Prezado Nelson, You can find CIF files for both alumina and crocoite phases at the Crystallography Open Database (www.crystallography.net) looking for chemical elements.
An excellent set of educational material on Rietveld refinement using GSAS+EXPGUI at the APS-11BM site ( http://www.aps.anl.gov/Xray_Science_Division/Powder_Diffraction_Crystallography/) and additional resources at http://11bm.xray.aps.anl.gov/resources.html. If you don´t have experience with Rietveld analysis and no-one to ask for advice it may be a painful path to walk alone but there are many books that can be of help such as "The Rietveld Method" by RA Young or "Fundamentals of Powder Diffraction and Structural Characterization of Materials" by Pescharsky and Zavalij... but attending a Rietveld course (such as ICDD Clinics for example) may be of help to start. Finally, but maybe of advanced level, be very careful when extracting weight percentages for both phases from your refinements, if you don´t have perfect control or knowledge of particle sizes for both phases, since the huge difference in absorption coefficients among them may make microabsorption an issue on your quantification work. Best of luck Leo 2014-09-05 13:43 GMT-03:00 Nelson <[email protected]>: > Dear rietvelds > > > > I have some samples, all with the same two phases: alumina and crocoite > (PbCrO4) (electrochemical bath). I use Cobalt radiation. Indexing, I use > always the same two ICDD files, 74-0323 for alumina and 73-1332 for > crocoite. I use software High score plus. Can i use the semiquantification > of software for know the quantification of each phase betwen the samples. > > Wuhere i can find the right cif files for this two phases, for introduce > in High score plus and made Rietveld refinement. > > Where i can find a manual or exemples of how to make a rietveld refinement > of this XRD. > > I don´t have experience of rietveld analysis. > > > > Thanks in advances > > Best regrds > > Nelson > > ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ > Please do NOT attach files to the whole list <[email protected] > > > Send commands to <[email protected]> eg: HELP as the subject with no body > text > The Rietveld_L list archive is on > http://www.mail-archive.com/[email protected]/ > ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ > > > -- Dr. Leopoldo Suescun Prof. Agr (Assoc. Prof.) de Física Tel: (+598) 29290705/29249859 Cryssmat-Lab./DETEMA Fax: (+598) 29241906* Facultad de Quimica, Universidad de la Republica ,_. | \ | v- ,' \ | ( \__Montevideo, Uruguay En pleno disfrute del Año Internacional de la Cristalografía 2014 ( http://www.iycr2014.org ), (http://www.cristalografia2014.fq.edu.uy)
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Please do NOT attach files to the whole list <[email protected]> Send commands to <[email protected]> eg: HELP as the subject with no body text The Rietveld_L list archive is on http://www.mail-archive.com/[email protected]/ ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
