[Pw_forum] Charge is wrong : smearing is needed

[Ari P Seitsonen]

Dear Efi Dwi Indari,

   Please try providing some value for 'degauss':

    +--------------------------------------------------------------------
    Variable:       degauss

    Type:           REAL
    Default:        0.D0 Ry
    Description:    value of the gaussian spreading (Ry) for brillouin-zone
                    integration in metals.
    +--------------------------------------------------------------------

In addition you indeed seem to have an odd number of electrons, thus maybe 
you want to specify the total charge of your system, or a spin 
polarisation. Well, it depends on what you want to simulate.

     Greetings from Montrouge,

        apsi

-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-=*=-
   Ari Paavo Seitsonen / Ari.P.Seitsonen at iki.fi / http://www.iki.fi/~apsi/
   Ecole Normale Supérieure (ENS), Département de Chimie, Paris
   Mobile (F) : +33 789 37 24 25    (CH) : +41 79 71 90 935


On Sat, 24 Oct 2015, efi dwi indari wrote:

> Dear all,
> 
> I have a system of CH3NH3PbI3 and I'd like to calculate its electronic
> structure. The first idea is to define the optimum lattice parameter of the
> organic molecules to have no interaction among them. In the whole structure
> of CH3NH3PbI3, the organic molecule is located at the center of the crystal.
> Thus, for first trial, I positioned the organic molecule at the center of
> the molecule and defined ibrav=1 for the molecule as suggested by tools menu
> in x-crysden.
> 
> Even so, I am more confident to put the organic molecule at (0,0,0)
> coordinate if I want to set ibrav=1. To ensure that, I calculated those two
> kinds of atomic positions.
> 
> However, from both calculation, I got the same error messages:
> 
> charge is wrong; smearing is needed.
> 
> From the system that I am assessing, the CH3NH3 has +1 charge. That is why,
> I think, QE thinks that the system is a metal. Since I didn't find any
> reference about the smearing type, I tried all smearing types provided but I
> got the same error.
> 
> Below attached are the input and output file (MA_231015a.scf.in (and out)
> are for the centered organic molecule, and MA_241015b.scf.in (and out) are
> for the one positioned at (0,0,0) coordinates.
> 
> Thank you in advance.
> 
> Best Regards,
> 
> Efi Dwi Indari
> Institut Teknologi Bandung
> 
>