In the following example, we will use one of the example files
provided with the distribution, Caf2, which is a dual phase
Fluorite/Iron mixture refining against Neutron powder diffraction data.
Note that you can import GSAS, Fullprof and DBWS structure files.
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You can browse through the refinement options and information by
going through the Menu system or by clicking the relevant ICONs. Refined
parameters are obvious by tick mark next to the value.
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To refine, select either the "quick start" icon or go via the
menu based Rietveld, Refine. Select the corresponding dat/data file
that matches up with the input/control file.
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Select requested options such as dynamic plotting, and the number of cycles
per step then select the Start icon.
Select Step to start the refinement cycles; then when completed, Finish to complete the refinement and generate the output files for analysis, Fourier Map Generation, etc.
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Selecting Information, View BV/Summary will provide bond-angle bond-valence
information based on I.D. Brown's code.
************************************************************ Lattice Parameters for Phase 1 a 5.4663( 1) b 5.4663( 1) c 5.4663( 1) alpha 90.0000( 0) beta 90.0000( 0) gamma 90.0000( 0) HISTOGRAM Rp Rwp Rexp GOF RBRAGG 1 5.50 6.68 4.09 2.67 1.68 ATOM x y z Biso N CA .0000( 0) .0000( 0) .0000( 0) .77( 2) .021( 0) F .2500( 0) .2500( 0) .2500( 0) .80( 1) .042( 0) ATOM B11 B22 B33 B12 B13 B23 CA .0000( 0) .0000( 0) .0000( 0) .0000( 0) .0000( 0) .0000( 0) F .0000( 0) .0000( 0) .0000( 0) .0000( 0) .0000( 0) .0000( 0) Bond Distances for Phase 1 Number of atoms in unit cell = 12 ATOM1 ATOM2 DISTANCE ERROR CA - F 2.3670 .0000 F - F 2.7332 .0000 ATOM1 ATOM2 BONDVALENCE COORD CA - F 1.94 8 ************************************************************ Lattice Parameters for Phase 2 a 3.5936( 1) b 3.5936( 1) c 3.5936( 1) alpha 90.0000( 0) beta 90.0000( 0) gamma 90.0000( 0) HISTOGRAM Rp Rwp Rexp GOF RBRAGG 1 5.50 6.68 4.09 2.67 5.05 ATOM x y z Biso N FE .0000( 0) .0000( 0) .0000( 0) .60( 0) .021( 0) ATOM B11 B22 B33 B12 B13 B23 FE .0000( 0) .0000( 0) .0000( 0) .0000( 0) .0000( 0) .0000( 0) Bond Distances for Phase 2 Number of atoms in unit cell = 4 ATOM1 ATOM2 DISTANCE ERROR FE - FE 2.5411 .0000 ATOM1 ATOM2 BONDVALENCE COORD CA - F 1.94 8 |
Select Information, Plot fourier to generate a fourier map based
on the previous refinement run. Any of the phases can be selected, for x, y or z
slices; and Fobs, Fcalc, Fdif, Patterson Obs, Patterson Calc, Patterson Dif.
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You can double the cell by using the menu options Chart, Double
to get a better indication of the repeat unit and/or add Grid lines and/or
select Animate to automatically go through the slices.
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