&FORCE_EVAL
  METHOD Quickstep
  &DFT
    BASIS_SET_FILE_NAME BASIS_SET
    POTENTIAL_FILE_NAME POTENTIAL
    &MGRID
      CUTOFF 50
    &END MGRID
    &QS
    &END QS
    &SCF
      MAX_SCF 5
      &OT ON
      &END OT
    &END SCF
    &XC
      &XC_FUNCTIONAL PADE
      &END XC_FUNCTIONAL
    &END XC
  &END DFT
  &SUBSYS
    &CELL
      ABC 6.0 6.0 8.0
    &END CELL
    &COORD
    C         -0.2558206925       -0.0449868417        0.6850619693
    C         -0.2214915625       -0.0386665897       -0.6514432536
    H         -0.4100752923        0.8714166677        1.2581094627
    H         -0.1401850725       -0.9650616559        1.2579495323
    H         -0.0795226532       -0.9560364450       -1.2252531634
    H         -0.3538336094        0.8817708920       -1.2228724740
    &END COORD
    &KIND H
      BASIS_SET SZV-GTH-PADE
      POTENTIAL GTH-PADE-q1
    &END KIND
    &KIND C
      BASIS_SET SZV-GTH-PADE
      POTENTIAL GTH-PADE-q4
    &END KIND
    &COLVAR
       &BOND_ROTATION
        &POINT
          TYPE GEO_CENTER
          ATOMS 1
        &END
        &POINT
          TYPE GEO_CENTER
          ATOMS 2
        &END
        &POINT
          TYPE GEO_CENTER
          ATOMS 3 4
        &END
        &POINT
          TYPE GEO_CENTER
          ATOMS 5 6
        &END
          P1_BOND1 3
          P2_BOND1 4
          P1_BOND2 1
          P2_BOND2 2
       &END BOND_ROTATION
    &END COLVAR
  &END SUBSYS
&END FORCE_EVAL
&GLOBAL
  PROJECT C2H4-meta
  RUN_TYPE MD
  PRINT_LEVEL MEDIUM
&END GLOBAL
&MOTION
  &MD
    ENSEMBLE NVE
    STEPS 3
    TIMESTEP 0.1
    TEMPERATURE 300.0
  &END MD
  &FREE_ENERGY
    &METADYN
      DO_HILLS
      #LAGRANGE
      NT_HILLS 1
      WW 1.0e-2
      # Metavar ref0 e ref1
      &METAVAR
        LAMBDA 0.1
        MASS 10.0
        SCALE 0.1
        COLVAR 1
      &END METAVAR
    &END METADYN
  &END
&END MOTION
