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[matthieu verstraete <matthieu.jean.verstraete@gmail.com>]

CASTEP should be calculating the EF in the same way. What do you mean that it is not good enough? The non-SCF GS is a good way of getting a more precise EF, and I would also decrease tsmear (also make sure that this is identical btw abinit and CASTEP - it is the most influential factor).

Matthieu

On Sat, Feb 14, 2009 at 6:46 PM, <6671011@163.com> wrote:

Dear Matthieu,

Thanks for explanation.

The problem I met is that the EF in the SCF-GS is not accurate enough for the
BS. So, according to your reply, the only reasonable solution is improving the
SCF-GS calculation?  Or maybe I could add a non-SCF GS calculation between the
SCF-GS and the BS calculation?

p.s. I am dealing with 1D system. And there is no such problem when I work with
CASTEP at almost the same accuracy level.


Sincerely,
Guangfu Luo


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The Fermi energy should be taken from the full GS calculation, not the BS,
whose k-points are not weighted and distributed evenly throughout the Brillouin
Zone. Also, there is no need to calculate the Fermi energy as the density is
already fixed. This is why EF is not output for the non scf case.

Matthieu


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On Sat, Feb 14, 2009 at 1:31 AM, <6671011@163.com> wrote:

Dear Friends,

  I hope to obtain the Fermi Energy in the Band Structure calculation.
However, Abinit does not export it in the default situation, though it does
that in the GS calculation.

 Is it possible to get it easily by setting some parameter? (I can get the
Fermi Energy according to its definition in the Band Structure, but probably
Abinit has this function already.)


Thanks a lot.

Sincerely,
Guangfu Luo

-- 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Dr. Matthieu Verstraete

European Theoretical Spectroscopy Facility (ETSF) 
Dpto. Fisica de Materiales, 
U. del Pais Vasco,            
Centro Joxe Mari Korta, Av. de Tolosa, 72,   Phone: +34-943018393
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Mail : matthieu.jean.verstraete@gmail.com
http://www-users.york.ac.uk/~mjv500