[DFTB-Plus-User] Can 3ob SKF files be used for non-SCC calculations?

[Bálint Aradi]

Dear Sharma,

> 1. I have reduced the SCC tolerance to 10^-4
> 2. Increased the no.of SCC iterations to 1000
> 3. I have changed the Fermi temperature. (Though this one gave me the
> converged geometries, these geometries are looking like amorphous carbon
> rather than any possessing any lattice structure/ molecule structure. I
> got this spurious structures even with 1K temperature). 

I had a look at your graphene flake. 1 K electronic temperature is
definitely not enough. You have a system with a very high degeneracy
(ca. 10 levels within 0.1 eV around the HOMO). Running your system with
100 K, it converges without any problems. Also, the geometry is fine,
although it takes quite a long, at the end nothing spectacular happens,
your flake almost stays as it is.

  Best regards,

  Bálint


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


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