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["Matteo Giantomassi" <Matteo.Giantomassi@uclouvain.be>]

>
>
>
>      I was trying to do a band structure calculation taking GW
>        correction into account. I found the example which is given
>        without GW approxiamtion. I was wondering if anyone know how  to
>        find band structure taking GW into account. What is best way
>        to do ?
> --
> Laxmidhar Senapati
> Code 6390
> Center for Computational Materials Science
> Naval Research Laboratory
> 4555 Overlook Ave, S.W
> Washington DC 20375-5340
> Ph: 614-795-4236

 Dear Laxmidhar,

 There are two useful tutorials showing how to
 perform GW calculations with Abinit.
 You might have a look at the following two links:

 http://www.abinit.org/Infos_v5.4/tutorial/lesson_gw1.htm
 http://www.abinit.org/Infos_v5.4/tutorial/lesson_gw2.htm

 I have to warn you, however, that performing a band structure
 calculation with GW is not as straightforward as a standard
 Kohn-sham calculation.

 First of all, unlike a KS band structure calculation,
 one cannot evaluate the GW corrections at arbitrary k-points
 in the Brillouin zone.

 The quasiparticle energies, indeed, can be calculated only for
 the irreducible k-points included in the so-called KSS file
 (for more details on the meaning and content of the KSS file, please,
 consult the tutorial).

 To obtain a full plot of the GW band dispersion along high-symmetry
directions,
 one usually evaluates the GW corrections for a set of irreducible points
covering
 the considered k-path, and interpolates these value for the k-points that
are not
 explicitly included.

 Hope this helps,

 Best Regards
 Matteo Giantomassi