[Pw_forum] hybrid functional error

[hannu.komsa at epfl.ch]

Since n is always 1, and by quickly looking at the code it should be  
that x>=0. Furthermore, x should be zero only if the density gradient  
is zero and the screening parameter is set to zero (=screening length  
infinity = PBE0). If you have done so, then you can fix the problem by  
either using PBE0 or using a very small parameter value (btw., these  
two approaches give slightly different results, although they should  
give the same). If you haven't done so, then... ?


Hannu-Pekka Komsa
University of Helsinki

>
>> from expint : error #         1
>> bad arguments
>>
>> Where is the problem?
>
> it is where the error message says it is: in "expint" (flib/expint.f90).
> If you go inside the file, you will see that this error arises when
>    * n < 0 , or
>    * n=0,1 and x<=0, or
>    * n>1 and x<0
> The second case is the relevant one, I guess,
> Please specify which version of QE you are using: there have been
> several minor changes to the HSE routines since the first release.
>