[Pw_forum] convergence NOT achieved, stopping(additional information)

[Paolo Giannozzi]

On Wednesday 24 November 2004 09:41, Mahmoud Payami wrote:

> [...] I am not doing a metal slab calculation ( for example Al001).

from the manual:
--
Self-consistency is slow or does not converge.

[...] If the highest occupied and lowest unoccupied state(s) keep 
exchanging place during self-consistency, forget about reaching 
convergence. A typical sign of such behavior is that the self-consistency
error goes down, down, down, than all of a sudden up again, and so on.
Usually one can solve the problem by adding a few empty bands and a
broadening.
-- 
Paolo Giannozzi             e-mail:  giannozz at nest.sns.it
Scuola Normale Superiore    Phone:   +39/050-509876, Fax:-563513 
Piazza dei Cavalieri 7      I-56126 Pisa, Italy