[Pw_forum] lattice parameter in 'vc-relax' mode doesn't change

[Paolo Giannozzi]

On Sun, 2014-08-17 at 02:33 +0000, Sokseiha Muy wrote:

> I'm using QE to study the properties of BaF2 which is a cubic
> material. I notice that when I used the option 'vc-relax' to optimized
> my structure, in the output the volume of the unit cell change as
> expected but the lattice parameter is the same for every step. 

the lattice parameter is set to its starting value. It is the length
of the primitive vectors that changes. Look for the primitive vectors
in the output: they are reprinted in various places and formats.

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