[Q-e-developers] Reporting bug in QE ph.x

[Nathalie VAST]

Dear Paolo

This is an 8-month (partial time) work. May be Giuliana can commit, if allowed

Best regards
Nathalie

> Le 10 avr. 2017 à 16:41, Paolo Giannozzi <p.giannozzi at gmail.com> a écrit :
> 
> If nobody has any better idea, I'll commit reset_grid modified as in
> the message below
> 
> Paolo
> 
> On Fri, Apr 7, 2017 at 10:07 PM, Paolo Giannozzi <p.giannozzi at gmail.com> wrote:
>> Thank you Giuliana. While waiting for better solutions, the best way
>> to communicate problems and proposed solutions is via the
>> q-e-developers mailing list (CC:).
>> 
>> It is likely sufficient to modify the function reset_grid as follows:
>> 
>>       reset_grid = (nk1_*nk2_*nk3_ > 0)
>>       IF ( .NOT. reset_grid ) RETURN
>>       nk1 = nk1_
>>       nk2 = nk2_
>>       nk3 = nk3_
>>       k1 = k1_
>>       k2 = k2_
>>       k3 = k3_
>> 
>> but given the complexity of linear-response codes I cannot rule out
>> unexpected side effects
>> 
>> Paolo
>> 
>> 
>> On Fri, Apr 7, 2017 at 7:38 PM, Giuliana Barbarino
>> <giuliana.barbarino at polytechnique.edu> wrote:
>>> Dear Paolo Giannozzi,
>>> I am Giuliana Barbarino and I am a Postdoc at the Laboratoire des Solides
>>> Irradies in Ecole Polytechnique. My supervisor is Nathalie Vast and I work
>>> with Jelena Sjakste on a project about electron-phonon coupling.  Nathalie
>>> suggested me to write to you because I found a problem on PH code. It
>>> regards the possibility to reset a new grid of k-points inside Phonon.
>>> 
>>> If the self consistent calculation is performed with an automatically
>>> generated Monkhorst-Pack grid (nk1,nk2,nk3) and with the grid offset
>>> k1=1,k2=1,k3=1 and in the phonon input it is specified a new k-points grid
>>> to run the pw non-self consistent calculation without offset
>>> k1=0,k2=0,k3=0, the phonon code doesn't change the grid and it performs
>>> anyway the calculation with (nk1,nk2,nk3,1,1,1).
>>> This also if any k1,k2,k3 is specified by input, even if the default
>>> values of k1,k2,k3 variables should be 0.
>>> 
>>> The reset_grid function, called in phq_readin and defined in the
>>> subroutine  start_k of PW code, resets the automatic grid to new values
>>> only if these are > 0. The (nk1,nk2,nk3,k1,k2,k2) defined in start_k are
>>> then used to setup the non-self consistent calculation.
>>> 
>>> This bug is not important in the case of a simple phonon calculations but
>>> it affects my results in the case of electron-phonon calculation by using
>>> Wannier functions.
>>> 
>>> I would like to ask you a suggestion about how I should proceed to
>>> communicate the corrections I have done to fix it.
>>> 
>>> thank you for your help,
>>> Best regards
>>> 
>>> 
>>> 
>>> 
>>> Giuliana Barbarino
>>> Laboratoire des Solides Irradies
>>> Ecole Polytechnique
>>> Route de Saclay
>>> 91128 Palaiseau
>>> Phone: +33 1 69 33 45 15
>>> 
>> 
>> 
>> 
>> --
>> Paolo Giannozzi, Dip. Scienze Matematiche Informatiche e Fisiche,
>> Univ. Udine, via delle Scienze 208, 33100 Udine, Italy
>> Phone +39-0432-558216, fax +39-0432-558222
> 
> 
> 
> -- 
> Paolo Giannozzi, Dip. Scienze Matematiche Informatiche e Fisiche,
> Univ. Udine, via delle Scienze 208, 33100 Udine, Italy
> Phone +39-0432-558216, fax +39-0432-558222

Nathalie VAST
Senior researcher
Member of the Editorial Board of Physical Review B 

Laboratoire des Solides Irradies
Ecole Polytechnique
F-91128 Palaiseau
Phone: +33 1 69 33 45 51
https://portail.polytechnique.edu/lsi/en/research/materials-science-theory







-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.quantum-espresso.org/pipermail/developers/attachments/20170410/808c3959/attachment.html>