d1: DISTANCE ATOMS=1,10
d2: DISTANCE ATOMS=50,40
mdf: PBMETAD ARG=d1,d2 SIGMA=0.1,0.2 HEIGHT=1.0 PACE=10 TEMP=300 BIASFACTOR=5 FILE=HILLS.0,HILLS.1 RESTART=YES
mdg: PBMETAD ARG=d1,d2 SIGMA=0.1,0.2 HEIGHT=1.0 PACE=10 TEMP=300 BIASFACTOR=5 FILE=HILLS.a,HILLS.b GRID_WFILES=grid0,grid1 GRID_RFILES=grid0,grid1 GRID_WSTRIDE=10 GRID_MIN=0,0 GRID_MAX=10,10 RESTART=YES
