![]() At synchrotron sources this is possible with sub-second integration times using two-dimensional detectors (He, 2009 ▶ Liermann et al., 2010 ▶). For such detailed investigations one needs fast recording of high-quality powder diffraction data in order to enable in situ investigation. pressure cells, ovens, cryostats or chemical reaction cells. The use of X-ray photons, because of their high penetration depth into matter, also allows one to combine powder diffraction methods with several sample environments, e.g. It enables determination of the crystalline nature of materials and thereby often chemical compositions, particle size and the nature of defects can be investigated (Klug & Alexander, 1974 ▶ Mittemeijer & Scardi, 2004 ▶ Dinnebier & Billinge, 2008 ▶ Guinebretière, 2013 ▶). Powder diffraction is one of the most important material characterization methods. 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. At higher angles the whole linear detector is used and the data collection remains fast. The presented algorithm selects an adaptive range of channels of the linear detector at low angles, resulting in increased resolution. An easy approach to limit the resolution-degrading effects is presented. Because of the straight nature of most modern detectors geometrical defocusing occurs, which heavily influences the line shape of diffraction lines at low angles. In this work the influence of a straight linear detector on the resolution function in the Bragg–Brentano focusing geometry is discussed. This usually goes hand in hand with worse resolution and asymmetric peak profiles. A common way of speeding up powder diffraction measurements is the use of one- or two-dimensional detectors. ![]()
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