Dear Nic, this sounds like your fit is shifted to the experimental chi(k) by half an oscillation period. Typically, you can recognize this by looking at the enot value. So what is your enot value like? Does it help changing the enot starting value by a couple of eV? Finally, (and this is a FAQ item) could you maybe post a sample Artemis project so that we can easily see what has happened? Regards, Dominik On 01.08.2011 06:36, Nicholas.Tse@csiro.au wrote:
Dear All,
Just wondering what could I do to make the amp guess value as a positive number? If I run it and let it float (i.e. guess), the amp becomes negative in the resulting fits, but the fit has nice delr and ss values (i.e. make sense). If I restrict the amp value to 1, everything else doesn’t fit. I am only fitting the first nearest neighbour in a measured standard; Gadolinium oxide.
Regards,
Nic
**
*Nicholas Tse* Postgraduate Student, University of Melbourne CSIRO Materials Science and Engineering.
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