Hi, I would like to fit the NiFe2O4 spinel structure to EXAFS data of mixed Ni/Fe-(hydro)xide films. However, ATOMS cannot deal with structures exhibiting crystal sites with partial occupancies. I know that this problem has been adressed to some extent on the mailing-list already in May 2012 (see http://millenia.cars.aps.anl.gov/pipermail/ifeffit/2012-May/010544.html) and Bruce Ravel shortly outlined how to edit the .cif file in order to run ATOMS and FEFF6. Attached you find the NiFe2O4.cif file that I like to employ. I tried the following: 1. changed occupancy from 0.5 to 1 in line Ni1 Ni2+ 16 d 0.625 0.625 0.625 . 0.5 0 2. subsequently deleted line Fe2 Fe3+ 16 d 0.625 0.625 0.625 . 0.5 0 I got rid of the ATOMS warning concerning the partial occupancy but FEFF6 crashes due to atoms being postioned too closely to each other. I am pretty sure that my editing resulted in a change of the structure. I would be very glad if someone could explain to me in some detail how I need to edit the .cif. Thank you very much for your help. Best, Kai