[Pw_forum] wave function cutoff range for pseudopotentials

[Tan Hengxin]

Dear Bhushan,

The best cutoff energy should be the well tested one, which satisfies your
requests. Generally, I would use the largest cutoff energy for the
wavefunction in the pseudopotential files as the start point.

I don't think there is a very clear boundary line between uspp and ncpp,
and, the energy range of ncpp can also be very large. Generally, ncpp would
be more expensive than uspp.
What kind of pseudopotential you use should depend on your request again.
Nobody requires that you must us this or that kind of pseudopotential. The
one that gives the real physics is the best one.

Best,
Tan
THU

On Thu, Aug 24, 2017 at 7:33 PM, B S Bhushan <ecebhushan at gmail.com> wrote:

> Dear Experts,
>
> I'm new to Quantum Espresso. As a starter, I have got few questions while
> performing simulations.
>
> (1) In what range the wavefunction cutoff range for Ultrasoft,
> normconserving and PAW pseudopotentials lies?
> I read on google that, for ultrasoft pseudopotentials the wavefunction
> cutoff ranges from 20-50 Ry, while for norm-conserving pseudopotentials it
> is from 60-100 Ry. Is it correct ?. or the norm-conserving pseudopotentials
> can also have range starting from 20-100 Ry ?.
>
> (2) I am simulating defects in graphene. Which pseudopotential should I
> prefer for graphene, Ultrasoft or Norm-conserving or PAW ?
>
>
> I am really thankful for your valuable time and knowledge.
>
> Thank you.
>
>
> Sincerely,
> B. S. Bhushan,
> CNT Laboratory,
> ABV - Indian Institute of Information Technology and Management,
> Gwalior, India.
>
>
> _______________________________________________
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>



-- 

Tan Hengxin
Department of physics, THU.
Beijing 100084, China
Office: B403,New Science Building
E-mail:t <E-mail%3Athx13 at mails.tsinghua.edu.cn>anhx90 at gmail.com
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.quantum-espresso.org/pipermail/users/attachments/20170824/64ae8ea9/attachment.html>