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 derivatives 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 check for such operations, set LNMR_SYM_RED=.TRUE.. VASP then disregards such operations and the resulting first Brillouin zone (IBZ) is larger. In case of any doubt set LNMR_SYM_RED=.TRUE.

Warning: It matters how the real-space-lattice vectors are set up relative to the cartesian coordinates in the POSCAR file.

It determines the orientation of the k-space star and, hence, can affect the efficiency via the number of k-points in the IBZ.

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