d1: COORDINATION GROUPA=1-108 GROUPB=109-216   SWITCH={RATIONAL R_0=0.34112 NN=6 MM=12 D_MAX=0.36}
d:  COMBINE ARG=d1 COEFFICIENTS=0.00925925926 PERIODIC=NO


METAD ...
 LABEL=metad
 ARG=d
 SIGMA=0.5
 HEIGHT=15
 PACE=500     
 GRID_MIN=1
 GRID_MAX=10
 GRID_BIN=2500
... METAD

UPPER_WALLS ARG=d AT=9 KAPPA=15000 EXP=2 EPS=1 OFFSET=0 LABEL=uwall
LOWER_WALLS ARG=d AT=2 KAPPA=15000 EXP=2 EPS=1 OFFSET=0 LABEL=dwall

PRINT ARG=* FILE=colvar_550 STRIDE=50

ENDPLUMED