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["徐" <lanqingxu@fjnu.edu.cn>]

Dear matthieu,
Sorry for the late response.I revised my input file and found that the 
problem came from a wrong parameter nwchan in the anaddb input file. I reset 
it bigger and now it can pass the anaddb code.Sorry for this silly mistake!
But the phonon spectrum seems to be a little odd. I plot it from two 
different pathes:1)L-gamma-X-K-gamma;2)gamma-K-X-gamma-L-X-W-L. The latter is 
OK but the former has a "mistake" at the next gamma point. Could it be 
natural or not?The eps files are also attached.
I got warnings from abinis like following,
 cgwf3: WARNING -
  New trial energy at line       4 =  -1.248589E+03
     is higher than former: -1.248589E+03
afterscfloop: WARNING -
   ELF is not yet implemented for non collinear spin cases.
What do these warnings meaning? how can I avoid them?
Thank you for any suggestion.
Best regards,
sincerely
shelleny

>From: matthieu verstraete <matthieu.jean.verstraete@gmail.com>
>Reply-To: forum@abinit.org
>To: 徐<lanqingxu@fjnu.edu.cn>
>Subject: Re: [abinit-forum] thermodynamical function tolerance problem
>Date:Mon, 10 Aug 2009 13:40:13 +0200
>
>Hello anaddb users
>
>This happens quite often: the thermodynamic functions, and usually
>just the phonon DOS, is compared for successive refinements of the
>interpolating phonon q-grid. As soon as the difference in DOS (maximum
>diff at all frequencies) is below the tolerance it stops refining.
>
>1) you may need a finer grid, but I doubt it
>
>2) you should look at the DOS at different grid densities to see what
>is changing.
>
>3) the most common cause is negative modes, which are accumulated in
>the first bin of the DOS. This means that as the grid is refined this
>element of the DOS changes strongly (and does not really converge -
>worse the remaining weight in the rest of the modes also fluctuates,
>if some negative mode q-points are neglected).
>
>                             If you have negative modes, the
>convergence _will not work_
>
>This is normal, as the modes are unphysical. Plotting the band
>structure is still fine, but in the worst cases the negative modes are
>off the high-symmetry lines and do not appear in normal BS plots.
>There will be a spike in the phonon DOS accumulated in thm9, however.
>We should put a test in the thermodynamical part to avoid these
>deadlocks...
>
>Matthieu
>
>
>
>2009/8/8 徐
:
>> Dear forum users,
>>   I've successfully calculated thermodynamical properties with the 
>> following
>> input file. Later I changed the input parameter for RF calculation and
>> overwrote the merged DDB. But when I change the revised parameters to the
>> original ones and get a newly merged DDB, analyze it with  the following
>> input file, it  always end in error.
>> Error message:
>>  thm9 : ERROR -
>>   No thermodynamical function is printed out :
>>   the tolerance level that was asked
>>   has not been match with the grids specified.
>>   Action : in the input file, increase the resolution
>>   of grids ng2qpt, or decrease the accuracy requirement thmtol.
>>
>>  leave_new : decision taken to exit ...
>> I tried ng2qpt   20 20 20  & ng2qpt   30 30 30,thmtol  0.30   & thmtol
>> 0.003 , it is always the same.
>> Does that because of parameters in anaddb input file, or because of 
>> privious
>> RF calculation?The input file for anaddb is as following, and the input 
>> file
>> for RF calculation is in the attachment.
>> Any suggestions will be appreciated.
>> Thanks,
>> Best regards,
>> shelleny

Attachment: pbtephonon.eps
Description: PostScript document

Attachment: pbtephonon2.eps
Description: PostScript document