On the use of laboratory X-ray diffraction equipment for Pair Distribution Function (PDF) studies

Abstract

At present synchrotron and neutron sources are the preferred choice for PDF analysis, but there is clearly an increasing need for a PDF solution based on inhouse diffraction equipment. Such a solution, though limited, will benefit areas where quick feedback about the materials properties is important and will allow the routine application of PDF analysis for materials characterization in university laboratories as well as industrial R&D departments. One interesting application is the use of the PDF technique for comparing amorphous pharmaceutical substances [1]. It is worth mentioning that the use of in-house diffraction equipment for PDF analysis has been reported on numerous occasions (see for example [2–4]).

This article describes the latest developments of laboratory X-ray equipment for PDF analysis and discusses some results obtained with such equipment. Three examples — C₆₀, amorphous MoS3 and crystalline CeO₂ — were chosen to demonstrate different aspects of PDF data collection optimization.