WK.02   GSAS-II Workshop

Building on the experience gained in the long term development and support of GSAS and the associated EXPGUI graphical interface, GSAS-II has been newly developed as a new crystallographic package that integrates a computation framework, display graphics and a modern graphical user interface. The package is intended to handle crystallographic problems of all sizes, with neutron and/or x-ray data and with powder or single-crystal data, as is currently available in GSAS. Moreover, GSAS-II also incorporates tools for crystal structure solution and powder data reduction. The code is open source and extensible, written using the modern object-oriented Python language. This workshop will introduce the attendees to the use of GSAS-II for the reduction, solution and refinement of crystallographic data, with particular emphasis on powder diffraction data. The Workshop will cover area detector data reduction, powder peak picking and fitting, powder pattern indexing, peak intensity extraction via Pawley methods and then structure solution by charge flipping. After structure completion via Fourier methods, the workshop will cover use of GSAS-II for Rietveld refinement. All software needed to install and run the software is freely available and runs on Windows, Mac and other Unix based operating systems. Attendees will be required to bring their own laptops with the software already downloaded. GSAS-II can be found athttps://subversion.xor.aps.anl.gov/trac/pyGSAS; we recommend use of the prepackaged Python system "EPD Free" available from http://www.enthought.com/products/epd_free.php, but any version 2.6 or 2.7 Python distribution including the packages required by GSAS-II is expected to work (see our pyGSAS site for details).



Robert von Dreele, Argonne National Lab, [email protected]

Brian H. Toby, Argonne National Lab, [email protected]


Workshop Fee:
Student or Postdoc - $75
All Others:  $100