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<span style="margin:0px;font-size:12pt">Hi,</span>
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<div style="margin:0px;font-size:12pt">I am working on the Rietveld refinement using GSAS-ll in order to get lattice parameter and phase fraction of the phases observed. However, when I conduct the refinement, I got some peaks, calculated based on the crystal
structure in the cif file, even though the peaks are not observed from the sample evaluated. I think it affects the lattice parameter and phase fraction (t<span style="margin:0px;background-color:rgb(255, 255, 255);display:inline !important">he intensity of
these peaks is not high compared to the main peaks)</span>. <span style="margin:0px">I am wondering about how I can solve this "overfitting" problem. I was thinking about excluding the specific 2theta region where the peaks, appearing </span><span style="margin:0px">based
on the crystal structure in the cif file,</span><span style="margin:0px"> are located, but I am not sure if it is possible. I would appreciate for any help on this problem.</span></div>
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<div style="margin:0px;font-size:12pt">Thanks.</div>
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<div style="margin:0px;font-size:12pt">Sincerely,</div>
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<div style="margin:0px;font-size:12pt">Purdue University</div>
<span style="margin:0px;font-size:12pt">Gyuchul Park</span><br>
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