[Pw_forum] matdyn.x warning message (Mikiyas Tsegaye)

Mikiyas Tsegaye mastermik at gmail.com
Fri Aug 21 21:40:02 CEST 2009


Dear Eyvaz,

My q-path is the following: (from matdyn.in input file)
-----------------------------------
&input
asr='simple',
amass(1)= 12.01,
flfrc='graphene.fc',
flfrq='graphene.freq',
/
14
0.0 0.0 0.0   0.0
0.0 0.1 0.0   0.0
0.0 0.2 0.0   0.0
0.0 0.3 0.0   0.0
0.0 0.4 0.0   0.0
0.0 0.5 0.0   0.0
0.1 0.1 0.0   0.0
0.2 0.2 0.0   0.0
0.3 0.3 0.0   0.0
0.33 0.33 0.0 0.0
0.3 0.3 0.0   0.0
0.2 0.2 0.0   0.0
0.1 0.1 0.0   0.0
0.0 0.0 0.0   0.0

------------------------------------

How do you want me to send you my force constant file? It is quite  
large (6 X 6 X 1 grid). Is it OK to email such large number of lines  
to the public forum. Or perhaps a private email?

thank you for your help.

> Dear Friends,
>
> I'm trying to plot the phonon dispersion of graphene. I have done the
> dispersions for Silicon, and Germanium, and also for Diamond. All of
> which worked out well. Graphene, however, is giving me the following
> error in the second-to-last matdyn.x step:
>
> --------------------------------------------------------------------
> message from routine matdyn
>
> Z* not found in file graphene.fc, TO-LO splitting at q=0 will be  
> absent
> A direction for q was not specified: TO-LO splitting will be absent
>
> --------------------------------------------------------------------
>
> The dispersion that it then produces looks very jagged and the numbers
> are off. For examples, the acoustic modes don't go to zero at the
> gamma point, and the acoustic and optical branches don't touch at the
> K-point like they're supposed to. I would really appreciate any help
> on this matter. My input file is as follows:
>
> -----------------------------------------------
> # SCF step
>
>  &control
>     calculation='scf',
>     restart_mode='from_scratch',
>     prefix='graph',
>     tstress=.true.,
>     tprnfor=.true.,
>     pseudo_dir = '$PSEUDO_DIR/',
>     outdir='$TMP_DIR/'
>  /
>  &system
>     ibrav = 0, nat=2, ntyp= 1,
>     ecutwfc = 40.0,
>     ecutrho = 480.0,
>     occupations = 'smearing',
>     smearing = 'gaussian',
>     degauss = 0.02,
>  /
>  &electrons
>     diagonalization = 'cg',
>     conv_thr =  1.0d-6
>  /
> CELL_PARAMETERS {hexagonal}
> 4.02  2.321  0.00
> 4.02 -2.321  0.00
> 0.00  0.00   69.75
> ATOMIC_SPECIES
> C 12.01 C.pz-vbc.UPF
> ATOMIC_POSITIONS {bohr}
> C  0.0  0.0  0.0
> C  2.68 0.0  0.0
> K_POINTS automatic
> 16 16 1 0 0 0
>
> $PW_COMMAND < graphene.scf.in > graphene.scf.out
>
> # calculate phonons
>
> phonons of graphene
> &INPUTPH
>  amass(1) = 12.01,
>  outdir = '$TMP_DIR/',
>  prefix = 'graph',
>  tr2_ph = 1.0d-12,
>  fildyn = 'graph.dyn',
>  fildrho = 'graph.rho',
>  ldisp = .true.,
>  lnscf = .true.,
>  nq1 = 16,
>  nq2 = 16,
>  nq3 = 1
>  -------------------------------------------------------
>
> Am I missing something in my inputs?
>
> thank you!
>
> - Mikiyas Tsegaye
> University of Virginia, ECE
> Charlottesville, VA, USA
> mst3c at virginia.edu
>
>
> ------------------------------
>
> Message: 3
> Date: Thu, 20 Aug 2009 13:49:31 -0700 (PDT)
> From: Eyvaz Isaev <eyvaz_isaev at yahoo.com>
> Subject: Re: [Pw_forum] matdyn.x warning message
> To: PWSCF Forum <pw_forum at pwscf.org>
> Message-ID: <707183.40234.qm at web65704.mail.ac4.yahoo.com>
> Content-Type: text/plain; charset=iso-8859-1
>
> Dear Mikiyas,
>
>> Z* not found in file graphene.fc, TO-LO splitting at q=0
>> will be absent
>> A direction for q was not specified: TO-LO splitting will
>> be absent
>
> The first message is just stating that you consider graphene as a  
> metallic system for which there is no LO-TO splitting, of course.
>
> The second message: may be your q-path does not contain Gamma point.  
> Anyway, it is harmless in your (metallic) case
>
> If you send me your fc-file and  q-path,  I will try to have a look  
> at.
>
>> ? ???ecutrho = 480.0,
> You do not need such high ecutrho as you use norm-conserving PsP.
> Use default value (4*ecutwfc).
>
> By the way, did you specify zasr in q2r.in and matdyin.in files?
>
> Bests,
> Eyvaz.
>
> -------------------------------------------------------------------
> Prof. Eyvaz Isaev,
> Theoretical Physics Department, Moscow State Institute of Steel &  
> Alloys, Russia,
> Department of Physics, Chemistry, and Biology (IFM), Linkoping  
> University, Sweden
> Condensed Matter Theory Group, Uppsala University, Sweden
> Eyvaz.Isaev at fysik.uu.se, isaev at ifm.liu.se, eyvaz_isaev at yahoo.com
>
>
> --- On Thu, 8/20/09, Mikiyas Tsegaye <mastermik at gmail.com> wrote:
>
>
>>
>> I'm trying to plot the phonon dispersion of graphene. I
>> have done the?
>> dispersions for Silicon, and Germanium, and also for
>> Diamond. All of?
>> which worked out well. Graphene, however, is giving me the
>> following?
>> error in the second-to-last matdyn.x step:
>>
>> --------------------------------------------------------------------
>> message from routine matdyn
>>
>> Z* not found in file graphene.fc, TO-LO splitting at q=0
>> will be absent
>> A direction for q was not specified: TO-LO splitting will
>> be absent
>>
>> --------------------------------------------------------------------
>>
>> The dispersion that it then produces looks very jagged and
>> the numbers?
>> are off. For examples, the acoustic modes don't go to zero
>> at the?
>> gamma point, and the acoustic and optical branches don't
>> touch at the?
>> K-point like they're supposed to. I would really appreciate
>> any help?
>> on this matter. My input file is as follows:
>>
>> -----------------------------------------------
>> # SCF step
>>
>> ? &control
>> ? ???calculation='scf',
>> ? ???restart_mode='from_scratch',
>> ? ???prefix='graph',
>> ? ???tstress=.true.,
>> ? ???tprnfor=.true.,
>> ? ???pseudo_dir = '$PSEUDO_DIR/',
>> ? ???outdir='$TMP_DIR/'
>> ? /
>> ? &system
>> ? ???ibrav = 0, nat=2, ntyp= 1,
>> ? ???ecutwfc = 40.0,
>> ? ???ecutrho = 480.0,
>> ? ???occupations = 'smearing',
>> ? ???smearing = 'gaussian',
>> ? ???degauss = 0.02,
>> ? /
>> ? &electrons
>> ? ???diagonalization = 'cg',
>> ? ???conv_thr =? 1.0d-6
>> ? /
>> CELL_PARAMETERS {hexagonal}
>> 4.02? 2.321? 0.00
>> 4.02 -2.321? 0.00
>> 0.00? 0.00???69.75
>> ATOMIC_SPECIES
>> C 12.01 C.pz-vbc.UPF
>> ATOMIC_POSITIONS {bohr}
>> C? 0.0? 0.0? 0.0
>> C? 2.68 0.0? 0.0
>> K_POINTS automatic
>> 16 16 1 0 0 0
>>
>> $PW_COMMAND < graphene.scf.in > graphene.scf.out
>>
>> # calculate phonons
>>
>> phonons of graphene
>> &INPUTPH
>> ? amass(1) = 12.01,
>> ? outdir = '$TMP_DIR/',
>> ? prefix = 'graph',
>> ? tr2_ph = 1.0d-12,
>> ? fildyn = 'graph.dyn',
>> ? fildrho = 'graph.rho',
>> ? ldisp = .true.,
>> ? lnscf = .true.,
>> ? nq1 = 16,
>> ? nq2 = 16,
>> ? nq3 = 1
>> ?
>> -------------------------------------------------------
>>
>> Am I missing something in my inputs?
>>
>> thank you!
>>
>> - Mikiyas Tsegaye
>> University of Virginia, ECE
>> Charlottesville, VA, USA
>> mst3c at virginia.edu
>> _______________________________________________
>> Pw_forum mailing list
>> Pw_forum at pwscf.org
>> http://www.democritos.it/mailman/listinfo/pw_forum
>>
>
>
>
>
>
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>
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