[DFTB-Plus-User] Electronic temperature

[Reinaldo Pis Diez]

Dear folks,

I'm very used to use some electronic temperature to speed up scf 
convergence during dftb calculations. It works really good. 
Moreover, I can restart those calculations diminishing the 
electronic temperature up to integer orbital occupations are obtained.

However, a new system under study is becoming really hard to 
converge. I'm able to achieve convergence with small electronic 
temperatures but at the cost of having some non-integer occupation 
numbers. If the temperature is decreased a little, then no 
convergence is achieved at all. Thus, my question is: what limiting 
values are accepted for non-integer occupation numbers when electron 
smearing or electron temperature is used for scf? That is, is a 
distribution like 0.70-0.30, for example, acceptable or not?

Regards,

Reinaldo