Texture corrections for total scattering functions

• Published in: Acta crystallographica. Section A, Foundations and advances Vol. 76; no. 3; pp. 302 - 317
• Main Authors: Cervellino, Antonio, Frison, Ruggero
• Format: Journal Article
• Language: English
• Published: 5 Abbey Square, Chester, Cheshire CH1 2HU, England International Union of Crystallography 01.05.2020
• Subjects: Debye scattering equation; pair distribution function; Research Papers; texture; texture; pair distribution function; Debye scattering equation
• ISSN: 2053-2733; 2053-2733
• DOI: 10.1107/S2053273320002521

Many functional materials are today synthesized in the form of nanoparticles displaying preferred orientation effects to some small or large extent. The analysis of diffraction data of such kinds of systems is best performed in the framework of the total scattering approach that prescinds from translation symmetry assumptions. Therefore modified expressions were derived for the most common total scattering functions, in particular the Debye scattering equation (DSE) which yields the texture‐averaged differential cross section as a function of atomic coordinates and texture parameters. The modified DSE encodes higher‐order even spherical Bessel functions which account for the texture effect. Selection rules arising from experimental geometries and symmetries are discussed. In addition the duality of the texture effect is introduced showing the effects of texture on both the I(Q) and . The paper includes several definitions and appendices which are meant to be useful for those involved in the development of crystallographic computing. The Debye scattering equation (DSE) is generalized and augmented in order to account for moderate texture effects, yielding the differential cross section as a function of atomic coordinates and texture coefficients subject to symmetry constraints. Implications for the evaluation of the pair distribution function (PDF) as a direct transform of powder diffraction data from textured samples are also discussed.