Hi Hashem, Atoms doesn't handle the occupancy data in the CIF file. See this page for more info: <a href="http://cars9.uchicago.edu/iffwiki/FAQ/FeffitModeling#head-b273ecfd19542ec82ea031bbcc57ff8861fc11f9">http://cars9.uchicago.edu/iffwiki/FAQ/FeffitModeling#head-b273ecfd19542ec82ea031bbcc57ff8861fc11f9</a> I assume you see a message like this one that I see:     This warning indicates a problem in the Atoms list.  For some     reason you have atoms that are separated by than 0.93 Angstroms     (or 1.75 Rydberg). If you look on the Atoms tab in Artemis when you open the CIF file, you should see that the co-ordinates for Mg and Al are all 0.00000 ; i.e., all Atoms sees is that they are in the same place. Bruce, here's two bug reports: 1. The warning message above is missing the word "less", as in "separated by _less_ than 0.93 Angstroms" 2. It's an extensive message but doesn't mention this kind of problem. If you want to drive yourself mad with interface stuff, you could catch and highlight these errors on input and disable the controls they affect until the input is corrected. A tricky part of that is making sure the user knows what the highlighting means and has a clue about how to fix the error without - say - throwing up a talking paperclip. A sort of "heavy tooltip" ("lead balloon"?) could be shown - placed so as not to obscure the relevant controls - with a brief message, a way to get to the more help, and dismissal button. An automatic fade out might be nice, not sure. So long as the bad input exists, there should be a way to get the message back, like mousing over the highlighted input or the disabled controls. I don't know of any cross-platform toolkit that makes that kind of thing easy. Cheers, Greg <div class="gmail_quote">On Thu, Dec 18, 2008 at 10:04 PM, Hashem Stietiya <<a href="mailto:mstiet2@lsu.edu">mstiet2@lsu.edu</a>> wrote: <blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"> <div link="blue" vlink="purple" lang="EN-US"> <div> Hello!   I was using Artemis to run feff and generate paths from hydrotalcite. However, it failed to run and an error message indicated that there is something wrong with the crystallographic data. I used the crystallographic data of hydrotalcite from different sources, but encountered the same problem. Can you please help identify the problem and run feff?   Please find attached the crystallographic data for hydrotalcite.   I appreciate your help.   Regards, Hashem Stietiya Louisiana State University   </div> </div> _______________________________________________ Ifeffit mailing list <a href="mailto:Ifeffit@millenia.cars.aps.anl.gov">Ifeffit@millenia.cars.aps.anl.gov</a> <a href="http://millenia.cars.aps.anl.gov/mailman/listinfo/ifeffit" target="_blank">http://millenia.cars.aps.anl.gov/mailman/listinfo/ifeffit</a> </blockquote></div>