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<font face="serif">Good evening,<br>
<br>
I've got a few questions concerning the way RMCprofile handles
instrumental resolution.<br>
Premise: I'm currently trying to understand why both the D(r) and
F(Q) functions calculated in my RMC runs</font><font face="serif"><font
face="serif">, apparently,</font> don't match very well the
decay of the experimental D(r) and F(Q). As a result, unwanted
disorder might be introduced in the model, just like the footnote
in p.10 of the manual of v.6.5.2 points out. This is best observed
in the D(r) fit residual at different stages of the calculation,
in which the RMC D(r) fits more accurately either the low-r range
or the high-r range depending on the disorder in the model.<br>
<br>
1. <br>
Initialising the Bragg refinement of TOF data produces the </font><tt>.inst</tt><font
face="serif"> file containing one block of diffractometer
constants and profile parameters for each of the detector banks.
During the RMC run, the Bragg fit of the histogram I selected in
the </font><tt>get_gsas_bragg</tt><font face="serif"> routine
(say histogram 4 from bank 4) will obviously be based on the
parameters of bank 4. But since I'm not declaring which detector
banks were used for getting the total scattering data (and the
respective fits are not affected by histogram choice) does RMC
take into account all the detector banks provided in the </font><tt>.inst</tt><font
face="serif"> file when fitting to the D(r) and F(Q)? <br>
<br>
2.<br>
If so, is this behavior enabled by the </font><tt>RESOLUTION_CONVOLUTION</tt><font
face="serif"> flag? Is it ignored otherwise? <br>
Can the resolution correction described in the <i>MCGRtof</i>
paper be applied as suggested in the manual?<br>
<br>
3.<br>
Should </font><font face="serif"><font face="serif">I include in
the </font><tt>.inst</tt><font face="serif"> file </font>the
detector banks that were ignored for the sake of practicality
during the Rietveld refinement? </font><font face="serif"><br>
<br>
4.<br>
Is the F(Q) endpoint the part of the input defining the Qmax for
PDF calculation?<br>
<br>
<br>
Thanks,<br>
Stefano<br>
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