KERNEL TRUNCATION/FACTOR: Difference between revisions

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(Created page with "{{TAGDEF|KERNEL_TRUNCATION/FACTOR| real}} {{DEF|KERNEL_TRUNCATION/FACTOR|$\sqrt{3}$|if {{TAGO|KERNEL_TRUNCATION/IDIMENSIONALITY|0}}|1|if {{TAGO|KERNEL_TRUNCATION/IDIMENSIONALITY|2}}}} '''Description:''' {{TAG|KERNEL_TRUNCATION/FACTOR}} determines the spatial extent of the truncated Coulomb interaction relative to the full cell dimension along the truncation direction{{cite|vijay:arxiv:2024}}. ---- This tag defines the cutoff distance of the Coulomb kernel truncati...")
 
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This tag defines the cutoff distance of the Coulomb kernel truncation boundary. It is expressed as a fraction of the simulation cell length along the truncated axis (e.g., the surface normal for 2D systems).   
This tag defines the cutoff distance of the Coulomb kernel truncation boundary. It is expressed as a fraction of the simulation cell length along the truncated axis (e.g., the surface normal for 2D systems).   
For example, when truncating along <code>z</code>, setting {{TAG|KERNEL_TRUNCATION/FACTOR}} = 0.5 ensures that electrostatic interactions only occur up to half the cell length in the <code>z</code>-direction, effectively centering the truncated region around the middle of the slab or molecule.
{{NB|mind|{{TAG|KERNEL_TRUNCATION/LTRUNCATE}} must be set to <code>.TRUE.</code> for {{TAG|KERNEL_TRUNCATION/FACTOR}} to take effect.}}
{{NB|mind|{{TAG|KERNEL_TRUNCATION/LTRUNCATE}} must be set to <code>.TRUE.</code> for {{TAG|KERNEL_TRUNCATION/FACTOR}} to take effect.}}



Revision as of 07:57, 14 October 2025

KERNEL_TRUNCATION/FACTOR = real 

Default: KERNEL_TRUNCATION/FACTOR = $\sqrt{3}$ if KERNEL_TRUNCATION/IDIMENSIONALITY = 0
= 1 if KERNEL_TRUNCATION/IDIMENSIONALITY = 2

Description: KERNEL_TRUNCATION/FACTOR determines the spatial extent of the truncated Coulomb interaction relative to the full cell dimension along the truncation direction[1].


This tag defines the cutoff distance of the Coulomb kernel truncation boundary. It is expressed as a fraction of the simulation cell length along the truncated axis (e.g., the surface normal for 2D systems).

Mind: KERNEL_TRUNCATION/LTRUNCATE must be set to .TRUE. for KERNEL_TRUNCATION/FACTOR to take effect.

Example

KERNEL_TRUNCATION {
     LTRUNCATE       = T
     IDIMENSIONALITY = 2
     FACTOR          = 0.5
}

This corresponds to truncation along the surface normal (z-direction), keeping interactions within half of the cell length in z.

Related tags and articles

KERNEL_TRUNCATION/LTRUNCATE, KERNEL_TRUNCATION/IDIMENSIONALITY, KERNEL_TRUNCATION/LCOARSEN, KERNEL_TRUNCATION/IPAD, KERNEL_TRUNCATION/ISURFACE

References