimental data indicate enhancement of the Debye‐Waller factor with concentration of Cd++impurities. The measured density and the cell constant values at room temperature yield vacancy estimations for the system. The observed change of Bravais lattice of the system for Cd++concentrations from 4 mole% with appreciable enhancement of intensity of Bragg reflections of mixed indices are reported and disc