GSAS Nickel example using EXPGUI (part 7)
7. Setup for Least-Squares Refinement
Before the model can be refined to better fit the data, one must decide on the order of parameters to be optimized. When starting with a new model it is a good idea to refine the scale factors for each histogram and the background terms before refining any structural parameters. So below EXPGUI will be used to check which parameters are set to be refined.
We then check each histogram from the Histogram pane, and see that the background function has been set to type 4, with 4 terms, as recommended in the tutorial, and that no diffractometer constants will be refined (above and below).
We can quickly confirm that the scale factors for the two
histograms will be refined on the Scaling pane
(above and below).
Finally we check that no profile terms are being refined on the Profile
panes.
(above and below).
(.EXP Snapshot:
nickel7.exp
)
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