How to fix NaN error and numerical derivative warning (0.100000E+31) in wtMetaD?

[Qi Zhang]

Hi CP2K users,

I am running a Well-Tempered Metadynamics simulation, but it fails at the very first step (0.00000000 ps) with NaN in the metadynLog file.

Meanwhile, the stdout shows the following warning:

*** WARNING in colvar_methods.F:4530 :: ASSERTION (cond) failed at line  ***
*** 4531           Error (0.100000E+31) in computing numerical          ***
*** derivatives larger then(0.100000E-11) .                             ***

  Here is how I defined my CV section (nesting two &COORDINATION blocks under &COMBINE_COLVAR):

&COLVAR
         &COMBINE_COLVAR
            &COLVAR
               &COORDINATION
                  KINDS_FROM  Ge
                  KINDS_TO   Cl
                  R_0 [angstrom]  2.80
                  NN  12
                  ND  24
              &END COORDINATION
           &END COLVAR
           &COLVAR
             &COORDINATION
                ATOMS_FROM  1
                ATOMS_TO   3 5 7 9
                R_0 [angstrom]  2.30
                NN  12
                ND  24
              &END COORDINATION
            &END COLVAR
            FUNCTION  CV2-CV1
            VARIABLES  CV1 CV2
         &END COMBINE_COLVAR

    &END COLVAR  

Does anyone know what is causing this NaN and derivative error? How should I modify my input file to fix this issue and get the simulation running properly?

I have attached my full input (.inp) and output (.out) files for your reference.

Thank you for your help!

Best regards,

Qi Zhang