Problem Solving with the TOPAS Macro Language: Corrections and constraints in simulated annealing and Rietveld refinement

Pamela Whitfield, Isobel Davidson, Lyndon Mitchell, Siobhan Wilson, Stuart Mills

Research output: Chapter in Book/Report/Conference proceedingConference PaperResearchpeer-review

10 Citations (Scopus)


The TOPAS macro language can be a powerful tool for increasing the capabilities of Xray powder diffraction analysis. New corrections and constraints can be implemented without altering the program s code, allowing for experimentation with new ideas and approaches. Examples are given, exposing the power and flexibility of the macro language to help solving problems with a few lines of code. The use of simulated annealing for structure solution of an organic material from data exhibiting preferential orientation is one example. Another one is about extraction of useful structural information in Rietveld refinement of natural hydrotalcite-group minerals, a problematic case that would normally be regarded as over-parameterized for the data available.
Original languageEnglish
Title of host publicationExtending the Reach of Powder Diffraction Modelling by User Defined Macros
EditorsPaolo Scardi, Robert E. Dinnebier
Place of PublicationPfaffikon Switzerland
PublisherTrans Tech Publications
Number of pages15
ISBN (Electronic)9783038133339
ISBN (Print)9780878492619
Publication statusPublished - 2010
Externally publishedYes
EventTOPAS Users' Meeting 2009: Development and Application of MACROS using the Algebraic Language of TOPAS - University of Trento, Trento, Italy
Duration: 18 Jun 200920 Jun 2009
Conference number: 4th

Publication series

NameMaterials Science Forum
PublisherTrans Tech Publications
ISSN (Print)0255-5476
ISSN (Electronic)1662-9752


ConferenceTOPAS Users' Meeting 2009

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