Crystallite Size & Microstrain - Part 2 - Williamson Hall Plots - HighScore Plus - Panalytical

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  • Опубликовано: 26 ноя 2024

Комментарии • 22

  • @johnnystroud4150
    @johnnystroud4150 4 года назад +1

    Very nice presentation. Thank you!

  • @bmmelo2oo7
    @bmmelo2oo7 3 года назад +1

    Thank you for your contribution, Dr. Michael. Very helpful video. I would like to ask you a question regarding the size/strain standard. We use the LaB6 NIST 660c standard, however, the profile fitting is not great and the shape of the curve fitting (seen in the halfwidth plot - FWHM statistics or Broadening) also does not follow a Caglioti-type shape. To solve this, we performed the profile fit with the “Use shape function” and “Asymmetry Type - Split Width and Shape” options in the Refinement control. My question is, can we use this options in the profile fitting? Or will they change the procedure and result in bad/misleading Caglioti parameters? (The 6 parameters which will be used to calculate the U, V, and W). Thank you in advance.

    • @IAMMDiffractionFacility
      @IAMMDiffractionFacility  3 года назад +1

      If I'm not mistaken, you can apply asymmetry options, but you need to use them for both the standard and the sample of interest. Let me ask though, is your asymmetry worse at lower angles of 2theta? What soller slits are you using? It's always better if you can correct for fitting problems on the hardware side of things rather than refining additional parameters in analysis, hence my questions. Sometimes though, you are left with no other choice than refining the additional parameters.

  • @flemirbingo6185
    @flemirbingo6185 Год назад +1

    Dear Sir, I don't have the Solver Tolerance function the Global Var Table. May I ask which version is your software? 3.0 is currently installed on my lab's computer, I don't know if I should update it.

    • @IAMMDiffractionFacility
      @IAMMDiffractionFacility  Год назад

      I am currently running version 4.9. If you can't find the solver tolerance, I wouldn't worry too much about it. Sometimes I change it, sometimes I don't. I only really change it if I have a very simple diffraction pattern.

    • @flemirbingo6185
      @flemirbingo6185 Год назад

      @@IAMMDiffractionFacility Thank you very much, sir. I currently have another problem, that is, when I import my XRD data, I couldn't click the strip Kα2 button, but if I import the tutorial data, the button works fine. Could you tell me why this happens?

  • @Rumkeez
    @Rumkeez 3 года назад +1

    Really helpful video! I'm using Highscore 3.0.0. and that version doesn't have solver tolerance under general properties tab. Any idea where I can find it or what's the equivalent parameter to make the fit more demanding?

    • @IAMMDiffractionFacility
      @IAMMDiffractionFacility  3 года назад

      Thank you, and my apologies for the slow reply! Unfortunately, I'm not sure how to change something like solver tolerance in that version. However, whatever default value is set will probably work just fine.

  • @samrattamuly8157
    @samrattamuly8157 2 года назад

    How much microstrain should we ignore. And can we replace crystallite size with grain size incase it is big enough to find dislocation strengthening

  • @gauravgupta6097
    @gauravgupta6097 3 года назад +1

    Great Work... very helpful!!

    • @IAMMDiffractionFacility
      @IAMMDiffractionFacility  3 года назад

      Thank you! I'm glad it was helpful!

    • @gauravgupta6097
      @gauravgupta6097 3 года назад +1

      @@IAMMDiffractionFacility I have some problem in indexing my pattering as it is very complex with numerous peaks of different phases and shifts might also be there. Can you Please help .

    • @IAMMDiffractionFacility
      @IAMMDiffractionFacility  3 года назад

      How are you hoping I can help? Do you have any specific questions? Why do you think there may be shifts?

  • @ousamamahroua1151
    @ousamamahroua1151 3 года назад +1

    Hello thank you. this work is very useful . my question is , how i can export this result to originlab especially the W-H PLOT

    • @IAMMDiffractionFacility
      @IAMMDiffractionFacility  3 года назад +2

      Thank you for the kind words! If you want to export the WH plot, I suggest going to your peak list (which is right above the WH plot). Right-click in the peak list and choose "Customize Peak List." You'll see a new window appear titled "Customization," and look for the "Struct. B [o2theta]" line. Hold the left button on the mouse while over it and drag it to the position that you want on the column headline at the top of the peak list. You'll see the new column appear there, but it will be empty. Close the little "Customization" window, and you should see the Struct. B values appear.
      Next, left-click in the peak table, hit Control-A on the keyboard, hit Control-C, and then paste it in Excel or Origin. You should now have everything you need to recreate the plot in Origin. If you look at the axes of the WH plot in HighScore, it will tell you what you need to calculate and plot in Origin.
      Let me know if this works for you or if you have any questions.

    • @choonsilin5441
      @choonsilin5441 11 месяцев назад

      @@IAMMDiffractionFacility Hi sir, may I know what is Struct. B corresponding to? FWHM? Because from the basic W-H plot, the y-axis is beta cos theta, how about this Struct. B? Any equation to get Struct. B?

  • @ianrosbottom8243
    @ianrosbottom8243 2 года назад

    Hello. Thanks for the great videos. I want to use the Williamson Hall approach for organic materials, where the main peaks are at much lower 2 theta angles and peaks frequently overlap. Is it still appropiate to use a standard such as aluminum for my standard reference scan, even though I think it's lowest peak is around 20 degrees 2 theta? Should I also be collecting these data sets in transmission with long exposure times to get the best data possible for this? Many thanks

    • @IAMMDiffractionFacility
      @IAMMDiffractionFacility  2 года назад +2

      Hi Ian, my apologies for the slow reply! I typically study inorganic materials, so my experience with organic samples is much more limited. I feel that there are varying degrees of peak overlap. At times, peaks can overlap but still be easy to deconvolute. Other times, you can have overlap where the deconvolution is not so clear. Obviously, the better/easier it is to deconvolute the peaks, the more accurate your analysis will be.
      You also need to know if all peaks in your pattern are from a single phase. If you have multiple phases in your sample, you will need to deselect the peaks of all phases except one for the analysis of each phase.
      Regarding standards, the proper choice is to use one that has peaks that begin at lower values of 2theta compared to your peaks. I'm honestly not sure what standard would be good for this as the lowest 2theta angle that NIST provides is ~21 degrees with LaB6 (if I'm not mistaken). Whatever you use, it needs to have no broadening due to crystallite size and/or microstrain. If you can't find anything that will work well, I'm guessing that using something like LaB6 will still get you in the ballpark of the correct answer, especially if your peaks are much broader than the peaks from the standard.
      Regarding transmission, that may help. When in doubt, my suggestion is to just try it both ways and determine which one produces nicer results. Regarding exposure time, the general rule of thumb is that multiplying the time by 4 will reduce the noise by half.

  • @rahulkashyap2666
    @rahulkashyap2666 2 года назад

    Thank you for the video. One question: Will changing the detectors (eg: 1D to 2D) change the instrument broadening?

    • @IAMMDiffractionFacility
      @IAMMDiffractionFacility  2 года назад

      Good question. I don't believe it will change the instrumental broadening as you aren't really changing the beam itself, but I would recommend trying it both ways once to make sure as I don't recall trying it myself.

  • @sauravti
    @sauravti 8 месяцев назад +2

    Awesomeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee