How can I figure out amorphous region, crystalline region and total intensity?
Thanks Anna Pooova. but I am using Origin. Can we do it by Origin?
Dear Pratiksh, what samples do you study?
Can you show your XRD-pattern?
My sample is lignocellulose material. I got FWHM and height for these points. Can I say FWHM as area covered by that peak?. if not I was thinking of calculating on the basis of peak height. (CI200- CI Amorphous)/CI200. Please do correct me if I am going wrong. Thanks.
The pattern could be moisture or amorphous phase. If you dry powder, XRD peaks would be better. Good luck.
This link may be help you.
http://rruff.info/
Estimating the amorphous content in XRD is not very straight-forward, but here you have something that might help you:
http://www.americanpharmaceuticalreview.com/Featured-Articles/36758-Approaches-to-Quantification-of-Amorphous-Content-in-Crystalline-Drug-Substance-by-Powder-X-ray-Diffraction/
http://www.icdd.com/ppxrd/12/presentations/P30-Arnt-Kern-ppxrd-12.pdf
It is not quite so straightforward as taking FWHM from two points.
In your first pattern you have three separate types of crystallinity. The first is the underlying rise and fall of the background (10-50), this is the true X-ray amorphous phase. The second is the group of relatively broad peaks that indicate poorly crystalline material (7 and 22). The third is the group of sharp peak that represent the crystalline phase(s). It is possible to measure these by any curve fitting routine and finding areas under the curve for each group, this will give you ratios of the components.
The second graph is a mix of amorphous and poorly crystalline, and a similar approach could be taken, but in this case is a little more difficult to deconvolve the poorly crystalline broad peaks from the underlying background. Full pattern fitting may help.
In order to do absolute measures you would need to use a standard spike. Other methods are available.
Indeed, defining crystallinity might be quite problematic and care need to be taken so that the variations in the measurements parameters do not overrule the real results. In any case, appropriate crystalline reference is needed. There is also several other methods that can be utilized:
http://www.sciencedirect.com/science/article/pii/S0032591006001860
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