The following is used as an example of using the Rietbasic macro languate to perform automatic refinement runs on a large number of near identical data files (preferably in a numeric sequence (any Rietica supported data format is acceptable) - blah01.cpi, blah02.cpi, blah03.cpi, etc). Click here to download the example script and data files. In the above example data (Le Bail fitting to perform unit-cell refinement), the initial optimisation found for this data consisted of (Cubic P M 3 M with a=b=c=3.77):
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Optimising the first pattern in the seriesThis has probably been done already but optimise the first dataset in your file sequence by slowing releasing parameters; and get the best fit possible. (don't forget to press the Finish Icon so that the newly refined parameters are updated). For information on setting up the first file, refer to Setting up Rietica for doing Le Bail whole profile unit cell refinement
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The Rietbasic ScriptCreate a Rietbasic script to provide the automatic control (a PDF file is provided with the Rietica distribution giving the list of Rietbasic options). As Rietbasic is as a pseudo-programming language, it can be easier just to reverse-engineer and modify an existing Rietbasic script. Thus, modify the following Rietbasic macro script to match the name and number of your data files (the script it is included in the zip file). You would change the following within the script: filestem = 'dat_' startnum = 10 endnum = 20 The example data provided performs mass Le Bail fitting to get unit-cell constants. If you were doing normal structure refinement, get rid of the following line (which copies over the HKL file with the Le Bail intensities: CopyFile(filestem+filenumber+'.hkl',filestem+filenumberx+'.hkl') One limitation with this present script is there is no plotting of the data. You should thus note how the fit parameter is varying and also look at the Rietveld plots after to visually make sure everything has gone as intended. Put the rietbasic RIB file you edited in the same directory where your data exists.
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Using Rietbasic in RieticaRun Rietica and select, Rietveld, Rietveld Basic to bring up the following Rietbasic screen.
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To load the Rietbasic script, within the Rietbasic control menu select, File, Open and select the script file (which will then be displayed in the top half of the Rietbasic interface).
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To run the script, select Run (in this case performing Le Bail fitting/unit-cell refinement on 10 datasets - it could as easily far more datasets); after which all your specified data will be analysed - or you may hit a logic bug in the script (if you hit problems, repair the script and try again).
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After you perform the automatic analysisChecking through the output produced in the lower Rietbasic screen. Load the inp files for any datasets that have higher fit values than surrounding files. (also, it can be good to check each Rietveld fit) You can see from the following that one of the datasets has extra impurity peaks.
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