[Wien] txspec

[Peter Blaha]

> I am talking about the SO splitting of core level, not about the SO splitting of valence states. Pt 2p-level, for example, splits into 2p_1/2 and 2p_3/2 due to the SO coupling and the transitions from 2p_1/2 level to empty states above the Fermi level corresponds to the L2-edge spectrum and the transitions from 2p_3/2 level to the L3-edge spectrum. Therefore, for Pt the L2- and L3-edges are split
> by about 1730 eV.

In pure dipole approximation !! the L2 and L3 spectra are "identical" in
shape (neglecting the slightly different form of the 2p1/2 and 3/2 wf and
thus slightly modified matrixelements) and only "splitted" in energy (in
Pt aparaently by 1730 eV). This SPLIT can be mimicked by the SPLIT
parameter of TXSPEC, but since the split is so large (your spectra are
probably only 10-20 eV wide) it makes no sense to include this directly.
As I said, it is usefull only, when the core states are split only by a
few eVs and the L2 and L3 spectra thus overlap.

>  for the Pt 2p level the angular momentum quantum number is already fixed
>  (l=1), there are only two possible transitions: to l=2 (d-states) and
>  to l=0 (s-states). I think that the program 'txspec' can split these
>  two transitions, but not for the L2- and L3-edges. And I do not think
>  'SPLIT' can differentiate the L2- and L3-edges, either. I think the
>  parameter 'SPLIT' can do distinguish the l -> l+1 tanstion and l -> l-1
>  transition only. So, if the program 'txspec' uses only 'l' qunatum
>  number without differentiating the L2- and L3-edges, the resultant
>  spectrum is the sum of L2- and L3-edge spectra. Am I correct?

The resulting spectrum is calculated only for one type (I'm at the
moment not sure which core state is actually used, probably p3/2)
since these two spectra are the "same" (see above)) and are well seperated
in energy.

Of course the spectra are the sum of the l+1 and l-1 transitions (and you
can plot both contributions individually), but this has NOTHING to do with
the SPLIT parameter.

Regards
                                      P.Blaha
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Peter BLAHA, Inst.f. Materials Chemistry, TU Vienna, A-1060 Vienna
Phone: +43-1-58801-15671             FAX: +43-1-58801-15698
Email: blaha at theochem.tuwien.ac.at    WWW: http://info.tuwien.ac.at/theochem/
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