&FORCE_EVAL
  METHOD FIST
  &MM
    &FORCEFIELD
      &CHARGE
        ATOM S
        CHARGE 1.2
      &END CHARGE
      &CHARGE
        ATOM F
        CHARGE -0.2
      &END CHARGE
      &BOND
        ATOMS F S
        KIND HARMONIC
        K [hartree*bohr^-2] 0.5
        R0 [angstrom] 1.564
      &END BOND
      &BEND
        ATOMS F S F
        KIND HARMONIC
        K [hartree*rad^-2] 0.2
        THETA0 [deg] 100
      &END BEND
      &NONBONDED
        &LENNARD-JONES
          ATOMS F F
          EPSILON 0.0
          SIGMA 1.0
        &END LENNARD-JONES
        &LENNARD-JONES
          ATOMS S F
          EPSILON 0.0
          SIGMA 1.0
        &END LENNARD-JONES
        &LENNARD-JONES
          ATOMS S S
          EPSILON 0.0
          SIGMA 1.0
        &END LENNARD-JONES
      &END NONBONDED
    &END FORCEFIELD
    &POISSON
      PERIODIC NONE
      &EWALD
        EWALD_TYPE NONE
        ALPHA .36
        GMAX 51
      &END EWALD
    &END POISSON
  &END MM
  &SUBSYS
    &CELL
      ABC 20.0 20.0 20.0
      PERIODIC NONE
    &END CELL
    &COORD
      S 0.0 0.0 0.0
      F 1.564 0.0 0.0
      F -1.564 0.0 0.0
      F 0.0 1.564 0.0
      F 0.0 -1.564 0.0
      F 0.0 0.0 1.564
      F 0.0 0.0 -1.564
    &END COORD
    &TOPOLOGY
      &GENERATE
        CREATE_MOLECULES
        &ANGLE REMOVE
          ATOMS 2 1 3
          ATOMS 4 1 5
          ATOMS 6 1 7
        &END ANGLE
      &END GENERATE
    &END TOPOLOGY
  &END SUBSYS
&END FORCE_EVAL
&GLOBAL
  PROJECT SF6_topo_excl
  PRINT_LEVEL LOW
  RUN_TYPE ENERGY_FORCE
&END GLOBAL
