Demos¶
Single crystal data reduction: peak search¶
This demo shows how to find peaks on the detector using the program Peakfind, and how to visualize the results on the detector and in the reciprocal space. On the detector, the peaks are shown as crosses that must be over the strong peaks collected during the scan. In the reciprocal space, peaks are displayed as small spots that must shown the reciprocal lattice when viewed from a zone axis.
Demo url: Peak search
Single crystal data reduction: UB-matrix determination¶
This demo shows how to find a good orientation matrix from the peaks found by Peakfind, and how to refine this UB-matrix together with instrument parameters as the wavelength and offsets. The possibility of moving all the spots to their equivalent position closest to the origin of the reciprocal lattice is a very simple and efficient strategy to check if the offsets are well refined. The distribution of spots around the origin should be more isotropic and less sparse than before the refinement.
Demo url: UB-matrix determination
Single crystal data reduction: reciprocal space slicing¶
This demo shows how to perform slicing of the raw data in the reciprocal space by specifying a reciprocal lattice plane and its thickness.
Demo url: Reciprocal space slicing
Powder data reduction: preprocessing¶
This demo shows how to process a gamma scan using the program gamma_scan. The example corresponds to data collected at XtremeD. The demo starts by loading the gamma scan, and displaying it in the 2D viewer. The diffraction rings shift as the detector moves. As the scan has been collected at XtremeD, a calibration file is loaded for applying the efficiency correction (in D19 the counts array in the nexus file has been already corrected). When running gamma_scan, some useful information is displayed on the screen. Note how the number of horizontal pixels of the virtual detector is different from the number of the real detector, while vertical pixels remain the same. The angular range of both the real and virtual detectors can be read from the standard output. When gamma_scan finishes, a new nexus file with the the virtual detector counts is automatically loaded in the scan loader and it can be displayed on the viewer just by double clicking on it.
Powder data reduction: integration¶
This demo shows the integration of three gamma scans collected at three different temperatures. The example corresponds to data collected at XtremeD. The first part of the demo shows the preprocessing of the gamma scans. Then, the nexus files created by gamma_scan are integrated using intpow, and the xys files are then visualized with the FullProf suite.