Hi, thank you for your reply On Tue, 15 Apr 2008, Vasilii Artyukhov wrote:
2008/4/15, Marcel Mohr <[EMAIL PROTECTED]>: The smaller energyshift, should in principle be better, and results in larger basis size.That's not true. It only has to be better for an isolated atom, who knows what would happen in condensed phase. However, you could use the variational principle: whichever basis gives you the lowest energy for a given configuration makes the best approximation to the ideal KS solution (for a given configuration, again).
Then I get nearly linear behaviour PAOshift vs. Total energy, with 5 meV PAO shift gives lowest energy (for my range 5 tp 100 meV).
The behavior you describe is quite consistent with LDA.
Do you mean by that, the fact, that a larger basis gives larger lattice constant?
Hope this helps,
It did Marcel
