&FORCE_EVAL
  METHOD FIST
  &MM
    &FORCEFIELD
       PARM_FILE_NAME ../sample_pot/acn.pot 
       PARMTYPE CHM
       &CHARGE
        ATOM CT
        CHARGE -0.479
       &END CHARGE
       &CHARGE
        ATOM YC
        CHARGE  0.481
       &END CHARGE
       &CHARGE
        ATOM YN
        CHARGE -0.532
       &END CHARGE
       &CHARGE
        ATOM HC
        CHARGE  0.177
       &END CHARGE
    &END FORCEFIELD
    &POISSON
      &EWALD
        EWALD_TYPE SPME
        ALPHA .44
        GMAX 32
        O_SPLINE 6
      &END EWALD
    &END POISSON
    &PRINT
      &FF_INFO
        SPLINE_DATA
      &END
    &END
  &END MM
  &SUBSYS
    &CELL
      ABC 27.0 27.0 27.0
    &END CELL
    &TOPOLOGY
      CONNECTIVITY GENERATE
      &GENERATE
       BONDPARM_FACTOR 1.31
      &END
      &DUMP_PDB
      &END
      &DUMP_PSF
      &END
      MOL_CHECK
      COORD_FILE_NAME ../sample_pdb/acn.pdb
      COORDINATE      pdb
    &END TOPOLOGY
  &END SUBSYS
  STRESS_TENSOR ANALYTICAL
&END FORCE_EVAL
&GLOBAL
  PROJECT acn
  RUN_TYPE md
  IOLEVEL  LOW
&END GLOBAL
&MOTION
  &MD
    ENSEMBLE NPT_I
    STEPS 5
    TIMESTEP 0.5
    TEMPERATURE 300
    &BAROSTAT
      PRESSURE 0.
      TIMECON 1000
    &END BAROSTAT
    &THERMOSTAT
      &NOSE
        LENGTH 3
        YOSHIDA 3
        TIMECON 1000
        MTS 2
      &END NOSE
    &END
  &END MD
&END MOTION
