[Pw_forum] honeycomb

[Paolo Giannozzi]

On Monday 19 December 2005 15:44, Aritz Leonardo wrote:

> > ATOMIC_POSITIONS (alat)
> > C    0.0   0.000000000   0.0
> > C    0.0   0.577350270   0.0
>
> I think that this line should be changed
>
> > C    0.0   0.000000000   c/(2a) by--> C  0.0  0.577350270 c/(2a)
> > C    0.5   0.288675135   c/(2a)

it seems to me they are the same. In both cases you two layers of 
hexagons, stacked one above the other, displaced in such a way 
that the the two sublattices of the second layer are either above 
one of the sublattices of the first layer, or above the centers of
the hexagons od the first layer.

Paolo

-- 
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