&GLOBAL
  PREFERRED_DIAG_LIBRARY ScaLAPACK
  PRINT_LEVEL medium
  PROJECT Si_direct_cell_opt
  RUN_TYPE CELL_OPT
&END GLOBAL

&MOTION
  &CELL_OPT
    CONSTRAINT none
    EXTERNAL_PRESSURE [bar] 1.0
    KEEP_ANGLES no
    KEEP_SYMMETRY no
    MAX_DR 0.00001
    MAX_FORCE 0.000001
    MAX_ITER 400
    OPTIMIZER BFGS
    PRESSURE_TOLERANCE [bar] 10.0
    RMS_DR 0.000003
    RMS_FORCE 0.0000003
    &BFGS
      TRUST_RADIUS 0.1
      USE_MODEL_HESSIAN no
      USE_RAT_FUN_OPT on
    &END BFGS
  &END CELL_OPT
  &PRINT
    &CELL on
    &END CELL
    &RESTART on
      BACKUP_COPIES 0
    &END RESTART
    &RESTART_HISTORY off
    &END RESTART_HISTORY
  &END PRINT
&END MOTION

&FORCE_EVAL
  METHOD FIST
  STRESS_TENSOR ANALYTICAL
  &MM
    &FORCEFIELD
      &NONBONDED
        &TERSOFF
          A 1.8308E3
          ALPHA 0.00
          ATOMS Si Si
          B 4.7118E2
          BETA 1.0999E-6
          BIGD 0.15
          BIGR 2.85
          C 1.0039E5
          D 1.6218E1
          H -5.9826E-1
          LAMBDA1 2.4799
          LAMBDA2 1.7322
          LAMBDA3 1.7322
          N 7.8734E-1
          RCUT 10.0
        &END TERSOFF
      &END NONBONDED
      &SPLINE
        EPS_SPLINE 1.0E-8
      &END SPLINE
    &END FORCEFIELD
    &POISSON
      &EWALD
        EWALD_TYPE none
      &END EWALD
    &END POISSON
  &END MM
  &PRINT
    &STRESS_TENSOR
    &END STRESS_TENSOR
  &END PRINT
  &SUBSYS
    &CELL
      ABC 3.850 3.850 6.366
      ANGLES 90.0 90.0 120.0
      MULTIPLE_UNIT_CELL 3 3 3
      PERIODIC XYZ
    &END CELL
    &COORD
      SCALED
      Si   1/3  2/3  0.063
      Si   1/3  2/3  0.437
      Si   2/3  1/3  0.563
      Si   2/3  1/3  0.937
    &END COORD
    &PRINT
      &ATOMIC_COORDINATES
      &END ATOMIC_COORDINATES
      &CELL
      &END CELL
    &END PRINT
    &TOPOLOGY
      CONNECTIVITY OFF
      MULTIPLE_UNIT_CELL 3 3 3
    &END TOPOLOGY
  &END SUBSYS
&END FORCE_EVAL
