[Pw_forum] negatice dexx error in scf calculation with hybrid functional GAUPBE by incorporating SOC

[VineetKumar Pandey]

Dear users,
                  I am doing an SCF calculation for monolayer PbI2 by means
of exchange function gaupbe with SOC(spin-orbit coupling). The kmesh and
qmesh used for this calculation are 15 x 15 x1 and 3x3x1, respectively.
Just after it does the first step to refine exchange calculation it gives
me an error "dexx is negative". However, I was able to run the same SCF
calculation using the same kmesh but with different qmesh of size 1x1x1. I
again get the same error when calculation is done with the qmesh of 1x1x1
and on full BZ kpoints of 15x15x1. I have also tried for a range of
ecutfock from 360 to 600 Ry but I still end up getting the same error.

Can you please help me to understand and rectify this error?

Please find attached input and output files in this email.
Best Wishes
Vineet Kumar Pandey
IISER PUNE, INDIA
PINCODE-411008

Phone: +91 8853094275
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