[Pw_forum] Energy convergence in Cobalt

[Paolo Giannozzi]

On Friday 03 March 2006 16:01, Conor Hogan wrote:

> I noted that the total energy does not decrease if the kinetic energy
> cut-off is increased, which is not what I expected (in fact it increases!)

I think this was already discussed in the forum, but I cannot find the
reference. With ultrasoft PPs you are not guaranteed that the energy
decreases with increasing cutoff, because the augmentation charge
density is not exact but truncated (to cutoff "ecutrho")

Paolo
-- 
Paolo Giannozzi             e-mail:  giannozz at nest.sns.it
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