NGX: Difference between revisions

Revision as of 12:35, 12 February 2011

NGX = [integer]
Default: NGX = set in accordance with PREC and ENCUT

Description: NGX sets the number of grid points in the FFT-grid along the first lattice vector.

By default NGX is set in accordance with the requested "precision"-mode (PREC) and the plane wave kinetic energy cutoff ENCUT:

where

E_{\rm cut}=\frac{\hbar^2}{2m_e}G_{\rm cut}^2

with E_cut=ENCUT.

Alternatively NGX may be set to a specific value in the INCAR file.

@@ Line 3: / Line 3: @@
 Description: {{TAG|NGX}} sets the number of grid points in the FFT-grid along the first lattice vector.
 ----
-By default {{TAG|NGX}} is set in accordance with the requested "precision"-mode ({{TAG|PREC}}) and the plane wave kinetic energy cutoff {{TAG|ENCUT}}.
+By default {{TAG|NGX}} is set in accordance with the requested "precision"-mode ({{TAG|PREC}}) and the plane wave kinetic energy cutoff {{TAG|ENCUT}}:
+::{| cellpadding="5" cellspacing="0" border="1"
+|{{TAG|PREC}} || {{TAG|NGX}}
+|-
+| Normal || 3/2&times;G<sub>cut</sub>
+|-
+| Single || 3/2&times;G<sub>cut</sub>
+|-
+| Accurate || 2&times;G<sub>cut</sub>
+|-
+| Low || 3/2&times;G<sub>cut</sub>
+|-
+| Medium || 3/2&times;G<sub>cut</sub>
+|-
+| High ||  2&times;G<sub>cut</sub>
+|}
+where
+:<math>E_{\rm cut}=\frac{\hbar^2}{2m_e}G_{\rm cut}^2</math>
+with E<sub>cut</sub>={{TAG|ENCUT}}.
 Alternatively {{TAG|NGX}} may be set to a specific value in the {{FILE|INCAR}} file.