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Hi Sergey,
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<div class=""> Both LeBail and Pawley fits are not able to determine phase fractions because the scale factors are all arbitrary and thus the phase fractions cannot be refined. However, the reported mass/weight fractions are determined from the unrefined
phase fractions and they are displayed even though meaningless. </div>
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<div class="">Brian<br class="">
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<div class="">On Apr 8, 2020, at 12:58 PM, Sergey Ushakov via GSAS-II <<a href="mailto:gsas-ii@aps.anl.gov" class="">gsas-ii@aps.anl.gov</a>> wrote:</div>
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Greetings! I have a question maybe not specific to GSAS-II but more about Pawley vs Le Bail fitting of powder XRD data.</div>
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I work on high temperature data from laser-heated solid spheroids which rotate in a gas flow in aerodynamic levitator.
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The data are collected in transmission geometry at 6-ID-D at APS. <br class="">
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The rotation is not well controlled since it depends on the shape of each bead formed by melt solidification, i.e., on surface tension, volume change on melting, etc.
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So, sometimes data are very much powder-like and amenable to Rietveld refinement of the structure, but sometimes they are not, and in this case, I do Pawley fit for cell parameters.</div>
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I used to do Le Bail fitting for that in GSAS-I, but I understand that it was replaced by Pawley refinement (although there is an option for Le Bail extraction of intensities?).<br clear="all" class="">
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To my surprise, Pawley fit in GSAS-II yield phase/weight fraction if one turns it on for refinement.
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I thought phase fraction could be correctly refined only from Rietveld? <br class="">
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I would appreciate any comments on this!<br class="">
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Sergey</div>
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<div class=""><font size="2" class=""><span style="font-family:arial,helvetica,sans-serif" class="">--<br class="">
Sergey Ushakov PhD<br class="">
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Staff Research Associate<br class="">
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Peter A Rock Thermochemistry Laboratory and NEAT ORU<br class="">
Rm 4415, <span class="">Chemistry Annex</span></span></font><font size="2" class=""><br class="">
University of California, Davis</font><br class="">
<font size="2" class=""><span style="font-family:arial,helvetica,sans-serif" class=""><span class=""></span></span></font><font size="2" class=""><span style="font-family:arial,helvetica,sans-serif" class="">Davis, CA 95616</span></font><br class="">
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