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jedit examples

Some examples that should get you started with creating input files from scratch in jedit are given below. To run them easily you need to install the topas_durham macros. If you don't already have these save the file linked here in your jedit .xinsert directory (normally c:\documents and settings\username\.jedit\xinsert). Then quit and restart jedit. These macros just contain the subset of topas instructions that you'll need for these simple examples. These are meant as quick demonstrations only - not "text book" examples of how to do a Rietveld refinement! More detailed tutorials are available via the link on the menu on the left.

1. A simple lab Rietveld refinement.

Save the following files in a directory which are for an lab X-ray data collection on TiO2:

d5_05005.raw; rutile.cif

Launch jedit. Click on the "new inp" button and browse to find the d5_05005.raw file. This creates a new input file d5_05005.inp which can be used to run topas. You need to enter sufficient information in this file for topas to perform a Rietveld refinement. Put the cursor above the "xdd d5_05005" line and click on the "file header" node. Click on the line below the "xdd d5_05005". You can then click on each of the nodes in turn. In this case the data were recorded on the durham d5000 with fixed slits and it is appropriate to refine a height correction. As you have a cif file for the material it can be read in directly. In cases where you don't have a .cif file you'd click through the items in the "Structure - no cif" folder. If you'd like to see the structure click on "view_structure". Then save the file and run it in topas. This can be done by clicking the "Save and send to topas" button and the "run topas" button then switching to topas and pressing the run arrow. Alternatively you should be able to do this by clicking on the two icons below which should appear in your jedit menu bar:

run topas academic:

save file and send to topas academic:

Refine temperature factors by adding the phrase "beq @ 0" at the end of each site line. N.B. you can do this quickly in jedit by column highlighting the end of each line then typing....the text you type will appear on each line simultaneously. Then try giving the O1 x and y coordinates the same parameter name and refining them. i.e. change the line to read:

site O1 x xo1 0.30600 y xo1 0.30600 z 0.00000 occ O 1.00000 beq @ 0.1064`

 

2. A Simple Time of Flight Refinement

Save the following files in a directory:

zx0002.xye; zrw2o8_300k.cif

The xye file is a time of flight data set recorded on HRPD at the isis pulsed neutron source. If you click through the various headings under "Simple tof Rietveld" you should be able to perform a simple Rietveld fit to the data.

3. A Simple Pawley Refinement

Save the following file in a directory:

d5_00450.raw

The data were recorded on the Durham d5000 using variable slits on a sample of Y2O3. The cell parameter is around 10.6 Angstroms and space group is Ia-3. By clicking through the headings under the "Lab Pawley Refinement" folder you should be able to fit the data and get an R-factor around 4.5% without changing any of the refinement settings.


Modified 07-Oct-2004 by John S.O. Evans. Pages checked for Netscape 7 and Internet Explorer 5.5.