[Ifeffit] Amplitude in Artemis

[Paul]

Pre and post edges are fine, and the model I'm using is made from the 
crystallographic data collected. I wouldn't have thought getting a decent 
fit with good data is difficult with the crystal structure as the model.

But I'm assuming there is not any kind of reason amp can be above 1. Problem 
is, if I restrain it to be between 0 and 1 it sits at 1 with an error of +/- 
40.

----- Original Message ----- 
From: "Scott Calvin" <SCalvin at slc.edu>
To: "XAFS Analysis using Ifeffit" <ifeffit at millenia.cars.aps.anl.gov>
Sent: Monday, February 27, 2006 11:19 AM
Subject: Re: [Ifeffit] Amplitude in Artemis


> Hi Paul,
>
> The most likely possibilities are:
>
> 1) The normalization (in Athena or whatever) is way off. Make sure you 
> check it by eye and see that the pre-edge or post-edge line isn't crazy 
> for some reason.
>
> 2) The model isn't right...your samples are not what you think they are.
>
> So no, I don't think you have a legitimate fit at this point.
>
> --Scott Calvin
> Sarah Lawrence College
>
> At 08:11 PM 2/26/2006, you wrote:
>>Uncertainty can get fairly close to 0 (+/- 0.1)  but amp gets up anywhere 
>>from 2 to 4 depending on what data set I'm fitting to.
>
>
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