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Dear FEFF users, I have a few, probably, basic questions concerning XANES
calculations using FEFF 8.20, which I haven’t found in FEFF manual: 1) I was wondering whether it is possible to change the
oxidation state of the absorber in FEFF input file (is there any card that
could be helpful doing so)? 2) Furthermore I would like to ask how does FEFF code know
about bound-to-bound transition and resonances close to the ionization potential? 3) How are the intensities of below and above ionization
potential resonances scaled (i.e. how are the intensities interpolated)? 4) How does the code estimate the ionization potential
values? Does it starts taking it atomic value and then corrects it during the
calculation of potentials of a given cluster? So, if one wants to change the
ionization potential value explicitly (i.e. taking into account the edge shift
during the oxidation state change of the absorber) how can it be done in FEFF
code? Could one calculate a free atom spectrum? 5) How can one take into account charge transfers in FEFF?
Meaning, changing the number of electrons on a given atom (in my case it would
be the Ru atom which loses one electron upon excitation and this is detected by
observing approx. 1.2 eV shift of the edge toward higher energies) ? I hope there is someone who can help me out and clarify my
doubts and lack of experience with this code. I’ll greatly appreciate any
help and suggestions. Cheers, Wojciech Gawelda ********************************************************************* Wojciech Gawelda Laboratoire de
Spectroscopie Ultrarapide (LSU) Institut des Sciences et
Ingénierie Chimiques (ISIC), Faculté des Sciences de Base
(SB-BSP) Ecole Polytechnique Fédérale
de Lausanne (EPFL) CH-1015
Lausanne-Dorigny, Switzerland Tel.: +41 (21) 693 0452 Fax.: +41 (21) 693 0422 E-mail: wojciech.gawelda@epfl.ch WWW: http://lsu.epfl.ch ********************************************************************* |