## Core spectrum calculations for EELS

In the output section of the Fleur input file it can be specified that a core spectrum has to be calculated. For this output/@coreSpec has to be set to T and in the output section the optional element coreSpectrum has to be defined in analogy to the following example:

<coreSpectrum eKin="300.0" atomType="1" lmax="2" edgeType="L"
eMin="-1.0" eMax="15.0" numPoints="17" nqphi="10"
nqr="10" alpha_Ex="0.024" beta_Ex="0.050"
I_initial="155" verbose="T">
<edgeIndices> 3 </edgeIndices>
</coreSpectrum>

Attribute Description
eKin The kinetic energy of the incoming electron in units of keV. The relativistic correction term, which was shown to be important (see PhD thesis of Kevin Jorissen ), is proportional to eKin.
atomType This is the index of the atom group for which the EELS is to be calculated.
lmax Maximum value of the angular momentum to be considered in the EELS calculation. By setting it to a reasonably low value (e.g. 2 or 3), the calculation is significantly faster in comparison with no lmax restriction.
edgeType The edge selection: K, L, M, ...
eMin The bottom edge of the energy interval with respect to the Fermi energy for which the EELS is calculated.
eMax The top edge of the energy interval with respect to the Fermi energy for which the EELS is calculated.
numPoints Number of points in the [eMin,eMax] interval for which the EELS is calculated..
nqphi Number of angular divisions of the q-mesh, optional, standard value: 10
nqr Number of radial divisions of the q-mesh, optional, standard value: 10
alpha_Ex Experimental convergence semi-angle in rad, optional, standard value: 0.024
beta_Ex Experimental collection semi-angle in rad, optional, standard value: 0.05
I_initial Initial intensity of the incoming electron beam, optional, standard value: 155
verbose Verbose output is produced, optional, standard value: F

In the edgeIndices element a list of space separated indices has to be provided.