Dear François, I can think of no reason for a correlation between your peak shape and your resultant amorphous content, unless somehow the super-Lorentzian peak shape is not providing accurate intensities. Have you tried your fit with another peak shape or a fundamental parameters approach? I assume that you used an "infinitely thick" specimen and modeled the internal standard well.
I agree with Reinhard, generally 40% amorphous will be visible, although if you are unfamiliar with the scattering from partially to completely disordered or amorphous materials, it could be possible to miss this much. I will send you separately a reprint with some example patterns with increasing amounts of added amorphous material, wherein you will see that even 50% amorphous is not "extremely" obvious. Best of luck, David On 3/3/2021 7:34 AM, François Goutenoire wrote: This message was sent from a non-IU address. Please exercise caution when clicking links or opening attachments from external sources. ------- Dear Rietveld users, I have some industrial compound presenting a strong hyper-Lorentzian peak shape (eta=1.1 with HighScore). When we calculate the amorphous content after an internal standard addition, the result is 40%. The micro-absorption effect has been minimized (mu of the internal standard is closed to the compound). But with some electronic transmission analysis no amorphous is observed. The question is : Does a strong hyper-Lorentzian peak shape could influence quantitative analysis ? François ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Please do NOT attach files to the whole list <alan.he...@neutronoptics.com><mailto:alan.he...@neutronoptics.com> Send commands to <lists...@ill.fr><mailto:lists...@ill.fr> eg: HELP as the subject with no body text The Rietveld_L list archive is on http://www.mail-archive.com/rietveld_l@ill.fr/ ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ -- David L. Bish Indiana University Molecular Structure Center Chemistry Building, A421 800 E. Kirkwood Ave. Bloomington IN 47405-7102 812-855-2039
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