Removal of the white-radiation background from data collected with, β-filtered MoKα, and AgKα X-rays

Abstract

The usual methods of collecting diffraction data using β-filtered X-rays lead to significant systematic errors in the low-angle data, especially when the shorter-wavelength radiations (e.g. Mo Kα and Ag Kα) are employed. These errors arise because of the structure introduced into the white-radiation background by the filter absorption edge. A technique is proposed for the correct removal of the structured white-radiation profile from low-angle data. Some experimental measures are recommended which will reduce the number of reflexions affected. The proposed procedures are simple and can be carried out 'by hand' or, preferably, incorporated in the data-reduction program. Given an accurate and easily applied technique for removing the white-radiation background, it is argued that in the majority of cases data collection with β-filtered radiation is to be preferred over other methods such as the use of monochromated radiation or balanced filters.