[CP2K-user] Weird behavior for Lagrange Multipliers

[Alejandro Ramos]

Dear CP2K community,

I'm performing a constrained MD simulation to use later the Lagrange 
Multipliers to compute the force along some reaction path. I'm constraining 
the distances between all atoms in a 33 atoms molecule. However, if I 
compute the norm of the vector formed by all Lagrange Multipliers in each 
step, I get the behavior shown in the plot attached. This norm 
monotonically increases during the simulation and reset itself when I 
continue the run using a restart file, and of course  you can see the same 
pattern replicated if I compute the force along the reaction path. I expect 
that the norm of the Lagrange Multipliers should show some equilibrated 
behavior and not have this jumps every time I continue the simulation with 
the restart file. Does anyone have a clue why is this happening? What could 
be wrong in the input file? 

I'm attaching the graph showing the norm of the Lagrange Multipliers, time 
scale is in picoseconds, and Lagrange Multipliers units are in Hartree/Bohr.

I'm also attaching the input file.

Thanks in advance,

Alejandro.
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