# S2_RESTRAINT

Use S2 in a re/constraint (OT only) [Edit on GitHub]

## Keywords

- FUNCTIONAL_FORM

- STRENGTH

- TARGET

## Keyword descriptions

FUNCTIONAL_FORM: enum = RESTRAINT

  Usage: FUNCTIONAL_FORM RESTRAINT

  Valid values:

  - `RESTRAINT` Harmonic potential: s*(q-t)**2

  - `CONSTRAINT` Constraint form: s*(q-t)

  Specifies the functional form of the term added [Edit on GitHub]

STRENGTH: real = 1.00000000E-001

  Usage: STRENGTH {real}

  force constant of the restraint [Edit on GitHub]

TARGET: real = 1.00000000E+000

  Usage: TARGET {real}

  target value of the restraint [Edit on GitHub]