[Ifeffit] Analysis of EXAFS data of a Zn sample with the theoretical model of a similar Mn sample

[Matt Newville]

Abhijeet,


On Wed, Mar 12, 2014 at 8:52 AM, Abhijeet Gaur <abhijeetgaur9 at gmail.com> wrote:
> Hi all,
>             I am trying to analyse the EXAFS data of Zn sample whose
> structure is not available.
>             The crystallographic data is available for a Mn sample which is
> likely to have same coordination environment as Zn sample .
>             Is it possible to use the theoretical model generated for Mn
> sample for the EXAFS analysis of the Zn sample?
>             How much error is expected in the structural parameters obtained
> from such fittings?
>
> With thanks in advance
>
> --
> Dr. Abhijeet Gaur

You should be able to start with the crystal structure of th Mn
compound, run Atoms to generate a feff.inp.  Then edit that feff.inp
file to make the absorbing atom (IPOT 0) Zn instead of Mn, that is
simply changing

    POTENTIALS
      * ipot   Z      tag
         0     25    Mn

to
    POTENTIALS
      * ipot   Z      tag
         0     30    Zn

It's possible that you would want to replace some of the Mn scatters
by Zn as well, but that depends on the details of the structure and
what you are trying to model.

You may see a significant refinement in Zn-O distance compared to the
Mn-O from that crystal structure.  Again, this would depend on the
details of the structure.

--Matt