I am doing rietveld refinement of my hydrated cement paste samples and while varying various parameters I even sometime use flat plate absorption. That option brings about significant changes in proportions of various phases. Just wondering when is flat plate absorption parameters required to be used in the refinement process? I am using highscore plus software and the various phases that are present in crystalline form in my hydrated cement paste samples are Quartz, Mullite, Calcite, Portlandite, Ettringite, Gypsum, alite and Larnite
I suspect that you use Bragg-Brentano geometry. This case is particularly sensitive to the thickness of a sample. Check the linear absorption coefficients for respective minerals in your sample. If you cannot find values then just check mass attenuation coefficients and the bulk density of the mineral. You will see that for thicker specimens, more transparent minerals will give stronger signal due to the greater penetration (hence illuminated volume). In order to better understand the what you do you should also read about the absorption and its dependence on the path length, angles and wavelength.
Thanks Andrej, i'll look for material on absorption. Just wondering if you suggestions about any good book/article covering absorption aspect?
There are many good books on this old menace of many diffraction studies. I have here "Two-Dimensional X-ray Diffraction" from Bob He that is really nice and compact compendium on all aspects of diffraction (frequently advertised by Buker). On the net you can also find numerous lecture materials form various seminars. Im sure you will find something suitable to guide you to more specialized materials. Here are some examples:
https://www.google.de/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0ahUKEwihxM6kvNHMAhVsIsAKHRJUDn8QFggcMAA&url=http%3A%2F%2Fwww.icdd.com%2Fppxrd%2F09%2Fpresentations%2F2010-ppxrd-he.pdf&usg=AFQjCNFqwqrt-KAKKfVH6IZ4yPWMt0lFmw&sig2=i81dwIIGjiAvAdqMZcm6qA
https://www.google.de/url?sa=t&rct=j&q=&esrc=s&source=web&cd=6&ved=0ahUKEwihxM6kvNHMAhVsIsAKHRJUDn8QFgg6MAU&url=http%3A%2F%2Fwww2.physics.ox.ac.uk%2Fsites%2Fdefault%2Ffiles%2FCrystalStructure_fullnotes6.pdf&usg=AFQjCNEQli0n429-iViYnYRh008jbQ5X1w&sig2=H0wbDdH4VmOt8YVe0xTstw
http://profex.doebelin.org/wp-content/uploads/2014/02/Lesson-3-Sample-Preparation-and-Problems.pdf
- Badges
- Science topic
- Similar topics
- Engineering
- Civil Engineering
- Construction
- Construction Engineering