[CP2K-user] [CP2K:21877] Inquiry about constrained MD in CP2K

[Jianzhi]

 I am running a constrained MD simulation where atom A is driven to 
approach atom B, with atom B fixed during the simulation. The relevant 
parts of my input are as follows: 
    &COLVAR
      &DISTANCE
        ATOMS 289 674
      &END DISTANCE
    &END COLVAR
......
  &CONSTRAINT
    &FIXED_ATOMS
      COMPONENTS_TO_FIX XYZ
      LIST 289
    &END FIXED_ATOMS
    &COLLECTIVE
      INTERMOLECULAR T
      COLVAR 1
      TARGET [angstrom] 31.9081
      TARGET_GROWTH [angstrom*fs^-1] -0.0008
    &END COLLECTIVE
    &LAGRANGE_MULTIPLIERS ON
       COMMON_ITERATION_LEVELS 1
       FILENAME ./lagrange.dat
    &END LAGRANGE_MULTIPLIERS
    SHAKE_TOLERANCE 0.00001
  &END CONSTRAINT
.......
*Question 1*: Why do the Shake Lagrangian multipliers appear with four 
components, for example:  
Shake  Lagrangian Multipliers:             0.188781938    0.000000000   
 0.000000000    0.000000000
In another test case I ran, only a single value was printed. What 
determines whether the output has one or multiple components? 
*Question 2*: Are the units of the Shake Lagrangian multipliers given in 
Hartree/Bohr, regardless of the fact that the TARGET and TARGET_GROWTH 
values were specified in angstroms and angstrom/fs? I am asking because the 
free energy obtained from integrating the Shake Lagrangian multipliers 
appears to be unphysically large.

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