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KPOINT_BSE = [integer] (optionally [integer],[integer],[integer])
Descprition: The flag KPOINT_BSE allows to calculate the dielectric matrix at one of the kpoints used to sample the Brillouin zone.
In the simplest form one can specify
KPOINT_BSE = index_of_k-point
It is best to select the desired k-point from the list of k-points in the OUTCAR file. Additionally a shift by an arbitrary reciprocal lattice vector can be supplied by specifying three additional integer numbers:
KPOINT_BSE = index_of_k-point n1 n2 n3
This allows the calculate the dielectric function at a k-point outside the first Brillouin zone corresponding to
where are the reciprocal lattice vectors of the unit cell.