[Pw_forum] pbe with norm conserving pp convergence problem

[Paolo Giannozzi]

On Sep 10, 2012, at 16:35 , Peng Chen wrote:

> I tried to calculate an insulator Ni3V2O3 using pbe norm conserving  
> pp from pslibrary. But the energy related with ecutwfc is not  
> converged. It reaches minimum at ecutwfc=80 Ry. But when I fix  
> ecutrho=320 Ry and increase  ecutwfc, it starts to decrease  
> monotonically. I am not sure if the system reaches the convergence  
> at ecutwfc=80 Ry.
> (smearing=mv, Degauss=0.01 Ry and kpoints = 4 4 3)

if it is an insulator, why are you using smearing? Apart from this:
with norm-conserving PP, ecutwfc is the only parameter defining
the basis set. You should not set ecutrho.

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