[Pw_forum] adding vacuum

[Jaret Qi]

but that will cost time! 
 


     On Monday, November 16, 2015 9:26 AM, Pascal Boulet <pascal.boulet at univ-amu.fr> wrote:
   

 Hello,
4 angstroms wide seems to be very small for the vacuum. As a rule of thumb you should use at least 2.5 times the thickness of your slab. This is what we observed in the calculations of semiconductor slabs. This has to be tested.
Pascal
Le 16 nov. 2015 à 16:40, Jaret Qi <jaretqi at yahoo.com> a écrit :

Hello all,I am trying to minimize the interaction between my system and its periodic images. To do so, I introduced a layer of vacuum along the z-axis by increasing the lattice vector along the z-axis by 4A. At the same time, I fixed it by using this parameter: cell_dofree='2Dxy',But I have noticed atoms that are close to the vacuum move along the z-axis and vacuum is decreasing, is this wrong or I should use different cell_dofree?note:relaxation still ongoing, not relaxed yet.

JARET,ASU_______________________________________________
Pw_forum mailing list
Pw_forum at pwscf.org
http://pwscf.org/mailman/listinfo/pw_forum

--
Pascal Boulet - MCF HDR, Resp. L1 MPCI - DEPARTEMENT CHIMIEAix-Marseille Université - ST JEROME - Avenue Escadrille Normandie Niemen - 13013 MarseilleTél: +33(0)4 13 55 18 10 - Fax : +33(0)4 13 55 18 50Site : http://allos.up.univ-mrs.fr/pascal - Email : pascal.boulet at univ-amu.frAfin de respecter l'environnement, merci de n'imprimer cet email que si nécessaire.


  
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.quantum-espresso.org/pipermail/users/attachments/20151116/f901748a/attachment.html>