KERNEL TRUNCATION/LTRUNCATE: Difference between revisions

Revision as of 09:31, 17 March 2026

KERNEL_TRUNCATION/LTRUNCATE = .True. | .False.
Default: KERNEL_TRUNCATION/LTRUNCATE = .False.

Description: Truncates the Coulomb kernel to remove electrostatic interactions along non-periodic dimensions.

Setting KERNEL_TRUNCATION/LTRUNCATE = T switches on the Coulomb-kernel-truncation method. It removes interactions with periodic replicas in non-periodic directions. In other words, the interactions are removed along the surface normal for 2D materials, and along all directions for 0D systems, i.e. for isolated atoms and molecules.

Important: Slabs must be centered in the unit cell.

Mind:

KERNEL_TRUNCATION/LTRUNCATE acts as a "super-tag", i.e. unless this tag is switched on further options in KERNEL_TRUNCATION will be ignored.
This tag is only available as of VASP.6.5.0.

Default settings

The following default settings are assumed when setting KERNEL_TRUNCATION/LTRUNCATE = T,

  KERNEL_TRUNCATION/LTRUNCATE = T
  KERNEL_TRUNCATION/IDIMENSIONALITY = 0
  KERNEL_TRUNCATION/LCOARSEN = T

which translates to 0D coulomb truncation. This is suitable for a molecule using the coarsen before pad strategy^[1]. The above INCAR settings can equivalently be specified using the following nested syntax

  KERNEL_TRUNCATION {
        LTRUNCATE      = T
        IDIMENSIONALITY = 0
        LCOARSEN       = T
  }

Detailed information about the setting are documented on respective related tags.

References

↑ S. Vijay, M. Schlipf, H. Miranda, F. Karsai, M. Kaltak, M. Marsman, and G. Kresse, Efficient periodic density functional theory calculations of charged molecules and surfaces using Coulomb kernel truncation, Phys. Rev. B 112, 045409 (2025).

[vijay:prb:2025-1] S. Vijay, M. Schlipf, H. Miranda, F. Karsai, M. Kaltak, M. Marsman, and G. Kresse, Efficient periodic density functional theory calculations of charged molecules and surfaces using Coulomb kernel truncation, Phys. Rev. B 112, 045409 (2025).

[1]

@@ Line 1: / Line 1: @@
 {{TAGDEF|KERNEL_TRUNCATION/LTRUNCATE| .True. {{!}} .False.|.False.}}
+{{DISPLAYTITLE:KERNEL_TRUNCATION/LTRUNCATE}}
-Description: {{TAG|KERNEL_TRUNCATION/LTRUNCATE}} truncates the coulomb kernel to remove electrostatic interactions along non-periodic dimensions
+Description: Truncates the Coulomb kernel to remove [[:Category:electrostatics|electrostatic interactions]] along non-periodic dimensions.
 ----
-Setting {{TAG|KERNEL_TRUNCATION/LTRUNCATE}} = T  switches on coulomb kernel truncation methods. These methods removes interactions with periodic replicas in non-periodic directions, i.e. along the surface normal for 2D materials and along all directions for 0D systems such as atoms and molecules.
+Setting {{TAG|KERNEL_TRUNCATION/LTRUNCATE}} = T  switches on the Coulomb-kernel-truncation method. It removes interactions with periodic replicas in non-periodic directions. In other words, the interactions are removed along the surface normal for [[2D materials]], and along all directions for 0D systems, i.e. for isolated atoms and molecules.
+{{NB|important| Slabs must be centered in the unit cell.}}
 {{NB|mind|
-*This tag acts as a "super-tag", i.e. unless this tag is switched on further options in KERNEL_TRUNCATION will be ignored.
+*{{TAG|KERNEL_TRUNCATION/LTRUNCATE}} acts as a "super-tag", i.e. unless this tag is switched on further options in KERNEL_TRUNCATION will be ignored.
 *This tag is only available as of VASP.6.5.0.}}
@@ Line 11: / Line 13: @@
 The following default settings are assumed when setting {{TAG|KERNEL_TRUNCATION/LTRUNCATE}} = T,
+   {{TAGBL|KERNEL_TRUNCATION/LTRUNCATE}} = T
+   {{TAGBL|KERNEL_TRUNCATION/IDIMENSIONALITY}} = 0
+   {{TAGBL|KERNEL_TRUNCATION/LCOARSEN}} = T
+which translates to 0D coulomb truncation. This is suitable for a molecule using the coarsen before pad strategy{{cite|vijay:prb:2025}}. The above {{FILE|INCAR}} settings can equivalently be specified using the following nested syntax
     KERNEL_TRUNCATION {
@@ Line 18: / Line 26: @@
     }
-which translates to 0D coulomb truncation which is suitable for a molecule using the coarsen before pad strategy{{cite|vijay:prb:2025}}. Detailed information is available on the respective pages of the {{FILE|INCAR}} tags.
+Detailed information about the setting are documented on respective related tags.
 == Related tags and articles ==
@@ Line 29: / Line 37: @@
 ==References==
-[[Category:INCAR tag]][[Category:Electrostatics]]
+[[Category:INCAR tag]][[Category:Electrostatics]][[Category:2D materials]]