[DFTB-Plus-User] SCC calculations of Ni cluster is not converged

[Bálint Aradi]

Dear chenghongye,

> I am a new user of DFTB-plus. There are some problems when I perform geometry calculations of Ni cluster. The Ni cluster contains 13 atoms with a face-centered cubic truncated octahedron arrangement. The SCC calculations of Ni cluster is not converged when it reach the max steps , which I set to 10000. Is there anything improper in my dftb_in.hsd file? How can I modify it?

 This is not DFTB related, it is more computational technique. If you
use a system where you expect a lot of levels very close to each others
(metals, metalic surfaces, etc.) you should use some temperature to ease
the convergence. Setting the electronic temperature to 40 K, resolves.
the issue.

  Best regards,

    Bálint
-- 
Dr. Bálint Aradi
Bremen Center for Computational Materials Science, University of Bremen
http://www.bccms.uni-bremen.de/en/~b_aradi


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