[Ifeffit] Too Many Atoms

[Bruce Ravel]

On Thursday 30 June 2005 19:23, rvv052 at mail.usask.ca wrote:
> The problem that I have is that with 141 crystallographic sites for a DNA
> molecule and a space group  p 4 2 2, I end up with 611 atoms after running
> ATOMS. This gives me the error: Feff 6L.02 Fatal Error: Too many atoms in
> ATOMS list. Maximum is   500. I tries decreasing the number of
> crystalographic sites by removing hydrogen atoms, but then I got another
> error: Feff 6L.02 No atoms or overlap cards for unique pot 1 Cannot
> calculate potentials, etc. Fatal Error: at RDINP. I tried increasing the
> Rmax as indicated, but this only served to increase the number of atomes,
> leading me to the error given above. I was hoping that someone could help
> me with this problem.

The easiest solution is to run atoms and have it generate the list of 611
atoms.  At some point prior to the 500th atoms, insert a line that says END
and nothing else.  That will tell Feff to stop reading at that line and
thus should avoid the "Too many atoms in ATOMS list" problem.

Removing the hydrogens is not a great solution, as explained here:
  http://millenia.cars.aps.anl.gov/pipermail/ifeffit/2005-April/001724.html
although the source of your error is probably that you removed the hydrogens
from the Atoms list, but did not remove hydrogen from the potentials list.

B

-- 
 Bruce Ravel  ----------------------------------- bravel at anl.gov  -or-
						  ravel at phys.washington.edu
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