The stress calculation with hybrid functionals is actually implemented,
but there are still some mysterious problems. See:
https://gitlab.com/QEF/q-e/-/issues/204
Paolo
On 6/14/23 15:46, Giuseppe Mattioli wrote:
Dear Salma
I don't know how outdated it is, but there is a README in the directory
of the EXX examples
/path_to_QE_7.2/PW/examples/EXX_example
reporting this:
WHAT PROPERTIES CAN I COMPUTE ?
Energy and forces (thanks to Hellmann-Feynman theorem forces do not
require extra calculations). In principle also stresses but the
corresponding formulas have not yet been coded. <-------!!!!!!!
So structural optimization is OK if the cell shape is kept fixed.
HTH
Giuseppe
Quoting NAIMI SALMA <[email protected]>:
Dear all,
I'm doing a vc-relax for my material with hybrid functionals and ONCV
pseudopotentials.
When the job is done I can't find the optimized final coordinates and
lattice parameter in the output file , also I noticed that the final
pressure is positive and not close to zero, as bellow:
Computing stress (Cartesian axis) and pressure
total stress (Ry/bohr**3) (kbar)
P= 106.49
0.00072391 -0.00000000 0.00000000 106.49 -0.00
0.00
-0.00000000 0.00072391 0.00000000 -0.00 106.49
0.00
-0.00000000 -0.00000000 0.00072391 -0.00 -0.00
106.49
I repeated the calculation so many times by modifying some input
variables but the same problems always occur for PBE0 and HSE as well.
Before the last lines in the output file I find this:
...
Input lattice vectors:
-0.50342437 0.00000000 0.50342437
0.00000000 0.50342437 0.50342437
-0.50342437 0.50342437 0.00000000
New lattice vectors in INITIAL alat:
-0.50342437 0.00000000 0.50342437
0.00000000 0.50342437 0.50342437
-0.50342437 0.50342437 0.00000000
New lattice vectors in NEW alat (for information only):
-0.50000000 0.00000000 0.50000000
0.00000000 0.50000000 0.50000000
-0.50000000 0.50000000 0.00000000
Discrepancy in bohr = 0.000000 0.000000 0.000000
The maximum number of steps has been reached.
End of BFGS Geometry Optimization
new unit-cell volume = 382.92325 a.u.^3 ( 56.74337 Ang^3 )
density = 5.57333 g/cm^3
CELL_PARAMETERS (alat= 11.44879234)
-0.503424371 0.000000000 0.503424371
0.000000000 0.503424371 0.503424371
-0.503424371 0.503424371 0.000000000
ATOMIC_POSITIONS (crystal)
....
Where this problem is coming from please and how can I fix it?
I attached my input file
------------------------------------------------------------
Salma NAIMI
PhD student - Mohamed 5 University-Rabat
GIUSEPPE MATTIOLI
CNR - ISTITUTO DI STRUTTURA DELLA MATERIA
Via Salaria Km 29,300 - C.P. 10
I-00015 - Monterotondo Scalo (RM)
Mob (*preferred*) +39 373 7305625
Tel + 39 06 90672342 - Fax +39 06 90672316
E-mail: <[email protected]>
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Univ. Udine, via delle Scienze 208, 33100 Udine, Italy
Phone +39-0432-558216, fax +39-0432-558222
_______________________________________________
The Quantum ESPRESSO community stands by the Ukrainian
people and expresses its concerns about the devastating
effects that the Russian military offensive has on their
country and on the free and peaceful scientific, cultural,
and economic cooperation amongst peoples
_______________________________________________
Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
users mailing list [email protected]
https://lists.quantum-espresso.org/mailman/listinfo/users
