Gromacs-CP2k energy minimization

Hi everyone,

I am trying to perform a QM/MM geometry optimization after an MD simulation using the Gromacs-Cp2k interface. I would like to use the L-BFGS integrator for minimization, but I receive the following error:

Fatal error:

The combination of constraints and L-BFGS minimization is not implemented."

Either do not use constraints or use a different minimizer (e.g., steepest descent).

I understand that this algorithm is not implemented with constraints. Even when I set constraints = none, I get this error. How can I overcome this error?

Any suggestions are highly appreciated. Thank you in advance.