# [CP2K-user] convergence problem

alberto albesan... at gmail.com
Sun May 30 21:09:07 UTC 2021

```Dear cp2k users,
I am doing the geometry optimization of a configuration (supercell
containing 4 molecules of Fe(CO)5 with symmetry C2/c and Z=4) but the
energy is locked on a value and is not decreasing.
How can I solve this problem?
Should I use a higher CUTOFF value?

*******************************************************************************
***                 BRENT   - NUMBER OF ENERGY EVALUATIONS :       1
***
*******************************************************************************

--------  Informations at step =   186 ------------
Optimization Method        =                   SD
Total Energy               =      -927.5280017548
Real energy change         =         0.0000000000
Decrease in energy         =                   NO
Used time                  =             2410.831

Convergence check :
Max. step size             =         0.0000000000
Conv. limit for step size  =         0.0000010000
Convergence in step size   =                  YES
RMS step size              =         0.0000000000
Conv. limit for RMS step   =         0.0000010000
Convergence in RMS step    =                  YES
Conv. limit for gradients  =         0.0000010000
Conv. limit for RMS grad.  =         0.0000010000
---------------------------------------------------
I attach the input
Thanks

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```