Illustrated formalisms for total scattering data: a guide for new practitioners. Issue 1 (22nd January 2021)

• Record Type: Journal Article
• Authors: Peterson, Peter F.; Olds, Daniel; McDonnell, Marshall T.; Page, Katharine
• Is Part Of: Journal of applied crystallography. Volume 54:Issue 1(2021)
• Page Start: 317
• Page End: 332
• Publication Date: 2021-01-22
• Subjects: total scattering -- pair distribution function; Crystallography -- Periodicals; 548.05
• DOI: 10.1107/S1600576720015630
• Languages: English
• ISSNs: 0021-8898

Abstract

Abstract : This article provides a detailed and visual presentation of the derivations of and relationships between many of the commonly employed functional forms of real‐ and reciprocal‐space data employed by the worldwide total scattering community. Abstract : The total scattering method is the simultaneous study of both the real‐ and reciprocal‐space representations of diffraction data. While conventional Bragg‐scattering analysis (employing methods such as Rietveld refinement) provides insight into the average structure of the material, pair distribution function (PDF) analysis allows for a more focused study of the local atomic arrangement of a material. Generically speaking, a PDF is generated by Fourier transforming the total measured reciprocal‐space diffraction data (Bragg and diffuse) into a real‐space representation. However, the details of the transformation employed and, by consequence, the resultant appearance and weighting of the real‐space representation of the system can vary between different research communities. As the worldwide total scattering community continues to grow, these subtle differences in nomenclature and data representation have led to conflicting and confusing descriptions of how the PDF is defined and calculated. This paper provides a consistent derivation of many of these different forms of the PDF and the transformations required to bridge between them. Some general considerations and advice for total scattering practitioners in selecting and defining the appropriate choice of PDF in their own research are presented. This contribution aims to benefit people starting in the field or trying to compare their results with those of other researchers.