PM6 - MTD - Matrix diagonalization failed

[Francesco]

Hi,
trying to do a PM6-metadynamics study with a transition-metal
complexes I've obtained a lot of times the following error, saying
that the "Matrix diagonalization failed".
With the same starting point I obtain this error at the same timestep
each time.

Below the output error, I put the PM6 DFT input shell I'm using.

Thanks in advance for all your suggestions.
Francesco


p.s.
I've just recompiled the sopt executable, but I've obtained the same
error also with a previous popt executable (21-07-2008)

################################################
 SCF WAVEFUNCTION OPTIMIZATION

  Step  Update method              Time         Convergence
Total energy
 
-----------------------------------------------------------------------------
     1  Mixing/Diag.   0.40E+00    0.07        0.0542186027
-191.8978849225


 *
 *** ERROR in cp_fm_syevd (MODULE cp_fm_diag)  ***
 *


 *** Matrix diagonalization failed  ***


 *** Program stopped at line number 151 of MODULE cp_fm_diag  ***

 ===== Routine Calling Stack =====

            9 cp_fm_syevd
            8 simple_eigensolver
            7 scf_env_do_scf_inner_loop
            6 scf_env_do_scf
            5 qs_energies
            4 qs_forces
            3 velocity_verlet
            2 qs_mol_dyn_low
            1 CP2K

##########################
PM6 DFT shell - input
##########################
  &DFT
     &POISSON
       POISSON_SOLVER WAVELET
       PERIODIC NONE
     &END POISSON
    &QS
      METHOD PM6
      &SE
        ANALYTICAL_GRADIENTS F
        STO_NG 6
      &END SE
    &END QS
    &SCF
      SCF_GUESS MOPAC
      EPS_SCF 1.0E-04
      &PRINT
        &RESTART OFF
        &END RESTART
      &END PRINT
    &END SCF
  &END DFT

################################################