[CP2K-user] [CP2K:18220] MOF cell opt with KEEP_SYMMETRY FALSE

Corrado Bacchiocchi bacchio at gmail.com
Tue Dec 20 08:52:11 UTC 2022

Dear Colleagues,
I ask you to kindly share your experience about the following question.

We have performed on our MOF structure the "Converge CUTOFF and REL_CUTOFF" 
procedure, as described in the very helpful page:


and found that, with  NGRIDS 4, to reach a 1.E-7 difference with respect to 
the limiting value of the energy, the minimum settings are:
      CUTOFF 1800
      REL_CUTOFF 80

We have then successfully performed CELL_OPT on a 2x2x2 supercell of our 
When we use this optimized structure for a subsequent CELL_OPT with 
KEEP_SYMMETRY FALSE the BFGS algorithm is not able to further decrease the 
energy. The structure remains essentially unmodified across hundreds of 
steps and the optimization does not complete.
I attach the input file and the guess structure and I kindly ask the 
- is it essential, for any publication quality structure, that KEEP_SYMMETRY 
is FALSE or is it acceptable to have this constraint in place?
- more in general, for any subsequent calculation, e.g. interaction of 
small molecules on the surface of the MOF, Nudged Elastic Band energy path 
investigations, etc., is it possible/acceptable to KEEP_SYMMETRY TRUE?

Thank you very much for your kind help
Have a nice Holiday Season!

You received this message because you are subscribed to the Google Groups "cp2k" group.
To unsubscribe from this group and stop receiving emails from it, send an email to cp2k+unsubscribe at googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/cp2k/14f06834-79c7-4ac8-922c-d1d6f008d27fn%40googlegroups.com.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.cp2k.org/archives/cp2k-user/attachments/20221220/2f318c1b/attachment-0001.htm>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: cp2k.inp
Type: chemical/x-gamess-input
Size: 2009 bytes
Desc: not available
URL: <https://lists.cp2k.org/archives/cp2k-user/attachments/20221220/2f318c1b/attachment-0001.inp>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: guess.xyz
Type: chemical/x-xyz
Size: 13371 bytes
Desc: not available
URL: <https://lists.cp2k.org/archives/cp2k-user/attachments/20221220/2f318c1b/attachment-0001.xyz>

More information about the CP2K-user mailing list