[Pw_forum] Plotting phonon dispersion

elchatz at auth.gr elchatz at auth.gr
Mon Feb 19 14:29:27 CET 2018


Thank you Vahid Askarpour.

I have two questions:

a) Is there a problem if I don't specify amass?

b) I have already done this procedure using the following files:

ph.x:

&inputph
   prefix   = 'Si',
   epsil    = .false.,
   fildyn   = 'diam.dyn',
   ldisp    = .true.
   fildvscf = 'dvscf'
   nq1=6,
   nq2=6,
   nq3=1,
   tr2_ph   =  1.0d-12,
   recover = .true.
  /

This run ok

q2r.in:

  &input
   fildyn='diam.dyn',
   flfrc='Si.rc'
  /

This run ok

matdyn.in:

  &input
     flfrc='Si.rc',
     flfrq='Si.freq',
     q_in_band_form=.true.
  /
  4
  gG 50
   X 50
   M 50
   gG 8

And I got the following error:

   
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
      Error in routine find_bz_type (1):
      Wrong ibrav
   
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

Is it possible that this is because I messed up the names of the  
files, or do I need to include explicitly the coordinates of the high  
symmetry points?


Regards

Eleni




Quoting Vahid Askarpour <vh261281 at dal.ca>:

> Once you get all the .dyn files from the ph.x run, use the following  
> input to q2r.x to get the force constants:
>
>  &input
>    fildyn=’Si.dyn', zasr='simple', flfrc=’Si.ifc2’
> /
>
> Then use the following input to matdyn.x:
>
> &input
>     asr='simple',  amass(1)= 28.0855
>     flfrc=’Si.ifc2', flfrq=’Si.freq', q_in_band_form=.true.
> /
> 6  ! number of high-symmetry points
> 0.0 0.0 0.0 200
> 0.0 0.0 1.0 200
> etc.
>
> The coordinates of the high symmetry points should be in cartesian  
> coordinates. 200 points will be calculated for each segment. The  
> phonon dispersion is in the .gp output file.
>
> Cheers,
>
> Vahid
>
> Vahid Askarpour
> Department of Physics and Atmospheric Science
> Dalhousie University,
> Halifax, NS, Canada
>
>> On Feb 19, 2018, at 4:54 AM, elchatz at auth.gr wrote:
>>
>> Hello all,
>>
>> I am using ph.x to get the phonon frequencies and dynamical matrices
>> for an epw.x calculation, however, I would like to plot my phonon
>> dispersions from the ph.x calculation for far, as for example is shown
>> in
>>
>> http://epw.org.uk/Documentation/B-dopedDiamond
>>
>> I am lost as to how I can do that. My ph.x file is as follows,
>>
>> &inputph
>>   prefix   = 'Si',
>>   epsil    = .false.,
>>   fildyn   = 'diam.dyn',
>>   ldisp    = .true.
>>   fildvscf = 'dvscf'
>>   nq1=6,
>>   nq2=6,
>>   nq3=1,
>>   tr2_ph   =  1.0d-12,
>>   recover = .true.
>>  /
>>
>> Do I need to use q2r.x and matdyn.x to the files for plotting?
>>
>>
>> Thank you
>>
>>
>>
>> --
>> Dr. Eleni Chatzikyriakou
>> Computational Physics lab
>> Aristotle University of Thessaloniki
>> elchatz at auth.gr - tel:+30 2310 998109
>>
>> _______________________________________________
>> 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



-- 
Dr. Eleni Chatzikyriakou
Computational Physics lab
Aristotle University of Thessaloniki
elchatz at auth.gr - tel:+30 2310 998109




More information about the users mailing list