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LNMR SYM RED
LNMR_SYM_RED = .TRUE. | .FALSE.
Default: LNMR_SYM_RED = .FALSE.
Description: discard symmetry operations that are not consistent with the way k-space derivative are calculated in the linear response calculations of chemical shifts.
The star on which the k-space derivative is calculated is oriented along the cartesian directions in k-space. If the symmetry operations in k-space do not map this star onto itself, erroneous results can be obtained. To have VASP check for such operations, set LNMR_SYM_RED=.TRUE., and such operations will be discarded, resulting in a larger IBZ. In case of any doubt set LNMR_SYM_RED=.TRUE. Beware: It matters how the real space lattice vectors are set up relative to the cartesian coordinates in POSCAR. It determines the orientation of the k-space star and hence can affect the efficiency via the number of k-points in the IBZ.