Editing X-ray crystallography (section)

=== Applied computational data analysis ===
The use of computational methods for the powder X-ray diffraction data analysis is now generalized. It typically compares the experimental data to the simulated diffractogram of a model structure, taking into account the instrumental parameters, and refines the structural or microstructural parameters of the model using [[least squares]] based minimization algorithm. Most available tools allowing phase identification and structural refinement are based on the [[Rietveld refinement|Rietveld method]],<ref>{{Cite journal |vauthors=Rietveld HM |date=1969-06-02 |title=A profile refinement method for nuclear and magnetic structures |journal=Journal of Applied Crystallography |volume=2 |issue=2 |pages=65–71 |bibcode=1969JApCr...2...65R |doi=10.1107/S0021889869006558 |doi-access=free}}</ref><ref>{{Cite book |title=The Rietveld Method |vauthors=Young RA |date=1993 |publisher=International Union of Crystallograhy |isbn=0198555776 |location=[Chester, England] |oclc=26299196}}</ref> some of them being open and free software such as FullProf Suite,<ref>{{Cite web |title=IUCr |url=https://www.iucr.org/resources/commissions/powder-diffraction/newsletter |access-date=2019-04-06 |website=www.iucr.org |archive-date=2019-04-06 |archive-url=https://web.archive.org/web/20190406103706/https://www.iucr.org/resources/commissions/powder-diffraction/newsletter |url-status=live }}</ref><ref>{{Cite web |title=Fullprof |url=https://www.ill.eu/sites/fullprof/ |access-date=2019-04-06 |website=www.ill.eu |archive-date=2019-04-02 |archive-url=https://web.archive.org/web/20190402200238/https://www.ill.eu/sites/fullprof/ |url-status=live }}</ref> Jana2006,<ref>{{Cite journal |vauthors=Petříček V, Dušek M, Palatinus L |date=2014-01-01 |title=Crystallographic Computing System JANA2006: General features |journal=Zeitschrift für Kristallographie – Crystalline Materials |volume=229 |issue=5 |pages=345–352 |doi=10.1515/zkri-2014-1737 |issn=2196-7105 |s2cid=101692863}}</ref> MAUD,<ref>{{Cite journal |vauthors=Lutterotti L |date=February 2010 |title=Total pattern fitting for the combined size–strain–stress–texture determination in thin film diffraction |journal=Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms |volume=268 |issue=3–4 |pages=334–340 |bibcode=2010NIMPB.268..334L |doi=10.1016/j.nimb.2009.09.053 |issn=0168-583X}}</ref><ref>{{Citation |title=Tenth European Powder Diffraction Conference |pages=125–130 |year=2007 |chapter=Rietveld texture analysis from diffraction images |publisher=OLDENBOURG WISSENSCHAFTSVERLAG |doi=10.1524/9783486992540-020 |isbn=9783486992540 |vauthors=Lutterotti L, Bortolotti M, Ischia G, Lonardelli I, Wenk HR}}</ref><ref>{{Cite journal |vauthors=Lutterotti L, Matthies S, Wenk HR, Schultz AS, Richardson Jr JW |date=1997-01-15 |title=Combined texture and structure analysis of deformed limestone from time-of-flight neutron diffraction spectra |journal=Journal of Applied Physics |volume=81 |issue=2 |pages=594–600 |bibcode=1997JAP....81..594L |doi=10.1063/1.364220 |issn=0021-8979}}</ref> Rietan,<ref>{{Cite web |title=Distribution Files for the RIETAN-FP-VENUS Package |url=http://fujioizumi.verse.jp/download/download_Eng.html |access-date=2019-04-06 |website=fujioizumi.verse.jp |archive-date=2019-08-10 |archive-url=https://web.archive.org/web/20190810120240/http://fujioizumi.verse.jp/download/download_Eng.html |url-status=live }}</ref> GSAS,<ref>{{Cite journal |vauthors=Toby BH, Von Dreele RB |date=2013-03-14 |title=GSAS-II: the genesis of a modern open-source all purpose crystallography software package |journal=Journal of Applied Crystallography |volume=46 |issue=2 |pages=544–549 |bibcode=2013JApCr..46..544T |doi=10.1107/s0021889813003531 |issn=0021-8898}}</ref> etc. while others are available under commercial licenses such as Diffrac.Suite TOPAS,<ref>{{Cite web |title=DIFFRAC.SUITE TOPAS - XRD Software, X-ray diffraction |url=https://www.bruker.com/products/x-ray-diffraction-and-elemental-analysis/x-ray-diffraction/xrd-software/topas.html |access-date=2019-04-06 |website=Bruker.com |archive-date=2019-04-02 |archive-url=https://web.archive.org/web/20190402174859/https://www.bruker.com/products/x-ray-diffraction-and-elemental-analysis/x-ray-diffraction/xrd-software/topas.html |url-status=live }}</ref> Match!,<ref>{{Cite web |title=Match! – Phase Identification from Powder Diffraction |url=http://www.crystalimpact.com/match/ |access-date=2019-04-06 |website=www.crystalimpact.com |archive-date=2019-04-02 |archive-url=https://web.archive.org/web/20190402175018/http://www.crystalimpact.com/match/ |url-status=live }}</ref> etc. Most of these tools also allow [[Le Bail method|Le Bail]] refinement (also referred to as profile matching), that is, refinement of the cell parameters based on the Bragg peaks positions and peak profiles, without taking into account the crystallographic structure by itself. More recent tools allow the refinement of both structural and microstructural data, such as the FAULTS program included in the FullProf Suite,<ref>{{Cite journal |vauthors=Casas-Cabanas M, Reynaud M, Rikarte J, Horbach P, Rodríguez-Carvajal J |date=2016-12-01 |title=FAULTS: a program for refinement of structures with extended defects |journal=Journal of Applied Crystallography |volume=49 |issue=6 |pages=2259–2269 |bibcode=2016JApCr..49.2259C |doi=10.1107/S1600576716014473 |issn=1600-5767}}</ref> which allows the refinement of structures with planar defects (e.g. stacking faults, twinnings, intergrowths).