Hi Ruwn, Using a different S02 for each path effectively means that you're using a different coordination number for each path. In some cases, that may be appropriate--for example, small nanoparticles with unknown morphology. It should be noted, however, that S02 often correlates highly with sigma2, and a fit that prefers different S02's may be getting "mixed up" with sigma2's...although in a case like that Artemis/Ifeffit will give high uncertainties to the S02's it finds. More fundamentally, just because a fit matches the data well, it doesn't mean it's "good." The choice of parameters to fit must also be physically justifiable. If you can justify each path having a different coordination number than in your model, you can try different S02's; otherwise, your fit is unconvincing. --Scott Calvin Sarah Lawrence College At 02:31 AM 2/15/2007, you wrote:
Dear Bruce
We have used Athena and Artemis software to analyses the EXAFS. When we do the analysis, we used different S2o for each path for fitting of Cu2O data. I succeeded to obtain good fitting by this way. Documents related to percent EXAFS analysis have been mentioned S2o is one value for all paths. What I want to know is our fittings are correct or not. I am looking forward early response.
About 10 years ago we had being using another program made by Tokyo University in Japan. In this program, the refined parameters also included S2oj and Nj to the each cells
Thanks
Ruwn _______________________________________________ Ifeffit mailing list Ifeffit@millenia.cars.aps.anl.gov http://millenia.cars.aps.anl.gov/mailman/listinfo/ifeffit