Dear João Paulo F. Grilo,

you can find FWHM qualitatively using X'pert HighScore plus by open you xrd file and by clicking on "treatment" choose search peaks then accept it, you will find FWHM in the peak list. Microstrain can be calculated quantitatively (%) but first you need profile fitting. please follow this link and read these two articles

I hope that will help!! good luck

Mohammed M. Obeid  

Best Regards

http://prism.mit.edu/xray/oldsite/tutorials.htm

Dear João Paulo F. Grilo,

you can find FWHM qualitatively using X'pert HighScore plus by open you xrd file and by clicking on "treatment" choose search peaks then accept it, you will find FWHM in the peak list. Microstrain can be calculated quantitatively (%) but first you need profile fitting. please follow this link and read these two articles

I hope that will help!! good luck

Mohammed M. Obeid  

Best Regards

http://prism.mit.edu/xray/oldsite/tutorials.htm

Thank you!! Awesome answer!

Dear Mohammed,

I would like to know why profile fitting have to be runned. Further more, Peak list will be changed after profile fitting, and I wonder  which position and FWHM should be used as peak data?

Thank you very much.

Sincerely yours

Dear Mohammed,

thank you so much for perfect answer, but that was my question too, why we need to fit the profile?

Thank you.

Dear researchers,

I must be careful to answer this kind of question. There are many parameters that must be considered related to the type of fitting. The basic concept is to minimize the difference between the measured and calculated diffraction pattern (yobs-ycal), using profile fitting analysis such as ( Rietveld) by different profile function (voigt, ... etc). Considering peak shape, peak width (u,v,w), unit cell parameters, space group, background, intensity and peak position  to minimize the difference between (yobs-ycal) and get GOF less than 10%. We must do fit profile, because there many parameters effected the measured diffraction pattern, these parameters related to x-ray diffractimeter and sample such as absortion, diffraction optics effects, instrumental factors, preferred orientation.  After fitting, peak position will change and many other parameters will change too. I hope that will help. you can read about quantitative analysis using different types of profile fitting analysis (Rietveld, lebail) to get more information.

best regards.  

,http://pd.chem.ucl.ac.uk/pdnn/refine1/rietveld.htm

thanku