HI Matt,
That cif file is an old version of the structure. I can get DArtemis to crash if I use it too, but if I
shift the origin by -1/8, -1/8, -1/8 it works. No crash when running Feff.
Some more recent references for the structure:
http://rruff.geo.arizona.edu/AMS/minerals/Hercynite Fd-3m has two origin choices.
When you look at the Feff atoms list (in feff.inp or in the DArtemis Feff window/tab),
the difference between the two calculations (your attached cif versus space group origin shift/other
structure determination) is quite apparent.
As per cif:
ATOMS * this list contains 257 atoms
* x y z ipot tag distance
0.00000 0.00000 0.00000 0 Fe1 0.00000
2.03000 2.03000 0.00000 2 Fe1.1 2.87085
-2.03000 -2.03000 0.00000 2 Fe1.1 2.87085
-2.03000 0.00000 2.03000 2 Fe1.1 2.87085
0.00000 -2.03000 2.03000 2 Fe1.1 2.87085
2.03000 0.00000 -2.03000 2 Fe1.1 2.87085
0.00000 2.03000 -2.03000 2 Fe1.1 2.87085
etc...
With origin shift:
ATOMS * this list contains 245 atoms
* x y z ipot tag distance
0.00000 0.00000 0.00000 0 Fe1 0.00000
-1.05560 1.05560 1.05560 3 O1.1 1.82835
1.05560 -1.05560 1.05560 3 O1.1 1.82835
1.05560 1.05560 -1.05560 3 O1.1 1.82835
-1.05560 -1.05560 -1.05560 3 O1.1 1.82835
etc.
regards,