[DFTB-Plus-User] SCC unconvergence problem

Vinay Hegde vinayhegde at jncasr.ac.in
Mon Dec 3 21:38:46 CET 2012


Dear Mahesh,

Please look at the trend in the total energies in the standard output.
Does it look like it is converging (is the SCC error reducing
systematically)? If yes, then you would do well to increase the
MaxSCCIterations. If, instead, your structure appears to be stuck in a
local minimum, you could try one of the following:
1. Use some finite temperature to speed up convergence (be aware of
the consequences though)
2. Use a few non-SCC iterations initially
3. Use ConvergentForcesOnly = No
The last two options being useful in case you have some non-physical
geometries to begin with.

I'd prefer to have a look at your standard output before commenting
further though.

Hope this helps,
Vinay

--

Vinay Ishwar Hegde
Graduate Student
Theoretical Sciences Unit (TSU)
Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR)
Jakkur, Bangalore 560 064
Email: vinayhegde at jncasr.ac.in
Phone: +91-96639-92336


More information about the DFTB-Plus-User mailing list