I recently submitted a paper where I stated the fabrication of a single-phase material. Using the MD Jade software for the XRD analysis, I matched all the peaks with the PDF of that very respective material. I also performed Rietveld refinement and whole pattern fitting, though I did not submit those data initially. Now the reviewer wants a table with refinement results to prove goodness of fit and insert the crystallographic lattice, ions positions and other results. I went through the article R factors in Rietveld Refinement : How Good is Good enough. Any sort of guidance would be appreciated. Thank You.
If your R value is really that high I have strong doubts that the solution is correct. However, I have trivial question: you said that you produced a single crystalline material. How did you performed your polycrystalline analylis? Grinding or milling the phase?
Regarding R values: they are in maximum a number which described deviations. Even an excellent R value does not prove that your structure is correct. It only tells you that the simulated results matches the experimentally collected signal. The solution might be not unique (it is only ONE (!) number) and also your experimenal data can be falsified. However, you should perhaps tell a bit more about the crystal, show the data, and let us discuss about the reliability of your solution and conclusions.
Thank You for your answer.
The material we produced is a single-phase material as all the peaks match with the obtained XRD analysis. However, the peak intensity doesn't always match with the simulated data. That is one of the reasons why we have a higher R value.
Sorry P. Sikder, I did not carefully read your description. My mistake, I apologize.
The peak positions only correlate to the mathematical abstraction of the crystal lattice. It defines all peak positions but does not say anything about the crystal structure, i.e. the actual phase. Only the intensities give you some kind of confirmation that the discovered phase is actually correct. If this is not correct as in your case, two possible explanations exist. A) your phase is incorrect, and B) there are some other factors affecting the detected intensities. The most probable are the grain size (too big), or texture (preferred orientation). The first problem can be easily solved by a new grinding and measuring. The second could be a bit more complicated but you ca move or tilt the sample during the measuring in order to find out whether the intensities change. If they do it is certainly B). If the intensities do not vary, your structure is wrong.
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