3.8

Diffraction Changes

Single Crystal

Instrument View

  • The instrument view has been modified to optionally display relative peak intensities on a qualitative scale. The intensities are indicated by markers of different size. The option is found in the “Render”-tab of the instrument view:
../../_images/InstrumentViewIntensities.png

Algorithms

  • There is now an algorithm LoadCIF which loads crystal structure information from a CIF-file into the sample associated to a workspace. Optionally, a UB-matrix can also be loaded from the file.
  • PredictPeaks has been modified to optionally use the crystal structure information to calculate structure factors for the predicted peaks.
  • SortHKL has received a major speedup for calculation of statistics for PeaksWorkspaces with large numbers of peaks and/or high symmetry.

Powder Diffraction

  • New algorithm PDToPDFgetN which converts events files into suitable PDFgetN files.
  • Various fixes and optimizations to make SNSPowderReduction run faster.
  • New documentation page for the ISIS Powder Diffraction with comprehensive workflow-diagrams and usage example.
  • Many small changes made to the ISIS Powder Diffraction script to enable smoother process, which can be discovered on the ISIS Powder Diffraction documentation page.

Crystal Improvements

  • CrystalStructure has been exposed to Python, along with ReflectionGenerator. Both can be used together to calculate HKL-lists as well as d-spacings and structure factors for a given crystal structure. Usage examples are included in a new documentation page.
  • Alternative settings for space groups have been added, including different cell choices for monoclinic space groups, rhombohedral settings for trigonal space groups and origin choices. The documentation has been updated.
  • There is now a clear separation between crystal- and lattice system within PointGroup. This is relevant for trigonal space groups which can belong either to the rhombohedral or the hexagonal lattice system. This change affects the functions LatticeFunction and PawleyFunction, as well as the algorithm PawleyFit, which now use lattice system instead of crystal system.
  • CorrectIfOnEdge option was added to IntegratePeaksMD to estimate the part of the peak off the detector edge.

Updates for POLDI routines

Bugfixes

  • PoldiFitPeaks2D now correctly refines hexagonal cell parameters for trigonal structures in hexagonal setting (details)

Engineering Diffraction

  • New functionality has been integrated in the Engineering diffraction GUI (and the Engineering diffraction algorithms have been updated and extended wherever needed):
    • Multi-run processing
    • Multi Runs Focus Mode combo-box enables user to carry out focusing process by focusing Individual Run Files Separately or by focusing the Sum Of Files
    • Stop Focus button terminates the multi-run focussing process
    • Basic support for event mode.
    • Advanced calibration modes (cropped and texture).
    • Additional plotting options for calibration and focusing results.
    • A default calibration for EnginX is included with Mantid.
    • Support for several output file formats (GSAS, OpenGenie, XYE format).
    • GUI has been made further more interactive and customisable; user can now disable or enable particular functionality and features upon preference
engg_calib_tab engg_focus_tab engg_preproc_tab

Imaging

  • The tomography reconstruction interface now supports the new functionality introduced in recent versions of the reconstruction tools Tomopy and Astra Toolbox.
  • Scripts to aggregate energy bands have been added.
  • Support for running third party tomographic reconstruction tools locally.
  • The GUI now provides an interface (new tabs) to simplify the following tasks:
    • set up pre-processing steps and filters.
    • visualize sequences or stacks of images and select regions of interest and regions for normalization.
    • browse results produced by reconstruction tools and open them up in external 3D visualization tools.
tomo_gui_snapshot_tab4 tomo_gui_snapshot_tab3 tomo_gui_snapshot_tab1

Full list of diffraction and imaging changes on GitHub.