Bugs in GSAS-II-tutorials/RMCProfile-III/RMCProfile-III.htm

Hello,

I have been following the GSAS-II RMCProfile-III tutorial and found a discrepancy at Step 7.

Environment:

After completing the Rietveld refinement, the fit in GSAS-II is excellent (difference curve is essentially identical to the tutorial).

I then used "Operations -> Setup RMC" to generate the RMCProfile input files.

The exported files are:

When I start RMCProfile (before any RMC moves), the initial Bragg agreement is already much worse than shown in the tutorial.

The tutorial reports an initial Bragg fit close to the Rietveld result, whereas I obtain

Bragg Chi^2/npts ≈ 100

immediately after export.

Observations:

The GSAS-II Rietveld refinement is excellent.
The discrepancy is already present before any RMC moves.
Adding FITTED_SCALE to the BRAGG section improves the agreement, but the initial Bragg Chi^2/npts is still around 20.
Using both RECALCULATE and NO_RECALCULATE gives essentially the same result.
XRAY2 profile is used.

Is this expected with the current GSAS-II/RMCProfile versions, or could there be an issue in the GSAS-II export to RMCProfile?

If useful, I can provide the .gpx project and all exported RMCProfile files.

Thank you.

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