[Ifeffit] linear combination fitting and Artemis?

[Matt Newville]

Hi Winejar,


On Sat, Mar 10, 2012 at 9:05 AM, winejar8324 <winejar8324 at gmail.com> wrote:
> Hello, everyone
>
> Here I got the spectra of components in a mixture with linear combination
> fitting.
>
> Can i fit directly the component spectra (i.e. chi(k) of specific species)
> using Artemis to get the structure information of the specific component?

Yes.  It may not be easy to do, as the chi(k) spectra is, well, a
linear combination of two distinct chi(k) from two distinct phases.

In general, that would require modeling the two components with
different Feff calculations, combining the paths from those into two
separate chi(k), and adding these together, weighted by the fraction
of each phase.   It *can* be done, and has been done many times, but
it may not be easy in all cases.

> I saw the manual (linear combination fitting) says that "The data group
> containing the fit result will be treated as normal data that can have a
> background removed or be Fourier transformed. When you save a fit using
> the derivative spectra, the fit group will be saved as a normal mu(E)
>  spectrum".
>
> Does it mean that i can fit directly the data mentioned above?

Yes.  You can analyze the individual extracted components.

--Matt