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I've had the same issue a few months ago with QE6.7. I've had to switch to CP2K for this purpose, which is also open source. Note that it's build on a hybrid approach of Gaussian and plane waves basis sets. For the organic systems I simulated, 800+ Ry were
 required with PBE0, Coulomb truncation and long range correction, for an excellent volume and energy convergence.<br>
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Xavier<br>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> users <users-bounces@lists.quantum-espresso.org> on behalf of Paolo Giannozzi <p.giannozzi@gmail.com><br>
<b>Sent:</b> Thursday, October 14, 2021 6:35 AM<br>
<b>To:</b> Quantum ESPRESSO users Forum <users@lists.quantum-espresso.org><br>
<b>Subject:</b> Re: [QE-users] Stress in hybrid functional calculations</font>
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<div dir="ltr">The stress converges _very_ slowly with cutoff. The ultimate test for stress is to compare it with the numerical derivatives of the energy, computed at a _fixed_ number of plane waves. This has been done more than once and I am quite sure that
 the stress is correctly computed.  There are still some problems in variable-cell calculations, though, of unclear origin:
<a href="https://nam04.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgitlab.com%2FQEF%2Fq-e%2F-%2Fissues%2F204&data=04%7C01%7Cxavbdlt%40uic.edu%7C8efb9e51915f481c4af108d98f06e97b%7Ce202cd477a564baa99e3e3b71a7c77dd%7C0%7C0%7C637698082279068798%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000&sdata=EGQceIcEn7KXch8cFnh7jGlsu2IMNzmDHUFI%2BB9lTDs%3D&reserved=0" originalsrc="https://gitlab.com/QEF/q-e/-/issues/204" shash="kQLj7775x5hymmAZSLneqfoe8H44be7V4mwTFada55A08cuVGPwqL/Xtafu2SYfyATo4Mxz3UlnomILMl2ACZl5HZWItTXXD8xRZ7rbom0d0ns8OguOhk+rFRlJQp/t1hsT4ktqDLQRLHuV+dcvbIhlyDV8veea0UMS+d8DNFZ8=">
https://gitlab.com/QEF/q-e/-/issues/204</a>.
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<div>Paolo</div>
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<div dir="ltr" class="x_gmail_attr">On Thu, Oct 14, 2021 at 1:17 PM Audrius Alkauskas <<a href="mailto:audrius.alkauskas@ftmc.lt">audrius.alkauskas@ftmc.lt</a>> wrote:<br>
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Dear all,<br>
<br>
We have started testing the Quantum Espresso implementation of screened <br>
Fock exchange (HSE functional), benchmarking against VASP results (the <br>
input file below).<br>
<br>
As a test case, we took simple bulk diamond. If we calculate the energy <br>
as a function of the lattice constant, the resulting equilibrium lattice <br>
parameter (3.555 A) and bulk modulus are very similar to the results <br>
from VASP, which is nice. However, the calculated stress for the <br>
equilibrium lattice parameter is still large (~30 kBar).  The stress is <br>
linear as a function of the lattice constant and is ~0 for the lattice <br>
constant 3.585 A, yielding an offset of about 0.03 A with respect to <br>
what I assume is the "correct" HSE value. The value of 3.585 A is much <br>
closer to the PBE result.  Are there still some issues when calculating <br>
stresses with hybrids or we do something wrong? Energies seem OK, <br>
stresses not (the error is not huge, but still...)<br>
<br>
If anybody has any insights, I would be happy to get receive them.<br>
<br>
Best,<br>
Audrius<br>
<br>
***<br>
Input<br>
***<br>
<br>
&CONTROL<br>
    calculation      = 'scf'<br>
    title            = 'carbon-cubic-hse-3.556'<br>
    verbosity        = 'high'<br>
    nstep            = 100<br>
    tstress          = .true.<br>
    tprnfor          = .true.<br>
    outdir = '/home/vytautas/HSE/C/relax/3.556'<br>
    etot_conv_thr    = 1e-06<br>
    forc_conv_thr    = 1e-05<br>
    pseudo_dir       = '.'<br>
/<br>
&SYSTEM<br>
    ibrav            = 1<br>
    celldm           = 6.719866103476117<br>
    nat              = 8<br>
    ntyp             = 1<br>
    nbnd             = 24<br>
    ecutwfc          = 100<br>
    ecutrho          = 400<br>
    ecutfock         = 400<br>
    input_dft        = 'hse'<br>
    exxdiv_treatment = 'gygi-baldereschi'<br>
    x_gamma_extrapolation = .true.<br>
    nqx1             = 4<br>
    nqx2             = 4<br>
    nqx3             = 4<br>
    celldm(1)        = 6.719866131544066<br>
/<br>
&ELECTRONS<br>
    electron_maxstep = 300<br>
    conv_thr         = 1e-08<br>
/<br>
&IONS<br>
/<br>
&CELL<br>
/<br>
<br>
ATOMIC_SPECIES<br>
C 12.011 C.upf<br>
<br>
K_POINTS automatic<br>
4 4 4  0 0 0<br>
<br>
ATOMIC_POSITIONS angstrom<br>
C 0.0000000000 0.0000000000 0.0000000000<br>
C 1.7780000000 1.7780000000 0.0000000000<br>
C 0.8890000000 0.8890000000 0.8890000000<br>
C 2.6670000000 2.6670000000 0.8890000000<br>
C 0.0000000000 1.7780000000 1.7780000000<br>
C 1.7780000000 0.0000000000 1.7780000000<br>
C 0.8890000000 2.6670000000 2.6670000000<br>
C 2.6670000000 0.8890000000 2.6670000000<br>
<br>
<br>
<br>
-- <br>
Audrius Alkauskas<br>
Center for Physical Sciences and Technology (FTMC)<br>
Vilnius, Lithuania<br>
<br>
email: <a href="mailto:audrius.alkauskas@ftmc.lt" target="_blank">audrius.alkauskas@ftmc.lt</a><br>
phone: +370 612 22281<br>
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<br>
_______________________________________________<br>
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-- <br>
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<div>Paolo Giannozzi, Dip. Scienze Matematiche Informatiche e Fisiche,<br>
Univ. Udine, via delle Scienze 206, 33100 Udine, Italy<br>
Phone +39-0432-558216, fax +39-0432-558222<br>
<br>
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