NGYF
NGYF = [integer]
Default: NGYF = set in accordance with PREC, NGY, ENCUT and ENAUG
Description: NGYF sets the number of grid points in the "fine" FFT grid along the second lattice vector.
On this "fine" FFT mesh the localized augmentation charges are represented if ultrasoft pseudopotentials (USPPs) or the PAW method are used. In case USPPs are used, the local potentials (exchange-correlation, Hartree-potential and ionic potentials) are also calculated on this "fine" FFT-mesh.
By default NGYF is set in accordance with the requested "precision" mode PREC, NGY, and the plane wave kinetic energy cutoffs ENCUT and ENAUG:
PREC NGY NGYF Normal 3/2×[math]\displaystyle{ G_{\rm cut} }[/math] 2×NGY Single (VASP.5) 3/2×[math]\displaystyle{ G_{\rm cut} }[/math] NGY Single (VASP.6) 2×[math]\displaystyle{ G_{\rm cut} }[/math] NGY SingleN (VASP.6) 3/2×[math]\displaystyle{ G_{\rm cut} }[/math] NGY Accurate 2×[math]\displaystyle{ G_{\rm cut} }[/math] 2×NGY Low 3/2×[math]\displaystyle{ G_{\rm cut} }[/math] 3×[math]\displaystyle{ G_{\rm aug} }[/math] Medium 3/2×[math]\displaystyle{ G_{\rm cut} }[/math] 4×[math]\displaystyle{ G_{\rm aug} }[/math] High 2×[math]\displaystyle{ G_{\rm cut} }[/math] 16/3×[math]\displaystyle{ G_{\rm aug} }[/math]
where
- [math]\displaystyle{ E_{\rm cut}=\frac{\hbar^2}{2m_e}G_{\rm cut}^2 \qquad E_{\rm aug}=\frac{\hbar^2}{2m_e}G_{\rm aug}^2 }[/math]
with [math]\displaystyle{ E_{\rm cut} }[/math]=ENCUT and [math]\displaystyle{ E_{\rm aug} }[/math]=ENAUG.
Alternatively, NGYF can be set to a specific value in the INCAR file.