[Wien] Questions regarding xspec and optic

[prasenjit roy]

Dear WIEN2k users and Prof. Blaha,


                 I am using WIEN11.1 version. While doing the XANES and
XMCD calculations I faced few problems, which I have arranged below. I
searched the mailing list, and also the
Exercise11.pdf<http://www.wien2k.at/reg_user/textbooks/WIEN2k_lecture-notes_2011/Exercises_11.pdf>but
did not find the appropriate solution. My System is Fe2P, S.grp -
189. Metallic. Unitcell contains 6 Fe (Fe1: 3g, Fe2: 3f site) and 3 P(P1:
2c, P2:1b).

              1. For XANES: If my structure file contains atoms with
multicplicity > 1 (in my case, 3), then after making the supercell (1x1x2),
if I remove one 1s electron from Fe1, it actually creating 3 core-holes
instead of 1 (inside the supercell). So How should I create the case.struct
file at the first place?

              2. For obtaining XANES without core-hole, { and also with
core-hole } do I need to create k-points over the whole BZ ( in chapter
8.16 of UG (pp 156), it is written that for X-ray ABS spectra, eigenvalue
must be calculated over whole BZ )?

              3. Is the Energy window in case.inxs depends on EMAX, NBANDS
in case.in1c?

              4. For XMCD, I need only K-edge . Even for that should I do
SO calculation? If yes, as far as I understood, the lineup of steps will
look like this after creating the unit-cell,:: a) Init_lapw ; b)
Initso_lapw (or, symmetso -c ?); c) runsp_lapw -so ; d) x kgen -so ; e) put
FERMI in case.in2c ; f) runsp_lapw -so -c -s lapw1 -e lcore ; g) x opticc
-so -up ; h) x joint -up ; i) x kram -up .
                 For more accurate calculation, should I use
core-hole approach for XMCD, as suggested
here<http://www.wien2k.at/reg_user/textbooks/WIEN2k_lecture-notes_2011/Ambrosch-Draxl_optics_bse.pdf>
?

                Thank you very much In Advance.


With Regards,
Prasenjit Roy
Radboud University
Nijmegen
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