# VIRTUAL_SITE

Section can be repeated.

This section is used to set a virtual interaction-site constraint. [Edit on GitHub]

Subsections

- RESTRAINT

## Keywords

- ATOMS

- EXCLUDE_MM

- EXCLUDE_QM

- INTERMOLECULAR

- MOLECULE

- MOLNAME

- PARAMETERS

## Keyword descriptions

ATOMS: integer[4]

  Usage: ATOMS 1 2 3 4

  Atoms’ index on which apply the constraint (v i j k), first is virtual site [Edit on GitHub]

EXCLUDE_MM: logical = F

  Lone keyword: `T`

  Usage: EXCLUDE_MM <LOGICAL>

  Does not apply the constraint to the MM region within a QM/MM calculation [Edit on GitHub]

EXCLUDE_QM: logical = F

  Lone keyword: `T`

  Usage: EXCLUDE_QM <LOGICAL>

  Does not apply the constraint to the QM region within a QM/MM calculation [Edit on GitHub]

INTERMOLECULAR: logical = F

  Lone keyword: `T`

  Usage: INTERMOLECULAR <LOGICAL>

  Specify if the constraint/restraint is intermolecular. [Edit on GitHub]

MOLECULE: integer

  Aliases: MOL

  Usage: MOL {integer}

  Specifies the molecule number on which constraint will be applied. MOLECULE and MOLNAME keyword exclude themself mutually. [Edit on GitHub]

MOLNAME: string

  Aliases: SEGNAME

  Usage: MOLNAME {character}

  Specifies the name of the molecule on which the constraint will be applied. [Edit on GitHub]

PARAMETERS: real[2] = [internal_cp2k]

  Usage: PARAMETERS {real} {real}

  The constrained parameters’ values to construct virtual site. r_v=ar_ij+br_kj [Edit on GitHub]