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NKREDX = [integer]
Default: NKREDX = 1
Description: NKREDX specifies a reduction factor for the q-point grid representation of the exact exchange potential along reciprocal space direction b1.
where b1,2,3 are the reciprocal lattice vectors of the primitive cell, and Ci is the integer grid reduction factor along reciprocal lattice direction bi. This leads to a reduction in the computational workload by a factor:
In case one sets NKRED, the grid reduction factors will be uniformly set to C1=C2=C3=NKRED. If one wants to specify separate grid reduction factors for C1, C2, and C3 one should use C1=NKREDX, C2=NKREDY, and C3=NKREDZ, respectively.