Mauro, Your problem is a genuine bug. When I go through the contents of the cell to determine how many ipots to assign, the Fe atom gets noticed and added to the list of species in the cell. I should exclude the absorber from consideration at that step. I don't see immediately how to fix that problem, but I'll try to come up with a solution and check it into svn soon. I can suggest a work-around. It still requires editing the feff.inp file generated, but it is a much less onerous editing chore: * In the atoms.inp file, change the iron atom to Ga and give it a tag -- something like this: Ga 0.444444444444444 0.555555555555555 0.3455528537 Abs * Change the value of the "core" keyword to the tag: core = Abs * Run feff, and edit the first element of the potentials list. That is still annoying, but much less so than the feff.inp file you attached to your email. B On Friday 19 September 2008 10:40:04 Mauro Rovezzi wrote:
Dear all,
I would like to submit to your attention a problem with Atoms that I still do not understand. What I would like to do is to generate a FEFF input file starting from a supercell, that is repeating the unit cell NXxNYxNZ times and create the crystal with the resulting box.
An example is given in the attached _test-atoms.inp_ created following this procedure: from wurtzite GaN (a,c cell parameters) that we describe with 2 atoms I reduce the symmetry and I use 4 atoms, then I create a 72 atoms supercell - 4*(3x3x2) - that has 3ax3ax2c dimensions and finally I tell atoms to use "P1" space group in order to replicate the supercell in x,y,z space and shift at the center the absorbing atom.
Here the *problem*: the resulting _test-feff8.inp_ present good values of distances but strangely it has generated an additional Fe potential (there is just 1 Fe absorbing atom in the box/list). This is annoying because I have to remove manually the wrong "ipot" to run FEFF.
Is it a stupid mistake generating the Atoms input file or is it an odd behaviour?
Cheers, Mauro
PS: Atoms 3.0.1 (linux) 05/08/15 PPS: Do not pay attention to coordinates and distances, these are just test-files!
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