Diffraction analysis of perovskite-like oxides containing irregular intergrowths

Features of the X-ray intensity distributions caused by the presence of random and nonrandom stacking faults (irregular intergrowths) in layered perovskite-like oxides are studied by a computer simulation technique. It is shown that, apart from the stacking fault properties, the position, profile and intensity of a diffraction peak are dependent on the ratio between the c lattice parameter of the crystal and the thickness of the new structural fragment formed as a result of the stacking fault. A means of characterizing the stacking faults on the basis of the relative positions of pairs of diffraction peaks is presented. The approach is exemplified by the X-ray diffraction study of a disordered single crystal of the system Bi–Sr–Ca–Cu–O.