# MULTIPOLE

This section is used to set up the decoupling of QM periodic images with the use of density derived atomic point charges. Switched on by default even if not explicitly given. Can be switched off if e.g. QM and MM box are of the same size. [Edit on GitHub]

Subsections

- CHECK_SPLINE
- INTERPOLATOR
- PROGRAM_RUN_INFO

## Keywords

- SECTION_PARAMETERS

- ANALYTICAL_GTERM

- EWALD_PRECISION

- NGRIDS

- RCUT

## Keyword descriptions

SECTION_PARAMETERS: enum = ON

  Lone keyword: `ON`

  Usage: ON

  Valid values:

  - `ON` switch on MULTIPOLE section

  - `OFF` switch off MULTIPOLE section

  Defines the usage of the multipole section [Edit on GitHub]

ANALYTICAL_GTERM: logical = F

  Lone keyword: `T`

  Usage: ANALYTICAL_GTERM <LOGICAL>

  Evaluates the Gterm in the Ewald Scheme analytically instead of using Splines. [Edit on GitHub]

EWALD_PRECISION: real = 1.00000000E-006 [hartree]

  Usage: EWALD_PRECISION {real}

  Precision achieved in the Ewald sum. [Edit on GitHub]

NGRIDS: integer[3] = 50 50 50

  Usage: NGRIDS <integer> <integer> <integer>

  Specifies the number of grid points used for the Interpolation of the G-space term [Edit on GitHub]

RCUT: real = [angstrom]

  Usage: RCUT {real}

  Real space cutoff for the Ewald sum. [Edit on GitHub]