[Pw_forum] Hybrid functional pressure

[Davide Ceresoli]

Dear Sam,
     I hope I have implemented correctly the formula found in:
Phys. Rev. B 73, 125120 (2006). As suggested by Stefano Baroni
I test it by applying finite deformations to an fcc-silicon cell.

I recall that it worked well for the diagonal components of the
stress, although it converges extremely slowly with respect to
q-points (not k-points, but nq1, nq2, nq3). For the off-diagonal
components (i.e. shear modulus), I couldn't achieve convergence.

The answer to your question is: we need more testing. Maybe you
can help by testing the two approaches (the formula and the finite
deformations) on your system and then let us know.

Best,
     Davide


On 01/-10/-28163 08:59 PM, Azadi, Sam wrote:
> Dear QE users,
>
> As it's written in README file of EXX_examples directory, corresponding formula of stress calculation
> using hybrid functionals have not yet been coded in quantum espresso.
> But by choosing "tstress =true." in scf input file, there is a value for stress in scf output file.
> My question is, is it reliable ?
>
> Yours
> S.A
>
>

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