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KSPACING-tag and KGAMMA-tag

KSPACING = [real]
KGAMMA = [logical]

Default:    
KSPACING = 0.5
KGAMMA = .TRUE.


The tag KSPACING determines the number of k-points if the KPOINTS file is not present (see Sec. 5.5). KSPACING is the smallest allowed spacing between k-points in units of Å$ ^{-1}$. The number of k-points increases when the spacing is decreased. The number of k-points in the direction of the first, second and third reciprocal lattice vector is determined by the equations

$\displaystyle {\rm max}(1, \vert {\vec b}(i)\vert / {\tt KSPACING} )
$

These values are rounded to the next integer. The generated grid is either centred at the $ \Gamma $ point (e.g. includes the $ \Gamma $ point) (KGAMMA=.TRUE.) or is shifted away from the $ \Gamma $ point, as usually done for Monkhorst Pack grids (KGAMMA=.FALSE.) (compare Sec. 5.5.3). Per default, the grids include the $ \Gamma $ point.



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