[Wien] LAPW2: semicore band-ranges too large

Luis Ogando lcodacal at gmail.com
Wed Sep 27 20:18:07 CEST 2017


Dear Prof. Blaha,

   Thank you very much for your help !
   Do not worry ! I removed only the l=0 lo orbitals for C. The   "   0
-0.70      0.002 CONT 1   " lines were preserved.
   Yes, I used RKmax=3.0 , but it was reduced to  RKM= 2.37  due to
NMATMAX. Do you believe that this can be related to the "effective" RKmax
value ? I can increase NMATMAX, recompile LAPW1 and try again, but I would
like your opinion before starting such a time consuming calculation.
   During optimization, when Gamma was the only k-point, I tested the basis
size through an SCF cycle (MSR1) with an intermediary structure *and
iqtlsave = 1.* In that case, the effective RKmax was 2.38 and the
calculation converged without a problem, but the RMT's were smaller than
now (0.98 (C), 1.18 (N) and 0.64 (H)).
   Is there any other parameter that you would like to know ?
   Thank you again.
   All the best,
                     Luis

2017-09-27 1:49 GMT-03:00 Peter Blaha <pblaha at theochem.tuwien.ac.at>:

> As I said, iqtlsave should ONLY be used in very special cases (high
> pressure). It usually is a hint for ghostbands and one should not switch it
> of.
>
> I don't think the problems come from a not optimized structure, except
> when the positions would be extremely wrong.
>
> The RMTs are probably ok.
>
> When I say, you should remove the lo for C, l=0, I meant to remove the
> line with l=0 and 0.30 as energy parameter, but keep the line with -0.7xx.
>
> PS: I hope you reduced RKMax to 3 (or for the beginning to save time
> during crude position optimization even 2.75)
>
> Am 26.09.2017 um 19:31 schrieb Luis Ogando:
>
>> Dear Prof. Blaha,
>>
>>     Thank you very much for your response !
>>     The molecule has 100 atoms and the only symmetry operation is
>> identity. You can imagine the computation time required for optimization. I
>> turned "iqtlsave" off during optimization in order to avoid interruption
>> due to fortuitous atom displacement. Anyway, after getting the relaxed
>> structure, I turned it on again (and got the problem).
>>     The RMT's I am using are 1.25 (C), 1.24 (N) and 0.67 (H). These
>> values were suggested by init_lapw.
>>     As you previewed, l=0 local orbitals for C are problematic and I
>> removed them during optimization. I also removed the l=0 local orbitals for
>> N and kept the same basis set for the next calculations, with the optimized
>> structure.
>>     I believe that it is important to say that I got the error message on
>> the SCF cycle number 25 after energy convergence on cycle 23 (-ec 0.0001
>> -cc 0.0001). During optimization I used  "-ec 0.001 -cc 0.001 -fc 1.0"  .
>> Do you believe that the problem can be related to a "non" fully relaxed
>> structure ?
>>     Thank you again !
>>     All the best,
>>                  Luis
>>
>>
>> 2017-09-25 16:57 GMT-03:00 Peter Blaha <pblaha at theochem.tuwien.ac.at
>> <mailto:pblaha at theochem.tuwien.ac.at>>:
>>
>>     Yes, worry !!
>>
>>     Why did you change iqtlsave in the first place ? It is not sace and
>>     ment only for special cases like very large pressure.
>>
>>     I guess you had spurious ghost bands and most likely the problems
>>     come form the small C sphere and the l=0 LO on Carbon.
>>     Remove the C l=0 local orbital.
>>
>>
>>     Am 25.09.2017 um 20:56 schrieb Luis Ogando:
>>
>>         Dear Wien2k community,
>>
>>              My system is a molecule (H, C and N) with vacuum along "y"
>>         and "z".
>>              After optimizing the structure using only the Gamma point
>>         (large cell) and iqtlsave = 0, I am trying to get the DOS using
>>         more k-points.
>>              To do this, I turned iqtlsave on (iqtlsave=1) and I am
>>         getting the message "LAPW2: semicore band-ranges too large".
>>         Should I worry about this ?
>>              Thank you very much.
>>              All the best,
>>                               Luis
>>
>>
>>
>>
>>         _______________________________________________
>>         Wien mailing list
>>         Wien at zeus.theochem.tuwien.ac.at
>>         <mailto:Wien at zeus.theochem.tuwien.ac.at>
>>         http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien
>>         <http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien>
>>         SEARCH the MAILING-LIST at:
>>         http://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/
>> index.html
>>         <http://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at
>> /index.html>
>>
>>
>>     --     -----------------------------------------------------------
>> ---------------
>>     Peter BLAHA, Inst.f. Materials Chemistry, TU Vienna, A-1060 Vienna
>>     Phone: +43-1-58801-165300 <tel:%2B43-1-58801-165300>
>>  FAX: +43-1-58801-165982 <tel:%2B43-1-58801-165982>
>>     Email: blaha at theochem.tuwien.ac.at
>>     <mailto:blaha at theochem.tuwien.ac.at>    WIEN2k: http://www.wien2k.at
>>     WWW:
>>     http://www.imc.tuwien.ac.at/tc_blaha------------------------
>> -------------------------------------------------
>>     <http://www.imc.tuwien.ac.at/tc_blaha-----------------------
>> -------------------------------------------------->
>>
>>
>>
>>
> --
> --------------------------------------------------------------------------
> Peter BLAHA, Inst.f. Materials Chemistry, TU Vienna, A-1060 Vienna
> Phone: +43-1-58801-165300             FAX: +43-1-58801-165982
> Email: blaha at theochem.tuwien.ac.at    WIEN2k: http://www.wien2k.at
> WWW: http://www.imc.tuwien.ac.at/tc_blaha------------------------
> -------------------------------------------------
> _______________________________________________
> Wien mailing list
> Wien at zeus.theochem.tuwien.ac.at
> http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien
> SEARCH the MAILING-LIST at:  http://www.mail-archive.com/wi
> en at zeus.theochem.tuwien.ac.at/index.html
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://zeus.theochem.tuwien.ac.at/pipermail/wien/attachments/20170927/62ba934f/attachment.html>


More information about the Wien mailing list