[Pw_forum] Help me to solve a problem in Charge Density Difference calculation using Quantum Espresso

[Bibhas Manna]

Dear Stefano Sir,

Thank you once again.

I will try to recompute the same following your suggestions.

Thanking you.
Bibhas

On Sat, Aug 12, 2017 at 8:38 PM, stefano de gironcoli <degironc at sissa.it>
wrote:

> you take the final vc-relaxed cell and assume the same for the two
> separate fragments.
> And you need to redo the scf calculation (only the scf calculation) of the
> combined system so as to have the same parameters for all three.
>
> stefano
>
>
>
>
> On 12/08/2017 17:04, Bibhas Manna wrote:
>
> Dear Matthieu,
>
> Since, I have done the geometry relaxation using *vc-relax,* how can I
> maintain the same *Cell_Parameters* for all the three cases.
>
> Thanks.
> Bibhas
>
>
> On Sat, Aug 12, 2017 at 8:22 PM, Matthieu Fortin-Deschênes <
> matthieu.fortin-deschenes at polymtl.ca> wrote:
>
>> I'm no expert, but I think you need to make the scf calculations with
>> the same parameters, especially ecutrho and CELL_PARAMETERS.
>>
>> Matthieu
>>
>> Bibhas Manna <mannabibhas at gmail.com> a écrit :
>>
>> > Dear Sir,
>> >
>> > Thanking you for your quick reply.
>> >
>> > I have used the same parameter for three charges. Following are the
>> input
>> > pp.x files:
>> >
>> >
>> > *For Substrate + molecules:*&inputpp
>> >     prefix  = 'PG_4_HCHO_PBE'
>> >     outdir = './tmp/'
>> >     filplot = 'PG_4_HCHO_charge'
>> >     plot_num= 0
>> >  /
>> >  &plot
>> >     nfile = 1
>> >     filepp(1) = 'PG_4_HCHO_charge'
>> >     weight(1) = 1.0
>> >     iflag = 2
>> >     output_format = 3
>> >     fileout = 'PG4_HCHO.rho.dat'
>> >     e1(1) =1.0, e1(2)=0, e1(3) = 0.0,
>> >     e2(1) =0.0, e2(2)=0.0, e2(3) = 1.0,
>> >     nx=56, ny=40
>> >  /
>> >
>> > *For Substrate only:*&inputpp
>> >     prefix  = 'PG_4_PBE'
>> >     outdir = './tmp/'
>> >     filplot = 'PG_4_charge'
>> >     plot_num= 0
>> >  /
>> >  &plot
>> >     nfile = 1
>> >     filepp(1) = 'PG_4_charge'
>> >     weight(1) = 1.0
>> >     iflag = 2
>> >     output_format = 3
>> >     fileout = 'PG4.rho.dat'
>> >     e1(1) =1.0, e1(2)=0.0, e1(3) = 0.0,
>> >     e2(1) =0.0, e2(2)=0.0, e2(3) = 1.0,
>> >     nx=56, ny=40,
>> >  /
>> >
>> >
>> > *For Gas molecule only:*&inputpp
>> >     prefix  = 'HCHO_PBE'
>> >     outdir = './tmp/'
>> >     filplot = 'HCHO_charge'
>> >     plot_num= 0
>> >  /
>> >  &plot
>> >     nfile = 1
>> >     filepp(1) = 'HCHO_charge'
>> >     weight(1) = 1.0
>> >     iflag = 2
>> >     output_format = 3
>> >     fileout = 'HCHO.rho.dat'
>> >     e1(1) =1.0, e1(2)=0.0, e1(3) = 0.0,
>> >     e2(1) =0.0, e2(2)=0.0, e2(3) = 1.0,
>> >      nx=56, ny=40,
>> > /
>> >  I am actually getting  error in the reading of the filepp(2) as
>> follows:
>> >
>> > Reading header from file  PG_4_HCHO_charge
>> >
>> >    Info: using nr1, nr2, nr3 values from input
>> >      Reading data from file  PG_4_HCHO_charge
>> >      Reading data from file  PG_4_charge
>> >
>> >
>> > %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
>> %%%%%%%%%%%%%%%%%%
>> >      Error in routine chdens (1):
>> >      incompatible gcutm or dual or ecut
>> >
>> > %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
>> %%%%%%%%%%%%%%%%%%
>> >
>> >      stopping ...
>> >
>> > Thanks.
>> > Bibhas
>> >
>> > On Sat, Aug 12, 2017 at 7:59 PM, stefano de gironcoli <
>> degironc at sissa.it>
>> > wrote:
>> >
>> >> you need to compute the three charges with the same parameters
>> >>
>> >> stefano
>> >>
>> >>
>> >> On 12/08/2017 16:20, Bibhas Manna wrote:
>> >>
>> >> Dear All,
>> >>
>> >> I am very new to Quantum Espresso. I want to get a charge density
>> >> difference plot for a gas molecule adsorbed on the single layer
>> graphene
>> >> surface. Presently I am using pp.x to compute the same in QE v.5.1
>> >> following an equation:
>> >>
>> >>     ∆ρ=ρAB – ρA-ρB
>> >>
>> >> Where, ρAB, ρA and ρB are the charge densities of graphene -molecule
>> >> complex, graphene and molecule respectively. I have successfully
>> computed
>> >> all of these three charge densities using pp.x. Now, I am trying to
>> find
>> >> out the charge density difference using pp.x with nfile = 3, while all
>> of
>> >> these three charge files are available to me as inputs.
>> >>
>> >> Unfortunately, I got an error in the output log:
>> >> *Error in routine chdens (1):
>> >>        incompatible gcutm or dual or ecut*
>> >>
>> >> Since, I have different number of atoms in each of the three files, how
>> >> can I make the charge files having same number of atomic coordinates?
>> >>
>> >> I am sharing my input and output files for your kind considerations.
>> >>
>> >> Can you help me to solve this problem?
>> >>
>> >> Thanks with regards,
>> >> Bibhas Manna
>> >> Research Scholar,
>> >> IIT Kharagpur, India
>> >>
>> >>
>> >>
>> >> _______________________________________________
>> >> Pw_forum mailing
>> >> listPw_forum at pwscf.orghttp://pwscf.org/mailman/listinfo/pw_forum
>> >>
>> >>
>> >>
>> >> _______________________________________________
>> >> Pw_forum mailing list
>> >> Pw_forum at pwscf.org
>> >> http://pwscf.org/mailman/listinfo/pw_forum
>> >>
>>
>>
>>
>> _______________________________________________
>> Pw_forum mailing list
>> Pw_forum at pwscf.org
>> http://pwscf.org/mailman/listinfo/pw_forum
>>
>
>
>
> _______________________________________________
> Pw_forum mailing listPw_forum at pwscf.orghttp://pwscf.org/mailman/listinfo/pw_forum
>
>
>
> _______________________________________________
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://pwscf.org/mailman/listinfo/pw_forum
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.quantum-espresso.org/pipermail/users/attachments/20170812/db78968e/attachment.html>