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KERNEL_TRUNCATION/LTRUNCATE

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Revision as of 09:31, 17 March 2026 by Huebsch (talk | contribs)

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.

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.

Related tags and articles

KERNEL_TRUNCATION/LCOARSEN, KERNEL_TRUNCATION/IDIMENSIONALITY, KERNEL_TRUNCATION/ISURFACE, KERNEL_TRUNCATION/FACTOR, KERNEL_TRUNCATION/IPAD

References