Metadynamics Questions: COLVARs yielding unexpected values.

[Christopher O'Brien]

CP2K users,
I am obtaining very unexpected results from the COLVARS of the METADYNAMICS 
module. I had to piece together an input from the mail list and what I 
could learn from the manual, but I think I have all of the relevant 
additional input required for METADYNAMICS. Please tell me if I'm wrong. 

I am obtaining very large COLVAR distances for variable 1 and entirely too 
small ones for variable 2. COLVAR 1 should be around 1.7A, but it ranges 
from 7.99 to 11.17 (Bohr?). COLVAR 2 should be about 1.5A, but it appears 
to vary from 3.621-6.252 (Bohr?). (Coordination, COLVAR 3, varies from -0.2 
to 0.3, but I have not idea what it should be). The range of distances were 
reported in by the fes.sopt code which I ran with the options:
fes.sopt -ndim 3 -find-minima -cp2k -file xxx.restart

I am also interested to learn if METADYNAMICS can be restarted. There are a 
lot of unexplained keywords that have something to do with restarting 
METADYNAMICS in the manual, but I don't know if we have to use them. 

I have included the relevant section from the &MOTION input section and the 
&FORCE_EVAL/&SUBSYS input section below:

&MOTION  
   &FREE_ENERGY

   METHOD METADYN 

   &METADYN 

    DO_HILLS .TRUE. 

    WW [hartree] 1.0E-3 

    NT_HILLS 15 


    &METAVAR 

     COLVAR 1 

     SCALE 0.08 

    &END METAVAR 


    &METAVAR 

     COLVAR 2 

     SCALE 0.08 

    &END METAVAR 

    &METAVAR 

     COLVAR 3 

     SCALE 0.08 

    &END METAVAR 

    &PRINT 

    &COLVAR MEDIUM 
      &EACH 

        METADYNAMICS 1 

        MD 15 

      &END EACH 

      FILENAME xxx_colvar 

     &END COLVAR 

    &END PRINT 

   &END METADYN 

   &FREE_ENERGY_INFO MEDIUM 

     &EACH 

       METADYNAMICS 1 

       MD 15 

     &END EACH 

     FILENAME xxx_freeenergy 

   &END FREE_ENERGY_INFO 

  &END FREE_ENERGY

&END MOTION

And the &SUBSYS section containing the COLVARS:
  &SUBSYS

    &CELL 

      ABC 12.97658 12.90794 12.97688 

      PERIODIC XYZ 

    &END CELL 

    &COLVAR 

     !P to F

     &DISTANCE 

      ATOMS 11 17 

     &END DISTANCE 

    &END COLVAR 

    &COLVAR 

     !P to O

     &DISTANCE 

      ATOMS 11 9 

     &END DISTANCE 

    &END COLVAR 


    &COLVAR 

     !see 10.1021/jp301490k for ND NN R0 parameter meaning 

     ! P to O in water 

     &COORDINATION 

      ND 12 

      NN 6 

      R0 [bohr] 3.0 

      KINDS_FROM P 

      KINDS_TO Ow 

     &END COORDINATION 

    &END COLVAR




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