[Wien] lapw2 aborted during SCF using 3rd structure in force minimization

[Laurence Marks]

You have misunderstood the UG. Wien2k knows about fixed positions due
to symmetry and so long as you have entered your positions with
precision, e.g. 0.33333333 not 0.33330000 you should not impose
additional constraints yourself. In addition there is no reason to use
NEW1 if you do have constraints as both PORT and MSR1a obey them.
However, unless you have a very good reason I do not recommend using
constraints.

As to why your calculation crashed, no idea as you have not provided
enough information for anyone to guess. I suspect that you have chosen
inappropriate parameters and/or have a mistake in your input. Most
oxides are centrosymmetric and a common mistake is to get a lower
symmetry by not entering the initial positions with enough accuracy.

On Thu, Aug 23, 2012 at 5:39 AM, shamik chakrabarti <shamikphy at gmail.com> wrote:
> Dear wien2k users,
>
>      I was running force minimization of a 56 atomic cell ( an oxide
> material) by constraining the coordinates of elements other than oxygen as
> that is the only variable parameter (other coordinates are fixed obeying
> space group symmetry) in wien2k 11.1
>
> I was using NEW1 minimization method following user guide -- "In case of
> constraint calculations one should use NEW1"
>
> Two structure files having different atomic coordinates were already
> created.
>
> while when running SCF calculation using the 3rd struct file, SCF was
> aborted by mentioning the line at the 4th iteration:
>
>  >   lapw2 -c -up     (15:01:51) Abort
> 3.348u 0.320s 0:01.61 227.3% 0+0k 0+20376io 0pf+0w
> error: command   /home/shamik81/WIEN2k/lapw2c uplapw2.def   failed
>
>>   stop error
>
> Another unusual thing is that the energy and charge convergence in different
> iterations of this SCF cycle went on as below:
>
> EC: .000041       CC:  .0007728
> EC:  .00600493   CC. .0028021
> EC:  .002993535 CC. .0028017
>
> There was no error file created and I haven't found any error indicated in
> case.output2 (up/dn) file and case.scf2up file was empty as lapw2 got
> aborted when it was just started.
>
> Charge distance in the above SCF cycle went on as following:
>
> :DIS  :  CHARGE DISTANCE       ( 0.0007728 for atom   48 spin 2)
> 0.0002381
> :DIS  :  CHARGE DISTANCE       ( 0.0028021 for atom   29 spin 2)
> 0.0019903
> :DIS  :  CHARGE DISTANCE       ( 0.0028017 for atom   29 spin 2)
> 0.0019911
>
> We are not able to figure out what the problem is. Any response in this
> regard will be very helpful for us.
>
> with regards,
>
> --
> Shamik Chakrabarti
> Senior Research Fellow
> Dept. of Physics & Meteorology
> Material Processing & Solid State Ionics Lab
> IIT Kharagpur
> Kharagpur 721302
> INDIA



-- 
Professor Laurence Marks
Department of Materials Science and Engineering
Northwestern University
www.numis.northwestern.edu 1-847-491-3996
"Research is to see what everybody else has seen, and to think what
nobody else has thought"
Albert Szent-Gyorgi