There is material that is partly amorphous. An amount of amorphous phase has changed during thermal treatment. So, is it possible to find this change (or better absolute composition, amorphous/crystal ratio) quantitatively from XRD data?
We certainly can use XRD for this purpose. I and others have been dong this for some 30 years using Retveld analysis in which absolute phase levels are determined by the 'external standard' phase analysis method which is now available through programs High Score and Topas - see O'Connor and Raven (1988), Powder Diffraction, 3, 2-6 for method description.
Examples described in the literature include - Suherman, van Riessen, O'Connor and Li (2002), Powder Diffraction, 17, 178-195 [Determination of amorphous phase in Portland cement clinker]
In addition to the external standard method, we can work with an internal standard, but I strongly recommend the external standard method which does not require mixing the chosen standard with the test sample.
Regards.
Brian O'Connor
As far as I know, only if you have the same amorphous substance and make a mixture for calibration. Otherwise, too many different influences affect the background part.
There is a nice page about this topic:
http://www.xrd.us/technote/amorphous%20content%20determination.htm
I think calibation is the way to go. I used this method for cellulose. I had pure cellulose as a reference and recorded spectra with different degree of crystallinity. Finally I used deconvolution of peaks in order to find the amorphous part.
We certainly can use XRD for this purpose. I and others have been dong this for some 30 years using Retveld analysis in which absolute phase levels are determined by the 'external standard' phase analysis method which is now available through programs High Score and Topas - see O'Connor and Raven (1988), Powder Diffraction, 3, 2-6 for method description.
Examples described in the literature include - Suherman, van Riessen, O'Connor and Li (2002), Powder Diffraction, 17, 178-195 [Determination of amorphous phase in Portland cement clinker]
In addition to the external standard method, we can work with an internal standard, but I strongly recommend the external standard method which does not require mixing the chosen standard with the test sample.
Regards.
Brian O'Connor
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