title: Powder diffraction in Bragg-Brentano geometry with straight linear detectors.
abstract: A common way of speeding up powder diffraction measurements is the use of one- or two-dimensional detectors. This usually goes hand in hand with worse resolution and asymmetric peak profiles. In this work the influence of a straight linear detector on the resolution function in the Bragg-Brentano focusing geometry is discussed. Because of the straight nature of most modern detectors geometrical defocusing occurs, which heavily influences the line shape of diffraction lines at low angles. An easy approach to limit the resolution-degrading effects is presented. The presented algorithm selects an adaptive range of channels of the linear detector at low angles, resulting in increased resolution. At higher angles the whole linear detector is used and the data collection remains fast. Using this algorithm a well behaved resolution function is obtained in the full angular range, whereas using the full linear detector the resolution function varies within one pattern, which hinders line-shape and Rietveld analysis.
authors.affiliation: Department of Condensed Matter Physics, Charles University in Prague, Ke Karlovu 5, 121 16 Prague 2, Czech Republic.
authors.forename: Dominik
authors.initials: D
authors.lastname: Kriegner
authors.affiliation: Department of Condensed Matter Physics, Charles University in Prague, Ke Karlovu 5, 121 16 Prague 2, Czech Republic ; Max IV Laboratory, Lund University, Ole Römers väg 1, 223 63 Lund, Sweden.
authors.forename: Zdeněk
authors.initials: Z
authors.lastname: Matěj
authors.affiliation: Department of Condensed Matter Physics, Charles University in Prague, Ke Karlovu 5, 121 16 Prague 2, Czech Republic.
authors.forename: Radomír
authors.initials: R
authors.lastname: Kužel
authors.affiliation: Department of Condensed Matter Physics, Charles University in Prague, Ke Karlovu 5, 121 16 Prague 2, Czech Republic.
authors.forename: Václav
authors.initials: V
authors.lastname: Holý
keywords: Bragg–Brentano; line shape; linear detector; powder diffraction; resolution function
references.citation: Acta Crystallogr A. 2002 Mar;58(Pt 2):190-200
references.pmid: 11832590
references.citation: J Appl Crystallogr. 2013 Aug 1;46(Pt 4):1162-1170
references.pmid: 24046508