KERNEL TRUNCATION/IDIMENSIONALITY: Difference between revisions

From VASP Wiki
No edit summary
No edit summary
 
(20 intermediate revisions by 2 users not shown)
Line 1: Line 1:
{{TAGDEF|KERNEL_TRUNCATION/IDIMENSIONALITY_CUTOFF| 0 {{!}} 2 {{!}} 3 | 3}}
{{TAGDEF|KERNEL_TRUNCATION/IDIMENSIONALITY| 0 {{!}} 2 {{!}} 3 | 3}}
 
Description: {{TAG|KERNEL_TRUNCATION/IDIMENSIONALITY}} specifies the boundary condition used to compute the hartree and ionic potential.


Description: {{TAG|KERNEL_TRUNCATION/IDIMENSIONALITY_CUTOFF}} specifies the boundary condition used to compute the hartree and ionic potential
----
----


If {{TAG|KERNEL_TRUNCATION/LTRUNCATE_KERNEL}} = T, {{TAG|KERNEL_TRUNCATION/IDIMENSIONALITY_CUTOFF}} determines the boundary condition that is used to compute the local potential. The default value of 3 implies that the system is periodic in all dimensions, i.e. there is no influence of kernel truncation on the resulting energies and forces.
If {{TAG|KERNEL_TRUNCATION/LTRUNCATE}} = T, {{TAG|KERNEL_TRUNCATION/IDIMENSIONALITY}} determines the boundary condition that is used to compute the local potential.
The default value of 3 implies that the system is periodic in all dimensions, i.e. there is no influence of kernel truncation on the resulting energies and forces.
Setting {{TAG|KERNEL_TRUNCATION/IDIMENSIONALITY}} to either 0 or 2 uses the 0D and 2D truncated kernel respectively.{{cite|vijay:arxiv:2024}}{{cite|rozzi:prb:2006}}{{cite|sohier:prb:2017}}
These kernels create 0D (i.e. no periodic interactions, as is the case of molecules) and 2D (i.e. periodic interactions only in two dimensions, as in the case for surfaces).
{{NB|mind|IF {{TAG|KERNEL_TRUNCATION/LTRUNCATE}} is switched off, all other KERNEL_TRUNCATION tags, i.e. {{TAG|KERNEL_TRUNCATION/IDIMENSIONALITY}}, {{TAG|KERNEL_TRUNCATION/LCOARSEN}}, and {{TAG|KERNEL_TRUNCATION/ISURFACE}} will be ignored.}}
 
== {{TAG|KERNEL_TRUNCATION/IDIMENSIONALITY}} = 0 ==
Consider using the option when computing energies and forces of atoms and molecules.
Recommended {{FILE|INCAR}} tags to be used with option are
  KERNEL_TRUNCATION {
        LTRUNCATE      = T
        IDIMENIONALITY = 0
        LCOARSEN      = T
  }
 
== {{TAG|KERNEL_TRUNCATION/IDIMENSIONALITY}} = 2 ==
Use this option when computing the energies and forces of 2D and quasi-2D systems, such as 2D materials and surfaces. We suggest setting the following {{FILE|INCAR}} tags for a surface that is oriented along the z-axis
  KERNEL_TRUNCATION {
        LTRUNCATE      = T
        IDIMENIONALITY = 2
        LCOARSEN      = T
        ISURFACE      = 3
  }
 
== Related tags and articles ==
{{TAG|KERNEL_TRUNCATION/LTRUNCATE}},
{{TAG|KERNEL_TRUNCATION/LCOARSEN}},
{{TAG|KERNEL_TRUNCATION/ISURFACE}}
 
== References ==
 
[[Category:INCAR tag]]

Latest revision as of 08:50, 19 December 2024

KERNEL_TRUNCATION/IDIMENSIONALITY = 0 | 2 | 3
Default: KERNEL_TRUNCATION/IDIMENSIONALITY = 3 

Description: KERNEL_TRUNCATION/IDIMENSIONALITY specifies the boundary condition used to compute the hartree and ionic potential.


If KERNEL_TRUNCATION/LTRUNCATE = T, KERNEL_TRUNCATION/IDIMENSIONALITY determines the boundary condition that is used to compute the local potential. The default value of 3 implies that the system is periodic in all dimensions, i.e. there is no influence of kernel truncation on the resulting energies and forces. Setting KERNEL_TRUNCATION/IDIMENSIONALITY to either 0 or 2 uses the 0D and 2D truncated kernel respectively.[1][2][3] These kernels create 0D (i.e. no periodic interactions, as is the case of molecules) and 2D (i.e. periodic interactions only in two dimensions, as in the case for surfaces).

Mind: IF KERNEL_TRUNCATION/LTRUNCATE is switched off, all other KERNEL_TRUNCATION tags, i.e. KERNEL_TRUNCATION/IDIMENSIONALITY, KERNEL_TRUNCATION/LCOARSEN, and KERNEL_TRUNCATION/ISURFACE will be ignored.

KERNEL_TRUNCATION/IDIMENSIONALITY = 0

Consider using the option when computing energies and forces of atoms and molecules. Recommended INCAR tags to be used with option are

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

KERNEL_TRUNCATION/IDIMENSIONALITY = 2

Use this option when computing the energies and forces of 2D and quasi-2D systems, such as 2D materials and surfaces. We suggest setting the following INCAR tags for a surface that is oriented along the z-axis

 KERNEL_TRUNCATION {
       LTRUNCATE      = T
       IDIMENIONALITY = 2
       LCOARSEN       = T
       ISURFACE       = 3
 }

Related tags and articles

KERNEL_TRUNCATION/LTRUNCATE, KERNEL_TRUNCATION/LCOARSEN, KERNEL_TRUNCATION/ISURFACE

References