Re: [Ifeffit] too small bond length in R space

That is a difficult problem. You might consider using the structural model as a guide for setting the background r max by comparing the data and model if you are confident that the model is close to the sample you are studying. Good luck. Chris Patridge

On Nov 9, 2014, at 6:54 AM, ZHAN Fei wrote:

Dear all： I encounter a problem of exafs fit in an example of Mo which have Mo-O Mo-S Mo-Mo bond.The problem is that the Mo-O peak in R space has too small bond length (less than 1.4A(+0.5A for phase correction) ).Because when 1.2>rbkg>0.68 there is little change in spectrum of R and k space,and when I increase the value of rmin of forward Fourier transform the peak changes little,so I think it's not a noise.But when I try to fit it use the 1.35A path of Mo-O,I can't fit it well. Could you give me some advise about fit too small bond length,or recommend papers of similar situation? picture of R space is attached. Thanks Sincerely, zhanfei ihep of China <R space.png>

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