@SET METHOD = QMMM # FIST all classical treatment # QS all quantum treatment

&GLOBAL
  FLUSH_SHOULD_FLUSH
  PRINT_LEVEL LOW
  PROJECT KCl
  RUN_TYPE GEO_OPT
&END GLOBAL

&FORCE_EVAL
  METHOD $METHOD
  @include QS.inc
  @include MM.inc
  &QMMM
    #this defines the QS cell in the QMMM calc
    &CELL
      ABC 12.6 15.0 12.6
      PERIODIC XZ
    &END CELL
    ECOUPL GAUSS # use GEEP method
    NOCOMPATIBILITY
    USE_GEEP_LIB 6  # use GEEP method
    &PERIODIC # apply periodic potential
      #in this case QM box = MM box in XZ so turn
      #off coupling/recoupling of the QM multipole
      &MULTIPOLE OFF
      &END
    &END PERIODIC
    #these are just the ionic radii of K Cl
    #but should be treated as parameters in general
    #fit to some physical property

    &MM_KIND Cl
      RADIUS 1.67
    &END MM_KIND
    #define the model
    &QM_KIND K
      MM_INDEX 25..32 41..48
    &END QM_KIND
    &QM_KIND Cl
      MM_INDEX 17..24 33..40
    &END QM_KIND
  &END QMMM

  &SUBSYS
    #this defines the cell of the whole system
    #must be orthorhombic, I think
    &CELL
      ABC 12.6 100.0 12.6
    &END CELL
    &TOPOLOGY
      COORD_FILE_NAME kcl.xyz
      COORD_FILE_FORMAT XYZ
      &GENERATE
         &ISOLATED_ATOMS
         #ignores bonds dihedrals etc in classical part
            LIST 1..48
         &END
      &END
    &END
    &KIND K
      ELEMENT K
      BASIS_SET DZVP-MOLOPT-SR-GTH
      POTENTIAL GTH-PBE-q9
    &END KIND
    &KIND Cl
      BASIS_SET DZVP-MOLOPT-GTH
      POTENTIAL GTH-PBE-q7
    &END
  &END SUBSYS
&END FORCE_EVAL

#should be able to use most motion sections
#analytic stress tensor not available, I think
@include motion.inc