[Pw_forum] pwcond error: NAN value of transmission

[zhout2]

Paolo,

Thank you very much for your reply!
Could you tell me which routine is involved, and is there a quick fix?

Best wishes,
Tianji


On 2018-02-09 08:12, Paolo Giannozzi wrote:
> On Fri, Jan 26, 2018 at 4:27 PM, Paolo Giannozzi
> <p.giannozzi at gmail.com> wrote:
> 
>> There are compiler options that catch invalid operations (e.g. -fpe0
>> for Intel compiler)
> 
> well, no, -fpe-all=0. There is actually a division by zero. Thank you
> for reporting this
> 
> Paolo
> 
>  
> 
>> Paolo
>> 
>> On Fri, Jan 26, 2018 at 6:09 AM, zhout2 <zhout2 at rpi.edu> wrote:
>> 
>>> Dear QE community,
>>> 
>>> I was using pwcond.x to do conductance calculations for metals,
>>> which were successful in many systems, but failed in a few others,
>>> in which cases the calculated transmission coefficients are -NAN,
>>> as below:
>>> 
>>> to transmit
>>>  Band j to band i transmissions and reflections:
>>>     j         i     |T_ij|^2    |R_ij|^2
>>> 
>>>     1 -->     1        -NAN        -NAN
>>>     1 -->     2        -NAN        -NAN
>>>     ...
>>>     1 -->     7        -NAN        -NAN
>>>    Total T_j, R_j =       -NAN     -NAN
>>> 
>>> As the calculations were not interrupted and no error message was
>>> given, I am struggling to find the cause of error. Could someone
>>> offer some insight?
>>> 
>>> I have tried qe 5.1, 5.4 and 6.1, yet this error always appeared.
>>> The crystal structure I used should be correct, because for some
>>> other elements the calculations were successful. I'm attaching
>>> both scf and pwcond files, though there was nothing wrong I could
>>> notice with the scf step.
>>> 
>>> Thanks and best regards,
>>> 
>>> Tianji
>>> 
>>> Tianji Zhou
>>> Department of Materials Science and Engineering
>>> Rensselaer Polytechnic Institute
>>> 
>>> _______________________________________________
>>> Pw_forum mailing list
>>> Pw_forum at pwscf.org
>>> http://pwscf.org/mailman/listinfo/pw_forum [1]
>> 
>> --
>> 
>> Paolo Giannozzi, Dip. Scienze Matematiche Informatiche e Fisiche,
>> Univ. Udine, via delle Scienze 208, 33100 Udine, Italy
>> Phone +39-0432-558216 [2], fax +39-0432-558222 [3]
> 
> --
> 
> 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
> 
> 
> 
> Links:
> ------
> [1] http://pwscf.org/mailman/listinfo/pw_forum
> [2] tel:+39%200432%20558216
> [3] tel:+39%200432%20558222
> 
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