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Topas is a powerful suite of software written by Alan Coelho for the analysis of powder diffraction data. Bruker ( market the original version of topas which comes with a full graphical user interface. An academic-only version is also available from Alan Coelho.

Topas allows you to:

  • analyse constant wavelength and energy dispersive X-ray data
  • analyse constant wavelength and time of flight neutron data
  • perform Rietveld/Pawley/individual reflection fitting
  • index powder diffraction data
  • solve structures by simulated annealing
  • perform isodisplace distortion mode refinements
  • etc

You can find lots more information about topas on various web sites. Try:
John Evans' site: Alan Coelho's site: Bruker's site:

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