We're dealing with Glass Ceramics but crstallite size in XRD is not matching with TEM.
In XRD, you measure the size of coherently diffracting domains (coherency length), not strictly the same as grain size. If your grains have defects/stacking faults etc the coherency length can be much smaller than the actual grain size.
Or, as the prvious poster said, it can be the instrument broadening. 600 nm grain size should give a negligible broadening.
Did you substract the instrument function before applying your FWHM analysis?
If your TEM measured domain size is right there shouldn't be almost no structural broadening except the instrumental contribution.
In XRD, you measure the size of coherently diffracting domains (coherency length), not strictly the same as grain size. If your grains have defects/stacking faults etc the coherency length can be much smaller than the actual grain size.
Or, as the prvious poster said, it can be the instrument broadening. 600 nm grain size should give a negligible broadening.
Why do you expect them to match? They're measuring totally different particle properties.The Scherrer equation in XRDLB is not applicable at 600 nm
Thank you Dr. Dominique for your comment. I've applied the background correction as well. Further regarding Prof. Eklund comment I found it interesting since TEM and XRD studies are complementary hence there's possibility of getting greater particle size is acceptable. Dr. Rawle thanks for your comment and if possible kindly share some articles that deals with the applicability of Scherrer equation. Thank you.
"What is the probable reason for getting 600 nm NC in bulk TEM whereas XRD Scherrer equation gives us 50 nm as crystallite size?"
If you share more information about the chemistry and processing history for your sample, you should get better feedback from the RG expertise. Posting your XRD data and TEM micrographs will make it more interesting to the rest of us as well :-)
https://www.flickr.com/photos/85210325@N04/10221065324/in/album-72157645018820696/
"K is a dimensionless shape factor, with a value close to unity. The shape factor has a typical value of about 0.9, but varies with the actual shape of the crystallite;"
Is the "shape factor" an empirical parameter? "woodoo XRD" or is there a method to the choise for the value?
Can one detect an average shape factor better using supplementary SEM, TEM or 2D XRD observations?
Besides, preferred orientation & defect morphology will affect the "shape factor" also.
Can these individual components controlling the changes in the shape of the "Bragg Profile" be potentially deconvoluted?
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