[QE-users] 2D CODE WILL NOT WORK, 2D MATERIAL NOT IN X-Y PLANE

[Dr. Thomas Brumme]

Dear  Julien,

Maybe it's because your cell vectors 1 and 2 are pointing
slightly in the z direction? I don't know but I think this
could be a problem. If it is just a rotation of the whole
cell you could try rotating it back... Otherwise search the
code for the message and look when it is triggered.

Regards

Thomas

Zitat von Julien Barbaud <julien_barbaud at sjtu.edu.cn>:

> Dear users,
>
>
>
> I am running into a new problem while trying to perform a calculation on a
> 2D slab consisting of 4 unit cells in the z-direction with an additional
> molecule on top of an under-coordinated surface atom.
>
> When I try to run the code (in serial mode just for checking), I get this
> message:
>
> 2D CODE WILL NOT WORK, 2D MATERIAL NOT IN X-Y PLANE!!
>
> 2D CODE WILL NOT WORK, 2D MATERIAL NOT IN X-Y PLANE!!
>
> (repeated twice as shown here)
>
>
>
> I tried to search, but could not find any documentation on this error.
>
>
>
> I thought that this might be due to a vacuum slab too small, but the
> dimension should be ok according to previous calculations on similar
> systems, and increasing the c lattice to very large values constant does not
> solve the problem.
>
> I made sure that the slab+molecule were centered around 0 in the z-direction
> as I have been told on this list that this was important for the 2D code not
> to cutoff some real coulombian interactions. This did not solve the problem.
> I also tried to wrap all atoms in the cell, but this did not change anything
> (plus it necessarily meant that the system was not centered around 0
> anymore).
>
>
>
> I do not understand this error message. What does "not in x-y plane" mean
> for this 2D code? What confuses me is that I have been doing several very
> similar calculations, and I never had this problem before. Any suggestion ?
>
>
>
> I will join my input file
>
>
>
> Thanks for reading,
>
> Julien

-- 
Dr. rer. nat. Thomas Brumme
Wilhelm-Ostwald-Institute for Physical and Theoretical Chemistry
Leipzig University
Phillipp-Rosenthal-Strasse 31
04103 Leipzig

Tel:  +49 (0)341 97 36456

email: thomas.brumme at uni-leipzig.de