plumed input for metad alphabeta cv

metad_alphabeta.dat

# Activate MOLINFO functionalities
MOLINFO STRUCTURE=ref.pdb

# -0.994838 = -57.0 deg (phi)
ALPHABETA ...
ATOMS1=@phi-2 REFERENCE=-0.994838
ATOMS2=@phi-3
ATOMS3=@phi-4
ATOMS4=@phi-5
ATOMS5=@phi-6
ATOMS6=@phi-7
ATOMS7=@phi-8
ATOMS8=@phi-9
ATOMS9=@phi-10
label=alphaphi
...

# -0.820305 = -47.0 deg (psi)
ALPHABETA ...
ATOMS1=@psi-2 REFERENCE=-0.820305
ATOMS2=@psi-3
ATOMS3=@psi-4
ATOMS4=@psi-5
ATOMS5=@psi-6
ATOMS6=@psi-7
ATOMS7=@psi-8
ATOMS8=@psi-9
ATOMS9=@psi-10
label=alphapsi
...

# Activate well-tempered metadynamics
metad: METAD ...
   ARG=alphaphi,alphapsi

   # Deposit a Gaussian every 500 time steps, with initial height equal to 1.2 kJ/mol
   PACE=500 HEIGHT=1.2

   # The bias factor should be wisely chosen
   BIASFACTOR=5

   # Gaussian width (sigma) should be chosen based on CV fluctuation in unbiased run
   SIGMA=0.25,0.25

   # Gaussians will be written to file and also stored on grid
   FILE=HILLS
...

# Print both collective variables on COLVAR file every 10 steps
PRINT ARG=alphaphi,alphapsi FILE=COLVAR STRIDE=10