@SET NREP 1
&FORCE_EVAL
  &DFT
    &POISSON
      &EWALD
        ALPHA 1.0
        EWALD_TYPE SPME
        GMAX 25
      &END EWALD
    &END POISSON
    &QS
      METHOD xTB
      &XTB
        DO_EWALD T
        &PARAMETER
          DISPERSION_PARAMETER_FILE dftd3.dat
        &END PARAMETER
      &END XTB
    &END QS
    &SCF
      EPS_SCF 1.e-6
      MAX_SCF 100
      SCF_GUESS MOPAC
      &MIXING
        ALPHA 0.10
        METHOD DIRECT_P_MIXING
      &END MIXING
    &END SCF
  &END DFT
  &SUBSYS
    &CELL
      ABC 5.431 5.431 5.431
      MULTIPLE_UNIT_CELL ${NREP} ${NREP} ${NREP}
    &END CELL
    &COORD
      SCALED
      Si     0.000000    0.000000    0.000000
      Si     0.490000    0.500000    0.000000
      Si     0.500000    0.000000    0.500000
      Si     0.000000    0.500000    0.500000
      Si     0.255000    0.250000    0.250000
      Si     0.250000    0.755000    0.750000
      Si     0.750000    0.250000    0.755000
      Si     0.750000    0.750000    0.255000
    &END COORD
    &TOPOLOGY
      MULTIPLE_UNIT_CELL ${NREP} ${NREP} ${NREP}
    &END TOPOLOGY
  &END SUBSYS
&END FORCE_EVAL

&GLOBAL
  PRINT_LEVEL LOW
  PROJECT Si
  RUN_TYPE GEO_OPT
&END GLOBAL

&MOTION
  &GEO_OPT
    MAX_DR 0.0001
    MAX_FORCE 0.00001
    MAX_ITER 2
    OPTIMIZER BFGS
    RMS_DR 0.00003
    RMS_FORCE 0.000003
  &END GEO_OPT
&END MOTION
