Joint fit: PbSO₄, neutron and X-ray¶

The same staged fit as the Python and Command line tutorials, in the app. Its structure and experiment come from EasyDiffraction's collection with Load ▾ From web…, and each stage frees its parameters in the Parameters table on Analysis before the fit.

Create a project¶

Press Start on Home, then Create a new project, and give it a name.

Load the structure¶

On Structure, choose Load ▾ From web…, search for each entry by its id and click it:

• pd-neut-xray-cwl_pbso4-d1a-lab-pbso4

Load the experiments¶

On Experiment, choose Load ▾ Full experiment From web…, search for each entry by its id and click it:

• pd-neut-xray-cwl_pbso4-d1a-lab-d1a
• pd-neut-xray-cwl_pbso4-d1a-lab-lab

Set the minimizer¶

On Analysis → Extra, set the Minimizer as the case's project does: the Shift/s.u. stop rule and room for more iterations.

Start with nothing free¶

On Analysis, open the Free column header of the Parameters table and fix every parameter, so the stages below free one group at a time.

Scales, 2θ zeros and cell¶

Filter the Linked structures parameters of d1a and lab, choosing each in the datablock filter using the category filter, the Instrument parameters with calib in their name of d1a and lab, choosing each in the datablock filter using the category filter and the name filter and the Cell parameters of pbso4, choosing each in the datablock filter using the category filter, click the Free column header and choose Free · all, then press Fit in the status bar.

Backgrounds¶

D1A's points and the laboratory pattern's Chebyshev terms.

Filter the Background parameters using the category filter, click the Free column header and choose Free · all, then press Fit in the status bar.

Peak widths¶

Filter the Peak broadening parameters of d1a and lab, choosing each in the datablock filter using the category filter and the Peak mixing parameters with eta_0 in their name of d1a and lab, choosing each in the datablock filter using the category filter and the name filter, click the Free column header and choose Free · all, then press Fit in the status bar.

Peak asymmetry, D1A¶

The D1A pattern's four Bérar–Baldinozzi terms.

Choose d1a in the datablock filter, then filter the Peak asymmetry parameters using the category filter, click the Free column header and choose Free · all, then press Fit in the status bar.

Peak asymmetry, laboratory¶

The laboratory pattern's first-order terms.

Choose lab in the datablock filter, then filter the Peak asymmetry parameters using the category filter, click the Free column header and choose Free · all; then type a1 in the name filter and choose Fixed · all in the same menu; then type b1 in the name filter and choose Fixed · all in the same menu, then press Fit in the status bar.

Atom positions¶

The neutron and X-ray patterns together see the oxygen as well as the lead, so all free coordinates fit at once.

Choose pbso4 in the datablock filter, then filter the Atomic coordinates parameters using the category filter, click the Free column header and choose Free · all, then press Fit in the status bar.

Displacements¶

Choose pbso4 in the datablock filter, then filter the Atomic displacement parameters using the category filter, click the Free column header and choose Free · all, then press Fit in the status bar.

Correlations¶

The Correlations view on Analysis shows which fitted parameters move together.

Report¶

The Report page collects the structure, the experiment and the fit.