[Ifeffit] orbital configuration (FEFF8)

[joshua jason kas]

Hi Iraida,
I believe there are a few issues here that could be addressed/explained.
First, the electronic configuration given at the end of the potentials is 
only the configuration of the valence electrons. For example the 
absorbing oxygen should be interpreted as
      0     0    1.953     ~2s2
      0     1    5.159     ~2p5 (The ~1 extra valence electron for the
 				absorbing atom is due to the attractive
 				core hole)
      0     2    0.040
      0     3    0.000

while for Cd
      1     0    0.723     ~5s1
      1     1    0.711     ~5p1
      1     2   10.149     ~4d10
      1     3    0.000

Here, the differences from the atomic configuration of 4d10 5s2 are due to 
the fact that this is a self-consistent solid state configuration, i.e. 
the valence electrons were allowed to relax and were effected by the solid 
state potential.
That being said, there are ways to change the initial configuration for 
the elements, but you would have to change the source code and recompile. 
I don't think this is what you want to do though. As for improving your 
results, there may be a variety of things that you can do. Off hand your 
input file looks pretty good. One thing you might try is using the card
UNFREEZEF which allows the d electrons from the Cd to tranfer to f states 
which can sometimes be important when the d band is full.
I hope that my answer helps some, at least in interpreting FEFFs output.
Josh Kas
> Hi everyone,I
> would like to calculate K-edge of oxygen XANES spectrum for CdO film. I
> attached my feff.inp file to this e-mail. When I check log1.dat file I
> observe next information:
> "...
> Electronic configuration
>   iph    il      N_el
>     0     0    1.953         //comment: 0-centr.atom (O)
>     0     1    5.159
>     0     2    0.040
>     0     3    0.000
>     1     0    0.723         //comment: 1-Cd
>     1     1    0.711
>     1     2   10.149
>     1     3    0.000
>     2     0    1.921         //comment: 2-O
>     2     1    4.443
>     2     2    0.052
>     2     3    0.000
> mu_new=    -5.168
> Charge transfer:  iph  charge(iph)
>       0   -0.152
>       1    0.417
>       2   -0.417
> Done with module 1: potentials."
>
> As
> is well known, orbital configuration for Cd and O is: 4d10 5s2 and 1s2
> 2s2 2p4, respectively. I think that obtained results for Cd differ much
> according to presented orbital configuration (s,p). So, my question is:
> do there exist some possibilities to change something in my feff.inp
> file to improve the results?
>
> Best regards,
> Iraida.
>
>
>
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