[Pw_forum] R: Re: metallic BP?

[Paolo Giannozzi]

On Dec 4, 2011, at 12:22 , giacsport at libero.it wrote:

> I only wonder if in this case both people working at OCSA
> and at Tokyo University should specify ibrav=2

they should

> or ibrav=4 (rhombohedral, since angles are 60 deg)...   :)

they shouldn't, because ibrav=4 means "hexagonal lattice":
axis "a" along x, axis "b" at 120 degree with axis "a", axis
"c" orthogonal to the plane formed by axis "a" and "b", as
explained in much detail in the documentation.

If you really plan to apply to a position at OCSA, you may
prove your ability to complicate simple things by choosing
ibrav=5 or (recent QE versions only) ibrav=-5: this is a
trigonal (rhombohedral) lattice, with 3-fold axis around <001>
(ibrav=5) or <111> (ibrav=-5)

P.
---
Paolo Giannozzi, Dept of Chemistry&Physics&Environment,
Univ. Udine, via delle Scienze 208, 33100 Udine, Italy
Phone +39-0432-558216, fax +39-0432-558222