Effect of heavy atom disorder on the intensities of powder xrd lines of YBa2Cu3O7-y

Abstract

It is shown that heavy atom disorder resulting from Y↔ Ba, Ba ↔ Cu and Y↔Cu interchanges due to local stoichiometric constraints can cause significant changes in the intensities of X-ray powder diffraction lines of YBa 2 Cu 37 O 7-y. A comparison of the theoretically predicted intensities with published patterns for specimens prepared by the conventional dry route reveals that Ba↔Cu interchanges involving copper atoms in the CuO 2 planes can occur quite frequently and may be mistaken for (00l) texture. © 1990, Taylor & Francis Group, LLC. All rights reserved.