[Pw_forum] Bonding Energy

[FELIPE VALENCIA]

> 1. You should not use only \Gamma point for small
> systems (where number of atoms <10). Rather you have
> to use integration via Monkhorst-Pack k-points which
> are generated automatically if you enter:
> 
> K_POINTS{automatic}
> 10 10 10 
> 0 0 0 
> 
> which means that k-points will be generated according
> to Monkhorst-Pack schem,  each direction of reciprocal
> basis vectors is divided by 10 and there is no shift
> of  origin of k-vectors.
> 

Concernig this point I disagree with Eyvaz, It is true that in your
actual input files you are dealing with  small systes, but if your final
goal is to study  molecular systems, you are going to increase the lattice
parameter... the real system has no peridicity (i.e. an infinite lattice
parameter) and the reciprocal space reduces then to the gamma point, so
that Gamma point seems to me the logical  for
molecules...

Felipe