[Ifeffit] how to consider Jahn-Teller distortion?

[Matt Newville]

Hi Matthew, Enyuan,

You're absolutely right that the JT distortion is better described as
moving the ligand atoms.   I was too focused on "edit feff.inp to move
the atoms" and on trying to wrap my mind around R -3 m to do the
correct distortion.   Enyuan, you'll want to edit the atomic list with
a better approximation of the the expected distortion.   I do think it
would be challenging to separate any reasonable distortion from an
increase in sigma^2, especially with data only to 12.5Ang^-1.

--Matt