Download FDMNES User's Guide

FDMNES User’s Guide
Then one gets a series of output files with the extensions _sph_signal_xan.txt,
_sph_signal_pol1.txt, _sph_signal_rxs1.txt for the contributions on each polarization and
reflections. The number after pol or rxs is the number of the polarization or reflection.
III-18) Calculation area boundary
By default in FDM, the meshing is performed in a sphere extending up to the last atom
inside the sphere of radius given under "radius" plus the atomic radius (by default 0.65 A)
plus one interpoint distance (0.2 A by default). In order to use a bigger sphere put
Overad
1.2
distance over the last atom + its radius to take into account.
III-19) Displacement of the absorbing atom
To move the absorbing atom in reference to its position given under "molecule" or
"crystal" put:
dpos
0.2 0.0 0.0
displacement vector in Angström
III-20) Getting back the tensor components from a previous calculation
It is possible to get back the tensor component from a previous calculation ( is in the
fdmnes_out_bav.txt type file) and to compute other polarizations putting the key word extract
followed by the corresponding name:
Extract
c:\users\joly\xanout\calcul_prec_bav.txt
In case of calculations for different absorber position whose number is the number of output
files, one has to extract the tensors from these n files if there are n non equivalent absorbing
atoms. The use of the keyword "absorbeur" is then absolutely necessary. The list of the files
under "extract" must correspond in number and in order to the list of atoms under
"absorbeur":
Extract
c:\users\joly\xanout\calcul_prec_1_bav.txt
c:\users\joly\xanout\calcul_prec_2_bav.txt
Absorbeur
1 2
It is possible to make rotations of the local repair. It can be useful when using tensor
calculated in a different base. It is possible de make 1, 2 or 3 rotations around the axes 0z,
then Ox, then Oy. Each rotation defines a new local base, starting point of the next rotation.
For this write:
-31-