[Pw_forum] 1 of 17 vc-relax lattice constance optimzition

[Paolo Giannozzi]

There isn't much to explain: nobody has ever written down and
implemented  the formula for stress in the case of meta-GGA. In QE
meta-GGA is implemented (sort of) only for norm-conserving
pseudopotential, so there is no need (bot that I know) to store the
kinetic energy density in the PP file

Paolo

On Wed, Jun 28, 2017 at 4:34 AM, Hong Tang <tanghong992 at gmail.com> wrote:
> Dear Paolo:
>
>
>
> Thank you so much for helping.
>
> I tried grep -n “stress” Si.rx.out
>
> What I got is below:
>
> [hongtang at login4 results]$ grep -n "stress" Si.rx.out
>
> 1797:     entering subroutine stress ...
>
> 1799:     Message from routine stress:
>
> 1800:     Meta-GGA and stress not implemented
>
> 3128:     entering subroutine stress ...
>
> 3130:     Message from routine stress:
>
> 3131:     Meta-GGA and stress not implemented
>
> 4442:     entering subroutine stress ...
>
> 4444:     Message from routine stress:
>
> 4445:     Meta-GGA and stress not implemented
>
> 5764:     entering subroutine stress ...
>
> 5766:     Message from routine stress:
>
> 5767:     Meta-GGA and stress not implemented
>
> 7555:     entering subroutine stress ...
>
> 7557:     Message from routine stress:
>
> 7558:     Meta-GGA and stress not implemented
>
>
>
> It shows MetaGGA and stress not implemented.  Maybe this is the problem
> there.
>
> I want to do structure optimization with metagga functional (TPSS here).  In
> VASP, I know the pseudo potentials (pps) of the elements should have
> “kinetic energy density”.  In quantum espresso, I don’t know what should be
> in the pps. The pps I chose for Si is for tpss, as you can see from the
> input file.
>
>
>
> Please explain to me a bit more clear how to fix the problem. I appreciate
> your helps very much.
>
>
>
> Hong Tang
>
> Temple University
>
> Philadelphia, PA 19122 US
>
>
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-- 
Paolo Giannozzi, Dip. Scienze Matematiche Informatiche e Fisiche,
Univ. Udine, via delle Scienze 208, 33100 Udine, Italy
Phone +39-0432-558216, fax +39-0432-558222