Hi Thierry,
I don't know if it's only for the system I am working on or general but:

I found in the last version of PW, 5.4, the hybrid are much more faster so you 
could upgrade it
Consider of using HSE06 instead of PBE0 

Cheers
Davide
________________________________________

Message: 1
Date: Thu, 23 Jun 2016 12:32:06 +0000
From: Thierry Clette <[email protected]>
Subject: Re: [Pw_forum] PBE0 Hybrid functional SCF doesn't complete
To: PWSCF Forum <[email protected]>
Message-ID:
        
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So that is how I did it wrong


Thanks for the tips


Have great day


Thierry Clette

________________________________
De : [email protected] <[email protected]> de la part de 
stefano de gironcoli <[email protected]>
Envoy? : jeudi 23 juin 2016 10:33:17
? : PWSCF Forum
Objet : Re: [Pw_forum] PBE0 Hybrid functional SCF doesn't complete

the Hybrid calculations are VERY expensive.
in solids the expensive Fock step has an inner summation on k-point that makes 
it QUADRATIC in the grid dimension used (20*20*20)^2, in your case.
No wonder it does not complete

Things I would do:
- reduce the cutoff to the minimum.
- consider using a NC pseudopential.
- please no gaussian smearing. use 'mv' or 'mp'.
- use larger smearing => smaller k-points set
- read, understand and test the nqx1,nqx2,nqx3 input options
- look for a big machine and use band parallelization to distribute work load.

HTH

stefano

On 22/06/2016 12:22, Thierry Clette wrote:

Hello,


I'm a student at the University of Brussels. I use QE 5.2.1.

I'm trying to do a SCF calculation of bulk black Phosphorus, a semiconductor 
with a small gap. PBE0 seems to be the right method for this, so I use a 
normcon PBE pseudopotential from the QE site with the option "input-DFT=PBE0". 
The inputs and outputs are attached.

As you can see in the output, the calculation in itself seems to work, but the 
process doesn't seem to finish. It seems it can't write to the save. Usually 
the process never finishes and is killed by time out. In some cases, it is 
killed for using too much RAM (after the calculation is complete, very 
strange). Anyway, as it doesn't finish, I can't do band calculations.

Are some of my parameters wrong ?


Thanks in advance


Thierry Clette
________________________________


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