[Ifeffit] Pre-edge reproduction in FEFF8 for Cobalt molecules

[Janine GRATTAGE]

Dear all,

I am studying the K edge XANES of a series of cobalt containing 
molecules and I am having trouble reproducing the pre-edge features 
using FEFF8.4. For all three "acac" molecules I studied (which have 
different acetylacetonate ligand arrangements on the Co atom), the 
experimental pre-edges show two or three features of varying 
intensities, but the FEFF calculated pre-edge is identical for each 
molecule. I have tried for one of the molecules, Co(acac)2, to use both 
the dipole contribution only, and both the dipolar and quadrupole 
components in the calculations, by using the card MULTIPOLE 0 and 
MULTIPOLE 2 - two figures are attached.

For the input file (attached also) the atomic coordinates were 
calculated by using a density functional theory minimised molecular 
geometry using ADF. Any suggestions as to how to improve the pre-edges 
(i.e. show more than one feature, and vary for the different molecules) 
would be welcome!

Thank you in advance,

Dr. Janine Grattage
Postdoc, ESRF.
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