[Ifeffit] boundary issue in artemis

Scott Calvin dr.scott.calvin at gmail.com
Tue Jan 17 05:51:39 CST 2017

Hi Marcus,

>From the graph, it looks likely that one of your sigma2’s is negative, causing the fit to blow up at high k. 

If so, then the apparently good fit below k=9 is actually a “false fit,” meaning that it looks good on a graph, but is nonphysical. Unfortunately, that means you have more work to do in adjusting the model; you shouldn't just narrow the fitting window and ignore the misfit.

Scott Calvin
Lehman College of the City University of New York

> On Jan 17, 2017, at 4:21 AM, mfehse <marcus.fehse at univ-montp2.fr> wrote:
> Dear all,
> im fitting Ti next neighbour environment and I'm facing the problem that above a k value of 9 the fit deviates completely and does not follow the data any more. I dont really understand what is happening, so im forced to limit my fitting window in order to avoid this effect.
> i have attached a plot in k space so you can better understand what im talking about.
> any hints would be appreciated<Ti1st_disch_fit.png>_______________________________________________
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