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Problem with IBZKPT and HSE?

Posted: Thu Sep 05, 2013 3:18 pm
by ecoulter
I am having a strange problem:

(Using vasp.5.3.3)

When running an HSE calculation, starting from GGA wave-functions.

If I run using the automatic k-point generation scheme, everything is fine.
However, if I take the IBZKPT file generated from the GGA run, and use it to start the HSE calculation, with the ONLY difference being that I copy the IBZKPT onto the KPOINTS file, I get a warning about the k-point mesh being non-commensurate with the symmetry of the lattice. (If I use automatic generation, the IBZKPT file generated is exactly the same between the GGA and HSE calculations.)

I am already using a gamma centred mesh. It does not make sense that the output of the k-point generation routine is not usable as input.

Turning ISYM = 0 does nothing. Any suggestions?

This is reproducible on all of the systems I have tried - including bulk Si.
I include some simple input files below that will produce the above behaviour.

**************************
HSE INCAR:
**************************
SYSTEM = bulk Si Calculation

GGA = PE

ISTART = 1
NBANDS = 24

ISMEAR = -5

#comment these lines for the GGA INCAR
LHFCALC = .TRUE.
AEXX = 0.25
AGGAX = 0.75
HFSCREEN = 0.2
PRECFOCK = N
**************************
KPOINTS:

**************************
Automatic mesh
0 ! number of k-points = 0 ->automatic generation scheme
Gamma ! fully automatic: MP-set
6 6 6 ! 8x8x8
**************************
POSCAR
**************************
Silicon Test
1.00000
0.000000 2.715500 2.715500
2.715500 0.000000 2.715500
2.715500 2.715500 0.000000
Si
2
Selective Dynamics
Direct
0.12500 0.12500 0.12500 F F F
0.87500 0.87500 0.87500 F F F

Re: Problem with IBZKPT and HSE?

Posted: Tue Sep 10, 2024 2:31 pm
by support_vasp

Hi,

We're sorry that we didn’t answer your question. This does not live up to the quality of support that we aim to provide. The team has since expanded. If we can still help with your problem, please ask again in a new post, linking to this one, and we will answer as quickly as possible.

Best wishes,

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