# IMAGE_CHARGE

References: Golze2013

Inclusion of polarization effects within the image charge approach for systems where QM molecules are physisorbed on e.g. metal surfaces described by MM. This correction introduces only a very small overhead. QM box size has to be equal to MM box size. [Edit on GitHub]

Subsections

- ERI_MME

## Keywords

- DETERM_COEFF

- EXT_POTENTIAL

- IMAGE_MATRIX_METHOD

- IMAGE_RESTART_FILE_NAME

- MM_ATOM_LIST

- RESTART_IMAGE_MATRIX

- WIDTH

## Keyword descriptions

DETERM_COEFF: enum = CALC_MATRIX

  Usage: DETERM_COEFF ITERATIVE

  Valid values:

  - `CALC_MATRIX` Calculates image matrix and solves linear set of equations

  - `ITERATIVE` Uses an iterative scheme to calculate the coefficients

  Mentions: ⭐Image Charges

  Specifies how the coefficients are determined. [Edit on GitHub]

EXT_POTENTIAL: real = 0.00000000E+000 [volt]

  Usage: EXT_POTENTIAL <real>

  Mentions: ⭐Image Charges

  External potential applied to the metal electrode [Edit on GitHub]

IMAGE_MATRIX_METHOD: enum = MME

  Usage: IMAGE_MATRIX_METHOD MME

  Valid values:

  - `GPW` Uses Gaussian Plane Wave method [Golze2013]

  - `MME` Uses MiniMax-Ewald method (ERI_MME subsection)

  Mentions: ⭐Image Charges

  Method for calculating the image matrix. [Edit on GitHub]

IMAGE_RESTART_FILE_NAME: string

  Usage: IMAGE_RESTART_FILE_NAME <FILENAME>

  File name where to read the image matrix used as preconditioner in the iterative scheme [Edit on GitHub]

MM_ATOM_LIST: integer[ ]

  Keyword can be repeated.

  Usage: MM_ATOM_LIST 1 2 3 or 1..3

  Mentions: ⭐Image Charges

  List of MM atoms carrying an induced Gaussian charge. If this keyword is not given, all MM atoms will carry an image charge. [Edit on GitHub]

RESTART_IMAGE_MATRIX: logical = F

  Lone keyword: `T`

  Usage: RESTART_IMAGE_MATRIX

  Mentions: ⭐Image Charges

  Restart the image matrix. Useful when calculating coefficients iteratively (the image matrix is used as preconditioner in that case) [Edit on GitHub]

WIDTH: real = 3.00000000E+000 [angstrom^-2]

  Usage: WIDTH <real>

  Mentions: ⭐Image Charges

  Specifies the value of the width of the (induced) Gaussian charge distribution carried by each MM atom. [Edit on GitHub]