[QE-users] Eigenvalues for vc relax not converging
priyashrivastava16 at gmail.com
Fri May 11 08:35:18 CEST 2018
> >Dear Priya,
> >Some quick comments:
> > - Are you sure that the ecutwfc = 20 Ry is sufficient? The 40 Ry that
> >mention sounds much more realistic, if not even higher value would be
> >needed; the calculation of the stress tensor ("vc-relax") requires a
> >stricter convergence with respect to the cut-off energy/basis set than
> >example total energy as the former is a (second) derivative of the
> >and the basis set would in principle be a function of the lattice
> >constant, so better be well converged in the basis set
> Yes Sir, I have changed it to 40 Ry.
> - Since you have an FCC lattice you could easily calculate the total
> >energy of the ("relax"'ed) system as a function of the lattice parametre
> >and check if you converge toward the same value as the 'vc-relax'
Thankyou for the suggestion but if i understand correctly did you mean
that i run 'relax' calculation instead of vc-relax? and Also how does FCC
lattice makes a difference to
calculation of total energy (did you mean symmetry-wise?)
> - Do I understand you correctly that you can reach convergence in the
> self-consistent loop, but in the subsequent loops the electronic structure
> does not convergence (as the D3 does not affect the electronic structure
> explicitly, only via the modified lattice constant)
Yeah it seems so to me. Please see the ouput (see link)---->.
- Your value for smearing is quite small; you could at least temporarily
try to increase it
I have made it 0.01 (job is running). i will send the ouput once it is
> - What is the lowest value of convergence that you reach in, say 100
> Please see o/p (see link) for better insight. Thank you Dr. Apsi for
your kind comments.
-------------- next part --------------
An HTML attachment was scrubbed...
More information about the users