[Pw_forum] rhoup > 1 issue

[Paolo Giannozzi]

On Wednesday 02 March 2005 15:49, B.T. Hope wrote:

> A relax calculation on a cobalt nano-wire with spin turned on is not
> converging in one of the scf calculation steps. Reducing the mixing beta
> and increasing the convergence threshold have no effect.
>
> In the output it tells me that a very large number of points have rhoup AND
> rhodown less than zero. Is this the soucre of the problem? Indeed does this
> matter?

it depends. A very small negative charge in empty space does not 
matter. These messages might however signal that the cutoff for the 
charge density (or maybe also for the wavefunctions) is too small.
Try to increase it.

Paolo

-- 
Paolo Giannozzi             e-mail:  giannozz at nest.sns.it
Scuola Normale Superiore    Phone:   +39/050-509876, Fax:-563513 
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