SCC can not be converged.

[zq84229]

Recently, I have made an interface of HOTBIT parameterization module to DFTBplus.
In order to obtain Rep, a skf file without Rep would be prepared for DFTBplus after Hamilton and overlap calculations. However, I found that, the SCC calculations using the skf files were always not converged.
Now, I am focusing on the parameters about Boron. The problems have occurred in B-H and B-B.
When I set electron temperature to 0.005 K, the problem would be disappeared.
I do not know which parameter can be used to solve the problem during the parameterization.
Could you give me some advice ? Thank you very much.

[ajjackson]

Are the SCC calculations which are failing being performed in Hotbit or DFTB+?

[zq84229]

@ajjackson, the SCC calculations are performed in DFTB+. A skf file contains H and S obtained from Hotbit parameterization, but not the repulsive potential.

[ajjackson]

Have you been succesful in running DFTB+ calculations with no repulsive potential by disabling SCC? Maybe it is necessary to get a rough repulsive potential without SCC then optimize with SCC?

[zq84229]

I'll’ try at once.Thanks for your reminding.